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Topic: Boost switch, not boosting... (Read 1771 times) previous topic - next topic

Re: Boost switch, not boosting...

Reply #25

I have a couple pictures downloaded to my PC and would like to show them on this thread. Someone shared how to do this before someplace but I cannot find it. I have done a few more tests but would like to post pics with comments.

Carl Sandel
1991 36' U280
Northern Michigan

Re: Boost switch, not boosting...

Reply #26
I have a couple pictures downloaded to my PC and would like to show them on this thread. Someone shared how to do this before someplace but I cannot find it. I have done a few more tests but would like to post pics with comments.


Look in the "Help Forum"
How to Add Images to your Posts
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: Boost switch, not boosting...

Reply #27
Ahh! Thanks Barry...now I've got it :)
The pic of the meter is the one I currently use. I only look smart carrying it around but really have no idea how to use it. Here's what I've been doing to get the readings I've gotten.

Looking at the meter as a clock face, between 9 and 12 where the white print is, I have had it set to that 20 mark. Is this correct for what I've been doing?

The selenoid pic is actually in my battery compartment and I have only the one small post and 2 large.
While the engine was running and the RPM was at 1100 I connected 2 alligator clips with wires ( for safety away from the fan ) so I could connect the wires with my digital meter. I connected red to red and black to black on the back of the alt. Here is what it read.
1100RPM.......1.13
With engine at idle.......1.07
Boost on or off made no difference.

When I went out to the selenoid in the battery compartment, at idle with red on the large post on the left and black touching the small post in the middle, 12.50 and then red on the right post and black still in the middle 12.41.

With the RPM's 1100 and testing both the same way again....everything was the same.

NOW...running 1100RPM's AND hitting the boost switch....left post, .94 and right post .85

So, what gives.......bad selenoid or bad alt...OR BOTH??

Is there a "size" selenoid to buy or how will I know exactly what I need to replace it?

How much would some of you expect to have to pay for a rebuilt alt vs new?

I hope this is making sense and if there is ANYTHING else I need to check that you know I have not or need to recheck...LET ME KNOW and I'll get after it today :)

PS....I did NOT test as Brett mentioned by disconnecting and jumping and listening for a "click". I got a bit confused by the detail and didn't know if I could only do that with a 2 small and 2 big post selenoid or also with the one like I have...so I didn't do it..
Carl Sandel
1991 36' U280
Northern Michigan

Re: Boost switch, not boosting...

Reply #28
Carl,

Northern Michigan and the photos are a pretty good indication that you will probably need some cleanup and replacement on your isolator mounting plate down the road. Perhaps not far down the road. None of the components are expensive but do take some thought before starting to replace them. Before removing anything, I would buy a label machine and make labels for each wire and where it goes. The factory did code the wires/cables but time may have made them hard or impossible to read. If you have a compressor, a small hand held Harbor Freight sandblaster will take the corrosion off after the cables/components have been removed. Sand can make a mess so prep work is required. Wire wheel will also do the job. The previous owner of our U300 changed the isolator but mixed the cables up and gave me a huge headache until I realized what was wrong. A search of our forum will show the solenoid part number and price. Isolator has to be large enough to handle the alternator output. If the alternator needs service, I would use a local auto electric shop rather than a rebuilt exchange unit. They can also help with the isolator mounting plate clean up and sell you a new solenoid(s), isolator and the small relays needed to make it 100%. Naturally, the batteries have to be disconnected before servicing the components. Photos are a good way of remembering where things go.

Local auto electric shop nicks me around $100 for automotive alternators with new bearings, brushes, etc. Larger units are going to be a little more depending on internal/external regulator or any failed components. They come back looking like new, bead blasted, etc.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Boost switch, not boosting...

Reply #29
Carl... you should have measured over 13vdc while the engine was running on both battery banks. You should also have measured over 13vdc on the alternator output wires (the big ones). I strongly suspect that it is *only* the alternator that is not working.

If you have a side radiator it's easy to remove the alternator and have someone put it on a bench tester. There is a "tensioner" pully that you insert a "breaker bar" of appropriate size (I think 3/8") and lift up with some force in order to get the belt off all the things it goes over.

Might be a good time to replace the belt just as insurance.

Take some photos to make sure you understand where that belt goes and don't leave any out when you re-install the alternator.

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

Re: Boost switch, not boosting...

Reply #30
The part that troubles me is the difference in house battery voltage with the generator running and when plugged into shore power as the charger should have the same charge amount as both sources are supplying 120 volts to the charger, and as has been mentioned looks like the altenator is not charging. Also the trikle charger will try to keep both batteries nearly the same voltage
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Boost switch, not boosting...

