Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: quickmagic on April 23, 2024, 01:37:12 am
Title: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: quickmagic on April 23, 2024, 01:37:12 am
Hi, I'm a new guy.
I tried to look this up in past forums, but was not having any luck.
I recently purchased a 1984 diesel front engine unit. I need to know a couple of things:
First, where can I find manuals of all types on this unit?
Also, from reading past forums, there appears to be some problems getting a replacement alternator for this unit. I have the old one which I will have rebuilt and keep as a spare, but I would like to buy a new 160 amp alternator, and would like to know what kind to buy, and what needs to be done to install it. There must be something available in the under $200. price that will work, with or without modifications.
Thank you so much for your help, I do appreciate it.
Moderator Jeff edited title to help get your qustions answered.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on April 23, 2024, 08:55:03 am
Welcome New Guy! We always like to see new faces around here.
The more info you can give us, the more we can help you. Where are you located? if you can post photos it would help us answer your questions. Do you have a link to the classified ad where you found your coach? Photos of your coach will help us know exactly what year and model we are dealing with. If you find a metal plate containing the VIN number/MODEL number somewhere inside the coach post a photo of that.
As for the alternator question, a few photos of your old alternator would be helpful, especially the back side showing the wiring posts. We have to know exactly how your old alternator was connected before we can recommend a replacement.
If you did not get any owner manuals with your acquisition, then you will have to do some digging. You can use the Forum SEARCH function (top right corner of page) to look for archived posts pertaining to your model coach. You may also find some info in the pages linked below:
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: John44 on April 23, 2024, 09:21:24 am
Get us the above mentioned info and we can help.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: nitehawk on April 23, 2024, 09:53:15 am
James Holder has a 1984 GV and is located in TN at a RV dealership as their service manager. If anyone could help it would be James. Hardest part is getting a hold of him.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on April 23, 2024, 01:42:33 pm
Thank you for your reply, where would I lok for a vin plate?
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Gerry Vicha on April 23, 2024, 02:04:32 pm
Usually to the left of the driver's seat under the window. may be different on your coach.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: craneman on April 23, 2024, 06:19:41 pm
On my '81 it is on the inside of the cupboard door on the left as you enter the coach.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: red tractor on April 23, 2024, 08:08:09 pm
Does your coach have the 8.2 v8 Detroit Diesel engine? It should have a battery isolator somewhere between the alternator and the batteries. I believe your batteries are under the step as you enter the coach.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on April 26, 2024, 10:31:46 am
I found the info you are looking for, however photos not working on computer, I'll give you the info and hopefully you can get what you need from that to help me: VIN; IRF120231201000223 Model: R-800
But what I really need is to know which alternator fits : The tag on it reads: Lestek Inc. 14 volts, Amps, 105HD Model, 91 35M ser.# 27452
The unit has 3 connection points, all on the back, from left to right, they are: Threaded post, Male plug in 2 pin, 1st labeled R, second labeled F, ; last is a threaded male post labeled GRD.
Hopefully this is enough info to identify which alternator I can use.
Thank you for your help, it is much appreciated.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on April 26, 2024, 11:51:39 am
Hopefully this is enough info to identify which alternator I can use.
We're getting closer to an answer to your alternator question. We need more info. As red tractor said, you may (or may not) have a battery isolator somewhere on your coach. Look at the photo below, and then look around to see if you find anything similar. It will be a large aluminum device with cooling fins and 3 or 4 large posts with battery cables attached. Tell us what you find (or don't find).
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on April 26, 2024, 05:46:42 pm
Does the back of your alternator look like the photo below? Yes, I know the photo shows a Delco 10DN alternator, but Lestek Inc often sold reconstructed units from other manufacturers. IF your alternator looks like the 10DN, then it is a externally regulated unit which requires a external voltage regulator. It is not designed to be used with a diode based battery isolator, which is why we need to know if your coach has a battery isolator. If you do have a battery isolator, then you may wish to upgrade to a modern internally regulated DUVAC alternator that is designed to work with the isolator.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: red tractor on April 26, 2024, 07:38:21 pm
I am pretty sure that you have an isolator. The post marked ground does go to ground. The other large post should be the positive post Th wires in the plug, I am not sure which is the sense wire and the other is the excite wire which would have voltage on it with the ignition switch turned on. Some of those years of coaches would not start charging until the engine was around a 1000 rpm. Once they started charging then they would keep charging even at an idle. That is how both of our 84 coaches worked. One had a 3208 Cat and the other one has the 8.2 Detroit. Where are you located? I am in Florida and my 84 with the Detroit could be bought. It's a rear engine Oskosh chassis. I have worked on the front engine 8.2 and there is no extra room around it.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on April 27, 2024, 01:20:20 am
Without the ground wire, wouldn't that indicate that it doesn't have an external regulator?
Both wires on the plug in have juice running to them with switch on.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on April 27, 2024, 09:06:04 am
It would help move this conversation along if you could just answer the questions.
1. Did you find a battery isolator on your coach?
2. Does the rear of your old alternator look like the photo I posted earlier?
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: John Wolfe on April 27, 2024, 04:50:44 pm
To answer your question about manuals. I didn't receive any manual when I bought my used FT U320. My first call was to FT in Texas. They were able to supply me with a complete User Manual and several other manual. What they were unable to supply,I found by Google using Modle and serial number.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on April 27, 2024, 05:25:52 pm
Thank you to everyone who responded, I really appreciate it, and you are saving me tons of time. I did fined what i am pretty sure is a stand alone voltage regulator, however, there is no isolater anywhere, I have been crawling under cars motorcycles, boats, and every other kindof motor vehicle you can imagine, so its doubtful that I overlooked the isolater. So, what is my solution for an alternater for my unit, no worries if somethi9ng goes wrong, I wont blame anythingon anyonelse, especially when this saves my hours and hours of research. Thank you!
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on April 27, 2024, 05:33:26 pm
Oh, I forgot to ask, there is no obvious plug into the coach for shore power, the manual that I do have doesnt hVE BUT 2 or 3 pioctures in it, but I just spot the shore power plug into the coach.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on April 27, 2024, 06:47:48 pm
1. I did find what i am pretty sure is a stand alone voltage regulator 2. There is no isolator anywhere 3. What is my solution for an alternator for my unit
1. You still have not answered the question about your old alternator (does it look like the photo I posted). If you are not sure what a mechanical voltage regulator looks like, see the image below. If you DO have a externally regulated alternator, then it would definitely be a good idea to upgrade to a modern internally regulated model. Mechanical regulators are really ancient tech, and will not contribute to long service life for your batteries.
2. If your coach doesn't have a battery isolator, then you need to decide if you want one or not. The answer to question #3 depends on your answer. You have to think about how you want to set up the charging circuit for your batteries. The original factory system on most Foretravel coaches did include a isolator. The purpose of the isolator is to allow both battery banks to be charged simultaneously from the the same charging source, and ALSO to keep the battery banks separated when they are being discharged. However, there are other ways to accomplish the same objective, such as using a DVSR (Digital Voltage Sensing Relay), or you could use a simple manual battery combining switch to control when and how your batteries charge and discharge.
3. Once you decide the answer to #2 above, then we will know what type alternator to recommend.
4. Another question: How many batteries does your coach have, and what type (flooded acid, AGM or GEL)?
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on April 28, 2024, 04:19:18 am
Sorry, I did send an answer, don't know what happened to it. The alternator looks Identical.
I don't want to use a battery hand operated switch, That is what my voltage regulator looks like.
A dvsr will probably be my choice, but I know nothing about them, are they external, are they hard to install, what would you choose?
Batteries, right now I have 2, but with all cables going to the first battery, I don't think that is currently wired so an isolator would work, the second battery is attached to the first with a cable going to each post, nothing more. The batteries are the standard wet batteries.
For the time being, I would like to install an alternator without doing a bunch of modifying, don't have time for that now, but will do that in the future when i have more time.
Again, thank you for your help.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on April 28, 2024, 09:00:07 am
OK, so right now you have the old alternator, which is a externally regulated model with a separate mechanical voltage regulator. You have two standard flooded batteries. It sounds like they are connected in parallel (positive to positive, negative to negative). With this battery setup, both batteries are being charged simultaneously by the alternator (or other charging source), AND both batteries are used both to start the coach engine and to power the 12 volt devices in the coach.
There is nothing wrong with having your batteries set up like this. It is above all simple and easy to understand. With this arrangement you can use almost any off-the-shelf 12 volt alternator. There is no need for a DVSR or a battery isolator. The disadvantage of this setup is that you must keep a close eye on your battery voltage. If you are dry camping (not plugged in to a power outlet) there is a chance that you might run your batteries down to the point that you could not start your engine. A good digital voltmeter, mounted in the coach so you can constantly monitor the batteries, is a recommended component.
If you wish to stay with your present (simple) battery setup, then like I said any standard internally regulated alternator will work. You will need to match the mounting bolt location and spacing of the old alternator, and the drive pulley will have to match. Your best bet is to take your old alternator to a good rebuilding shop or parts store (like NAPA) and let them suggest a suitable replacement model. Let them know you want a 160A 1-wire internally regulated model that will fit on the existing mounting brackets and accept the original pulley.
Your new alternator will only require one wire - that will be the battery charging cable from the alternator B+ output post to the positive post on one of the batteries. See the diagram below. Note that the alternator connects to the POS post on one battery, while the connection to GROUND comes off the other battery. This is the preferred wiring method with two (or more) batteries in parallel. More alternator conversion info below:
Why Convert to A One Wire Alternator (https://www.speedwaymotors.com/the-toolbox/why-convert-to-a-one-wire-alternator/28748#:~:text=The%20self%2Dsensing%20voltage%20regulator,the%20regulator%20and%20begin%20charging).
In the future, if you wish to add a DVSR to separate your batteries, you will still be able to use the same alternator. You can research that subject on your own. Example of a DVSR linked below:
Digital Voltage Sensing Relay (DVSR) 12/24V (https://www.bepmarine.com/en/p/710-140A/Digital-Voltage-Sensing-Relay-DVSR)
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on April 28, 2024, 04:10:40 pm
What do i do with the existing regulator wiring?
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on April 28, 2024, 04:49:02 pm
looks like nthe alternater is a GM CS130 type, is that correct?
I cannot advise on what alternator would work for your application, since I am not there to look at it. I have never even seen a 1984 front engine diesel Foretravel. I have no idea how the alternator is mounted. You will have to make this determination.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on April 28, 2024, 06:00:15 pm
Do I need to ask for anything specific, other than what you mentioned when buying this alternator? Do you think 160 amps is overkill?
The alternator is mounted right up on top , easy access, its just like any GM, two mounting castings, with holes running front to rear, with front mount being about 2-3 inches long, that is the bottom hold in place mount, the second is on the pulley end of the unit, and is used as the tightening bolt. The pulley is a v-belt type with cooling fins.
So, what I need is a 160 amp 12 volt GM type alternator with an internal voltage regulator, and set up as a one wire? Is there any more?
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on April 28, 2024, 07:03:48 pm
Do you think 160 amps is overkill? So, what i need is a 160 amp 12 volt GM type alternator with an internal voltage regulator, and set up as a one wire? Is there any more?
Yes, that's all you need. It just has to match up with the existing mounting bolt holes, and position the drive pulley in proper alignment with the other pulleys, so the V-belt runs straight and true.
160 amp is not "overkill'. It may not be necessary with your present battery setup, but will provide some headroom if you later wish to add more storage (batteries).
Doesn't hurt anything to oversize an alternator (other than increasing the purchase price).
Our '93 U280 came with a 130A alternator (which was not factory original). I replaced it with a 200A Delco 28SI. Completely different engine and mounting situation than yours, but you might be interested in my installation.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: red tractor on April 28, 2024, 07:30:09 pm
For the question about shore power there should be a receptacle on the left side of the vehicle. It might be silver metal or maybe white plastic. Lift up and you should see where to plug in the power cord. It should have a 50 amp cord.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on April 29, 2024, 09:39:14 am
OK, check this out to make sure that I am doing this correctly. I am going to buy a GM type alternater ( for correct mounting holes), A 16ne0 12 volt with an internal regulater. To attach, mount just as old alternater, do not use the exterior voltage regulator, Buy an alternater with an internal voltage, mount it as usual, attach the cable from the positive from batteries, to alternater , and tjhen connect the negative cable to the negative post on alternater to ground. Hereis the part where I'm not sure, first, do I plug the twin wire plug into alternater, or not, and can I just leave the old regular wiring in place, and can I just wrap up and tape the wiring? So that the way i understand it, is that correct? Thank you for all your help!!
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on April 29, 2024, 10:04:29 am
1. Buy an alternater with an internal voltage, mount it as usual 2. attach the cable from the positive from batteries, to alternater 3. and tjhen connect the negative cable to the negative post on alternater to ground. 4. Hereis the part where I'm not sure, first, do I plug the twin wire plug into alternater 5. can I just leave the old regular wiring in place, and can I just wrap up and tape the wiring?
1. Yes 2. Yes 3. Yes 4. No. The "twin wire plug" wiring harness is connected on the other end to the old voltage regulator, which is no longer required. 5. Yes
When you have decided what alternator you will purchase, if possible post a link to the description before you pull the trigger. Even if you are buying it at a local store, you should be able to find it for sale somewhere online, along with a listing of the technical specs and installation instructions.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: John44 on April 29, 2024, 10:52:28 am
Fill out the signature form and tell us where you are,someone may be near you to help or may know of a shop near you,will help with the process.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on May 11, 2024, 09:56:23 pm
update, there is a battery isolater on the coach, I found it hiding way underneath. I did get and install CW 130 ALTERNATER, IT BOLTED UP JUST FINE, I wires it as follows, blur wire that wasn originally wired to the previous alternator, and was 12V ignition on, ignition off, 0 V. , That is conected to F terminal; the s conection post, i routed to the alternater + battery post on the rear of alternater. Volt meter shows 11.5 V at the battery, and zero V at the alternater. So what in the hell could thaT BE, Battery disconnected during installation, so no shorts or sparks. The alternater is a brand new cs 160 style from Southwest Perfarmance parts in Phoenix. All I can figure is that I got a bad alternater. Any thoughts on this?
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Caflashbob on May 11, 2024, 10:46:16 pm
More alternator amps may not charge your exact capacity battery banks any faster. Batteries can only accept a certain amount of input power. STD charging rates from most makers currently state eith 5C or 20C. C being the batteries capacity in amp hours.
So either 5% or 20%.
Thats why Foretravel used the 105? Amp alternator. More amps would not charge any faster normally. 105 would charge 2 8D's.
So a 250 amp hour 8D max charge rate should be 50 amps until it reaches the bulk charge voltage then a smart charger will taper down the charging amps to avoid over charging the battery.
The 81 FTX chargers were battery boilers. I killed a lot of batteries back then. A modern charging system will greatly increase your batteries life. I was a Foretravel stores sales manager in the 80's and have driven and rved in similar coaches.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on May 11, 2024, 11:24:02 pm
All I can figure is that I got a bad alternater. Any thoughts on this?
It is more likely that you are connecting the new alternator improperly, but unless you can post a photo of the alternator wiring terminals, along with a copy of the installation instructions, there is no way to help you.
We need more information.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: red tractor on May 12, 2024, 08:25:28 pm
With the battery isolator, you need a duvac alternator in order for it to charge properly. There are many posts here on duvac alternator and how to wire them up and troubleshoot them.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on May 14, 2024, 07:01:36 am
OK, I'll shoot a pic of the alternater and see if ican send it. Any picture that I take wont be sharp enough to see the lettering. There is a 4 prongplug on the side, top of alt, those letters from the top down are P L F S, other than thatthere is positive post on the side and a ground in back. I'll follow with a pic if I can get it to work. Butmi will keep you informed. Thank you for your help,it is much appreciated.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on May 14, 2024, 09:30:55 am
1. there is a battery isolater on the coach, I found it hiding way underneath.
2. I did get and install CW 130 ALTERNATER, IT BOLTED UP JUST FINE
3. I wires it as follows: A. blur wire that wasn originally wired to the previous alternator, and was 12V ignition on, ignition off, 0 V. , That is conected to F terminal; B. the s conection post, i routed to the alternater + battery post on the rear of alternater.
4. Volt meter shows...zero V at the alternater.
5. So what in the hell could thaT BE...
6. All I can figure is that I got a bad alternater.
7. Any thoughts on this?
1. So you DO have an isolator. Now we need to know if the isolator is being used, or is it bypassed? Follow the B+ charging cable from the alternator - where does it go? Does it connect to the isolator center post, or directly to one of the batteries?
2. I take it you mean "CS" 130 alternator.
3. Wiring connections IF your alternator is similar to the diagram below: A. The blue "Hot with Ignition ON" excite wire should not be connected to the F terminal. Try connecting it to the L terminal - see what happens. It may need a resistor to function properly. B. The alternator S terminal is the "SENSE" terminal. IF your alternator output cable is connected directly to one of the battery positive posts, then the way you have the SENSE wire connected (to the alternator B+ output post) will work OK (although it is not ideal). IF your alternator output cable goes to the center post on the isolator, then you do not have the SENSE wire connected properly. With the isolator in the circuit, the SENSE wire must be connected DIRECTLY to the positive post on the start battery, OR to the START battery post on the isolator.
4. This is probably because the alternator is not "turning on".
5. It could be due to improper wiring.
6. Not too likely.
7. Yes - see above comments.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on May 20, 2024, 02:40:26 pm
Chuck, The isolater hAS 3 POSTS, HOWEVER i CANT READ IT. tHE alternater goes to the moddle post, there is a heavy cable coming off the front post and back up front to the engine area, a wire comming off the 3rd post going to tnhe batteries, and a second wire attached to the middle post going towards the back of the coach. So, I will run a seperate wire from alternater directly to the batteries, What gauge wire should that be? Thank you for your help.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on May 20, 2024, 04:58:09 pm
1. The isolater hAS 3 POSTS 2. tHE alternater goes to the moddle post 3. there is a heavy cable coming off the front post and back up front to the engine area 4. a wire comming off the 3rd post going to tnhe batteries 5. and a second wire attached to the middle post going towards the back of the coach 6. I will run a seperate wire from alternater directly to the batteries, What gauge wire should that be?
1. This is probably a common 3 post diode based isolator.
2. Middle post is generally correct for the alternator cable, although some isolators do not follow this convention. The other posts should be connected to your batteries - one post to your engine start battery, and the other post to your coach battery. It doesn't matter which post goes to which battery.
3. So the cable running from the "front" isolator post goes where? You need to follow that cable and see where it terminates.
4. "a wire coming off the 3rd post goes to the batteries". Is this a lighter gauge wire or a heavy gauge cable? It sounds like this is the wire charging both of your batteries. If that is the case, then it needs to be a fairly heavy cable...not a light gauge wire.
5. "a second wire attached to the middle (alternator) post going towards the back of the coach" I have no idea what would be the purpose of this wire. You need to trace this wire and find out where it goes.
6. "I will run a separate wire..." You need to run this wire from the alternator "S" terminal to the POS (+) post on the engine start battery. This wire will not carry any significant current - it is just a SENSE wire that measures battery voltage. Any general purpose 14 or 16 gauge wire will be fine.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on May 21, 2024, 03:06:05 am
Thank you very much, It has been pouring rain the last few days, andI didn't trace tjhe rear bound small gauge wire, or the engine ound heavy gauge wire going bsck towards the engine because the grass nwas wet and Imjust wanted to get off the grass as quick as I could. I'll let you know when I find that stuff out.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on May 22, 2024, 02:32:57 pm
Chuck, I was looking at an article on how to install alternator on this application. I dont know if this is applicsble or not, but that article said when disconnecting regulartor to attach then far right wire to the far ledft wire, and njustr cap off the mioddle two leads on the wireas at trhe alternastor. Is this correct? You said in your wiring instrucrtions to use the blue wire as the excite wire,. and to run that to the L terminal at the alternator. The blue wire yiou are talking about, ismthat tjhe blue wire that was originally on the two wire connection to the alternator? If so, athend I detrach all wires from the regulator, will that still be usable as the excite wire? Im ready to go on tjhis, and those are the only concerns that remain. Thank you! Bill
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on May 22, 2024, 02:48:41 pm
Bill,
I can't follow all the wires you are talking about, and I don't know what article you were reading. Go back and read Reply #35 again. I described how a CS130 alternator should be connected. You will need to figure out what wires to use, where the wires come from, and where they should go. The voltage regulator and associated wires are no longer required with the new alternator. You may or may not be able to reuse the voltage regulator wires. Without being there to see the stuff in person, there's only so much I can do to help you. Sorry, but providing long distance remote assistance with unfamiliar electrical systems is very difficult.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on May 22, 2024, 04:53:12 pm
True, Am I correct in assuming that the current regulator should be disconnected?
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on May 22, 2024, 04:58:46 pm
Am I correct in assuming that the current regulator should be disconnected?
Yes, assuming that the new alternator has an internal regulator. Does it?
Did the new alternator come with wiring instructions? If so, that would be your best guide as to how it should be wired.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on May 22, 2024, 06:27:44 pm
The alternator is internally regulated, it did not come with instructions. T traced the wire running aft from the isolator, IT runs back to whatn i believve is an air pump mounted above the rear axel, it also has a good sized wire running nto batteries. i began to follow the hose, it goes into the engine compartment next to the front left side. I'll track iot the rest of trhe way later. what strikes me as odd is the fact that there are no heavy battery cables comming from the iasolater to the batteries, all heavy leads going to the batteries look to me like they are comming from up[ front, and just go to batteries directly. I'll look at that closer.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on May 23, 2024, 06:10:36 am
I dont think that the isolater is connected.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: wolfe10 on May 23, 2024, 07:48:19 am
You really need to find someone familiar with the alternator/isolator on your coach.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on May 23, 2024, 09:14:25 am
Bill,
I agree with Brett (above). It sounds to me like the wiring on your coach is a mess. It is hard for you to describe to us what you are seeing, because you don't know what the correct wiring should look like. It is hard for us to tell you how to correct what you are seeing because we aren't there to see it in person. You need to find someone who understands exactly how your coach should be wired, and can then make the corrections, or else start over from scratch and do it right.
In Reply #35 I told you how a CS130 alternator should be connected, with or without an isolator. You (or someone) must decide which setup is most appropriate, and then connect the alternator according to the instructions.
Your coach, with one alternator and two batteries, should have a very simple charging system. It can be made to work just fine with or without a battery isolator. The line diagram below shows how the components on your coach would be connected if you wish to use a battery isolator. If you don't want to use an isolator, then you just run the charging cable directly from the B+ post on the alternator to the B+ post on the start battery.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on May 25, 2024, 09:11:46 pm
Hi Chuck, Duvac alternator came in today, I'm gonna take some pics of it before I install it, and see if I can fifgure out how to get them on here for your wviewing pleasure. And if you would be willing to share some advice on how this should be wired, I would appreciate it. If there is a nything other than what we have already duiscussed, or if you wa nt clairification, please let me know what you need to give me your best shot at it. This czme with directions too, I'll t include them as well. Thank you very much for your help, most people or youube videos dont have a lot on installation for RV app,lications.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Chuck & Jeannie on May 25, 2024, 09:34:58 pm
DUVAC alternator is pretty simple - should have either three or four places to connect wires.
1. Alternator B+ output: battery cable goes to the alternator post on the isolator, OR (if no isolator) then direct to B+ post on engine START battery.
2. Alternator SENSE terminal: wire is connected to either the START battery post on the isolator, or direct to the B+ post on START battery. The SENSE wire is HOT all the time.
3. Alternator EXCITE terminal: wire is connected to a voltage source that is HOT only when ignition switch is turned to ON position.
4. Alternator NEG post (if it has one): cable connects to a good clean (bright metal) grounding point on the engine block or the frame.
That's all there is to it. Page linked below has a diagram of a basic two battery DUVAC alternator hookup:
https://www.dixie-electric.com//tsb/TSB_704.pdf
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on June 06, 2024, 05:58:05 am
THANK YOU!
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on June 09, 2024, 10:58:25 am
Here's whereI am at right now. I got the Duvac alternator and installed it. I had to do some modifying because I bought aa 160 amp model. When I got this, this whole system was connected together as one electrical system. In other words, there were not two seperate batteries, one for starting, and one for coach. Before I get 'too far, it looks to me like this was a Duvac system, originally, but for some reason, the owner apparently decided that it would be better to have it all combined, so at this point I don't understand how it is wired. I have 4 batteries all connected to each other + to + and - to -. At tjhis point I would just like to get it running, and figure out the entire system in the future. My question is, if I hook up all wires as they currently are, making sure that the correct wires go to the intended spot, can I run it that way without isolating the 2 battery system, just to run it until i get a chance to figure out how those wired should go without damaging anyhing? I intend to wire itr correctly as we move forward, I just dont want to take the time right now to trsce all of the wires. Thank you for your help
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: wolfe10 on June 09, 2024, 11:18:06 am
My question is, if I hook up all wires as they currently are, making sure that the correct wires go to the intended spot, can I run it that way without isolating the 2 battery system, just to run it until i get a chance to figure out how those wired should go without damaging anything?
Can't comment on how it is wired-- sounds like a lot of "creative wiring" by previous owner(s).
But, addressing your specific question: Having one large battery bank (house and chassis banks combined) presents no problems other than both banks will discharge together, so no "the house bank is dead, but still have chassis bank to be able to start the engine".
And, depending on where the two banks are combined, you may be able to separate them while parked if so desired.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: quickmagic on June 09, 2024, 01:22:31 pm
Thank you very much for your answer. I don't think that the wiring is goofed up, It pretty much looks like it came out of the factory this way with a couple of small w[ires that have been added or a replacement.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: Protech Racing on June 09, 2024, 04:19:47 pm
The batts are easy to combine. Could be at the boost solenoid Simply stacked cables. Could be that you had 2 start batts , one under the steps next to a single house battery. Simply add a connector cable between the systems.
Title: Re: 1984 FORETRAVEL - New owner with questions
Post by: wolfe10 on June 09, 2024, 04:21:58 pm
The batts are easy to combine. Could be at the boost solenoid Simply stacked cables.
Yes, battery boost/combine solenoid OR the diode-based battery isolator are both easy places to "combine" battery banks by stacking cables.
Title: SPLIT: Re: 1984 FORETRAVEL - Vent fan question
Post by: Michelle on June 09, 2024, 04:32:46 pm
One or more of the messages of this topic, the ones related to the vent fan, have been moved to Foretravel Tech Talk (https://www.foreforums.com/index.php?board=5.0) - https://www.foreforums.com/index.php?topic=48051.0 (https://www.foreforums.com/index.php?topic=48051.0)
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: quickmagic on June 09, 2024, 08:29:42 pm
OK, Alternator installed, wired and its running. Here's the result, 13.3 amps at the alternator, and 12.5 at the batteries. I think that is normal?
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: craneman on June 09, 2024, 08:38:45 pm
You need 14+ volts at the battery
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: wolfe10 on June 10, 2024, 09:02:23 am
OK, Alternator installed, wired and its running. Here's the result, 13.3 amps at the alternator, and 12.5 at the batteries. I think that is normal?
And, the voltage drop between alternator and batteries suggests a problem that needs to be addresses first. Could be as simple as a poor or loose connection on either positive or negative side.
This ASSUMES you are not running B+ through a diode-based battery isolator, but as you mentioned previously that you are "combining all batteries". That means B+ from alternator and the cables to each battery bank on ONE lug. If so, voltage drop between alternator and batteries should be near zero.
If you are still going through a diode-based isolator, that suggests the SENSE wire is not connected to the chassis battery as it should be (or another place with large-gauge cable to chassis battery such as chassis battery lug on the isolator). Easy enough to run a temporary wire from chassis battery connection to alternator sense terminal to test.
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: Protech Racing on June 10, 2024, 09:24:19 am
I bypassed the isolator to reduce charging and draw issues. Just stack the batt cables all on the same stud . You don't need the isolator . This will charge everything to about the same voltage . It will also draw all of the batteries down . My meters show about 13.4 for the leece Neville and 13.8 for the ac delco. When I have them separated. I combine with the boost switch . You need to figure out what cables go to what batteries first. And. Design from there . Imho
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: quickmagic on June 14, 2024, 05:38:54 pm
The issue with lower voltage at the battery than the alternator I have had before in another vehicle. Other forums said to look for corrosion at basttery cable ends and if found, take them all apart and clean the cable ends, however one person said he had just added an extra cable from alternator to battery, I tried it, it worked, much easier than taking cables apart and cleaning ends. On the current coach, it looks like the cable from the alternator to the isolater has been replaced, and it appears to be light, measured 3/8" diameter. Is that too light? Could that be the problem, also has some corrosion at cable ends. I think I can just add another cable, it would be helpfull to know what gauge that cable should be, from alternator to isolater. And if I want to wire this correctly, alternaator goes to middle post, one of the other posts handles the engine, etc, and the other post handles the coach. So io just have to figure out what each wire is for. Correct? does ti matter whether I hook up coach to either front or back post as lond as other cables all go to engine etc.?
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: red tractor on June 14, 2024, 08:34:17 pm
I would think 2 gauge wire would be good from alternator to the center post. All engine battery wires to one end post and all of house battery cables to the other end post. It doesn't make any difference which end is which.
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: prfleming on June 15, 2024, 08:48:26 am
OK, Alternator installed, wired and its running. Here's the result, 13.3 amps at the alternator, and 12.5 at the batteries. I think that is normal?
The 0.8 voltage drop is not due to wire loss, it is the normal voltage drop from the diode isolator. Adding additional wire won't hurt, but it won't raise the voltage at the alternator.
Did you get the "sense" wire hooked up? This is necessary with an isolator to boost the alternator voltage to cover the diode voltage drop and should give you better voltage at the battery.
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: wolfe10 on June 15, 2024, 11:25:04 am
The 0.8 voltage drop is not due to wire loss, it is the normal voltage drop from the diode isolator. Adding additional wire won't hurt, but it won't raise the voltage at the alternator.
Did you get the "sense" wire hooked up? This is necessary with an isolator to boost the alternator voltage to cover the diode voltage drop and should give you better voltage at the battery.
Yes, as I mentioned in post #58 it depends on whether alternator B+ is still wired through the diode-based battery isolator (in which case the voltage drop IS normal) or if B+ and at least chassis battery are wired to the same lug.
And, if wired through a diode-based battery isolator, the sense wire is NOT on the chassis battery side of the isolator as it needs to be.
In post #50, OP said: "Before I get 'too far, it looks to me like this was a Duvac system, originally, but for some reason, the owner apparently decided that it would be better to have it all combined..."
AND in the same post "if I hook up all wires as they currently are, making sure that the correct wires go to the intended spot, can I run it that way without isolating the 2 battery system, just to run it until i get a chance to figure out how those wired should go without damaging anyhing? I intend to wire itr correctly as we move forward, I just dont want to take the time right now to trsce all of the wires."
Something is still wrong, but we need to know how it was wired during the test!
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: quickmagic on June 21, 2024, 12:31:10 pm
OK, got the alternator wired up, belt is tight, all connections are tight, the wire from the alternator goes to the center post of the isolater, but the wire seems to be lighter than a normal battery cable. The alternator reads 13.4 to 14 volts, but it reads 12.5 at the battery. i am going to get a heavier cable to replaced current one from isolater to alternator, but until i figure out the wiring to wire it as the two systems, I want to take the new heavier wire and run it from the alternator to the batteries, and leave the wire from the alternator to the isolater as it is. My question is, if i do that, will it cause any problems or hurt anything? Thank you for your help with this, electronics is not my strong suit and i really do appreciate you sharing your knowledge with me on this. it saves me a ton of time doing the research.
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: wolfe10 on June 21, 2024, 12:49:57 pm
NO, if you have a diode-based battery isolator in place you can't both wire to it (center lug) AND directly to the battery.
The sense wire/function would be totally confused. The battery bank wired through the isolator would be undercharged/the battery bank wired directly would be the only one to get proper voltage. And if your sense wire happened to be on the "other"/house battery instead of the chassis battery and you wire directly to the chassis battery from the alternator, you would way overcharge the chassis battery.
Before considering replacing the wire from the alternator B+ to center lug of the diode-based battery isolator, Test from each to good ground and see if the voltage drop is from the alternator to isolator (in which case, you do need to address it) OR if the voltage drop is in the isolator. Remember, there will be around .7 VDC drop from B+ lug of the isolator to the two battery/outer lugs.
Voltage readings you posted with engine above idle of 13.4-14 is low with a diode-based isolator AND way too wide a range. Again, please post readings from good clean ground to: alternator B+, center lug of isolator and each of the outer lugs of the battery isolator (which are directly connected to the battery banks) and lastly voltage readings at each battery bank with the engine at around 1,100 RPM.
Said another way, I strongly suggest you diagnose and fix the problem, don't totally re-engineer a system that has been tired and true for decades.
Can you wire around the diode-based battery isolator-- sure, but you would need to do it correctly so you don't either over or undercharge one of the battery banks.
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: dsd on June 21, 2024, 12:54:02 pm
OK, got the alternator wired up, belt is tight, all connections are tight, the wire from the alternator goes to the center post of the isolater, but the wire seems to be lighter than a normal battery cable. The alternator reads 13.4 to 14 volts, but it reads 12.5 at the battery. i am going to get a heavier cable to replaced current one from isolater to alternator, but until i figure out the wiring to wire it as the two systems, I want to take the new heavier wire and run it from the alternator to the batteries, and leave the wire from the alternator to the isolater as it is. My question is, if i do that, will it cause any problems or hurt anything? Thank you for your help with this, electronics is not my strong suit and i really do appreciate you sharing your knowledge with me on this. it saves me a ton of time doing the research.
take your volt meter and measure from the alternator to the Isolator. If the wire is too small you will read voltage. Corrosion will also show up as indicated voltage. .2 volts lost here and there ends up being too much pretty quick. Quick and easy to check. If you read no voltage that's perfect , but everything has a resistance and will show some loss. I would retain the original intent
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: Dennis H on June 21, 2024, 04:56:09 pm
After some warming up the voltage drop across the isolator will be over a volt, closer to 1.2 volts. The sense wire for the alternator needs to go to the chassis battery for a number of reasons. The most important is that it is the priority for not only charging the battery but ensuring adequate voltage and current is available for the chassis systems. From the practical view, the chassis batteries will normally be at a higher state of charge. As the house batteries may be at a lower state of charge and often of much higher capacities, and often with vary loads connected while driving/charging, this design will allow the house batteries to be at a lower voltage, rising as the state of charge increases eventually catching up to the chassis batteries. The current limiting effect during the bulk charge stage is actually better for the batteries and helps to reduce total load on the alternator somewhat. Foretravel is different using this diode approach. Most use some form of relay control, based on ignition on or alternator charging, or an automatic voltage-controlled relay, (my preference). A downside of the diode approach is another means is required to use a shore/generator powered charger to charge the chassis batteries. That is why Foretravel uses the maintained boost switch so the chassis batteries can be charged by the house battery charger. Hope this makes sense.
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: quickmagic on August 27, 2024, 06:54:55 am
UPDATE; Here is where the entire project has evolved to; Got the big alternator installed, had to modify the adjustment bracket, no big deal, reem out the adjusting Slot with a grinder or whatever works best, add about a 2" extension to base of bracket. So mount up is great. Then the question was how to wire it. Found 3 different wiring diagrams, followed all of that best I could, it charges great, havnt run it on the road yet to see how it works. The issue I am dealing with now, is, when running vehicle on an outside generator, batteries seen to run dead prematurely, I am running 4 regular batteries, each individually charged each one, checked voltage, load tested them and replaced any questionable one, but doesn't seem to get enough juice stored in batteries to turn motor over, hook a jumper vehicle up to it, fires right up. When I wired this, some diagrams showed a hot lead comming from the onboard battery going to the coach battery. There was no such wire in my unit, 1. Do I need to add that wire to the entire scheme to make this work? 2. Is it possible that the onboard battery charger isn't operating correctly, it is original, would anyone care to make a recommendation on installing a new one, and which one that would be. Thank you all once again. As this unit comes together, with your gracious help, it becomes more and more comfortable every day. Thank you all very much for your help. I appreciate it.
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: Dennis H on August 27, 2024, 08:40:31 am
Trying to help as much as possible but difficult with modified systems. For most of the Foretravel that use the battery isolator, Duvac system, the generator gets its power from the house batteries, and the either a power converter charger or inverter charger charges those. There is not auto connect for the generator/house power to charge the chassis batteries. To do this the "boost" relay gets closed and that ties both banks together.
If the chassis batteries are really drained down or weak for some other reason turning on the boost will not be able to transfer enough power to start the main engine, you need to allow some time. Confirm that battery voltage is rising, give an hour or so. Since you are doing this level of work you should have adequate metering tools including a clamp on DC ammeter. You can only diagnose so much using voltage measurements only. Learn Ohm's and Kirchhoff's laws, especially voltage drops with current flow and most everything DC will make sense.
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: wolfe10 on August 27, 2024, 09:54:54 am
For us to assist you, you need to draw out and post exactly how your alternator/battery bank and starter are wired.
Title: Re: 1984 FORETRAVEL - New owner with alternator/isolator/chassis battery questions
Post by: red tractor on August 27, 2024, 08:02:09 pm
Your chassis batteries are not charged from the charger that charges the house batteries. If you have the original battery charger that is I believe to be a magnetron 75 you need to replace it with one of the new chargers that are 3 stage. I don't remember, but pretty sure that the 84 did not have a duvac alternator. When you started the coach it got excite voltage from the wire feeding the shut off fuel solenoid and would not start charging until the engine was reved up to about a 1000 rpm once it started charging it would continue even at idle.