Reply #31
The part that troubles me is the difference in house battery voltage with the generator running and when plugged into shore power as the charger should have the same charge amount as both sources are supplying 120 volts to the charger, and as has been mentioned looks like the altenator is not charging. Also the trikle charger will try to keep both batteries nearly the same voltage

I hadn't noticed this... good catch. Looks like the generator is running a little fast. Time to get a Kill-A-Watt (under $40 at your Lowe's or Home Depot) and check frequency and output of the generator.

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

Re: Boost switch, not boosting...

Reply #32
Carl,

Before you go overboard in replacing or rebuilding, START by cleaning all the electrical contacts and connections. Batteries to isolator to alternator.  You would be amazed how often poor connections cause mus-diagnosies.

Then, re-run your readings.

Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Boost switch, not boosting...

Reply #33
I appreciate everyone's comments, suggestions and help. I don't know if this makes any difference at all but I'm going to throw it out there. I've been in homes performing my work in the past and have noticed that although everyone has regular electricity, some don't run my things the same. I don't notice any difference in my barn but here's the deal. The electricity to my first barn ( 30x40 ) runs from my home and is about 175 away. It's HUGE wire, but never the less, it's about 175 feet away. THEN....the electricity to the coach barn (22x54 with 10 double HO florescent lights ) runs FROM the 30x40 barn...AND runs my shore power. I wonder if there is a significant drop in power when checked with a digital meter???

Thoughts?

Today I was looking at the connections from different items and thought also that I should clean them because they just looked SO BAD! I'll go that route first then as Brett mentioned....I'll recheck and report back.

Curious, what method would you folks use to clean all the connections? Is there a wonder product or just old school knife, razor and or sand paper?

Carl Sandel
1991 36' U280
Northern Michigan

Re: Boost switch, not boosting...

Reply #34
Carl,

Check voltage with your voltmeter.  It will have less drop with smaller amp draw in the coach. 

If this is a standard 15 amp outlet, the short straight is HOT, long straight is NEUTRAL and round is ground.

So:

Short to long= 108-132 VAC with 120 being BEST.
Short to round= same
long to round= zero
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Boost switch, not boosting...

Reply #35
Carl,

My comments aren't directed toward the alternator working or not, but to your boost solenoid. It appears that your boost solenoid wiring is the same as in my coach. I am attaching a pic of mine in which I have labeled the starting battery cable side (right in pic) and house battery cable (on left). With your engine off and BOOST SWITCH OFF. When you put one electrode of your mulitmeter (set to 20VDC on your meter) on the house cable terminal and the other electrode to ground, you will get a reading, let's say 13.6 (it will vary from coach to coach). Then, move electrode to starting battery cable, other electrode still to ground. Your reading will differ, I think by about 0.5V less,  I think House batteries are higher than starting batteries. Turn boost switch on. If voltage is the same on both sides, taking same measurements, your boost solenoid is working as it should. If voltages haven't changed, boost is kaput. Those 3 pole solenoids are not expensive. Any NAPA store or truck parts store can get you a replacement. Minimum would be 125 amp, continuous duty Cole-Hersee, 3 pole solenoid. It shouldn't cost more than $25-$35. I carry two as backups. Have never had to replace the boost solenoid yet (knock on wood); however, I've replaced the dash ignition solenoid 3 times (last time with a Blue Sea electronic switch).
Don Hay
'92 Grandvilla, U-280
The Hayfever Express
Build #4055
'97 GEO Tracker
Life is like licking honey off a thorn.

Re: Boost switch, not boosting...

Reply #36
Excellent gentlemen, thank you!!

Carl Sandel
1991 36' U280
Northern Michigan

Re: Boost switch, not boosting...

Reply #37
Carl,

That is the biggest reason I installed the instrument panel digital voltmeters. I flip a switch to turn them on and can check boost solenoid, alternator, isolator, house batteries in the morning, etc. All for less than $20 delivered and just a little wiring. Here is a link to the kind I use. $7 bucks and change each delivered. Digital Voltmeter Panel 4.5-30V Red LED Waterproof Panel Meter FOR 12V 24V CAR | You do have to wire a switch to turn both off as they will use a very small amount of juice.

If you did not want to wire into your electrical system, you could just plugin a digital voltmeter into the cigarette lighter. Would not check both house and engine batteries but can check alternator/regulator health. NEW 12V Red LED Display Digital Car Volt Meter Vehicle Battery Voltage Gauge

Attached is a photo for the dash digital voltmeters. Sorry in advance to members that have seen this before.

Here is the latest (I think) 24143 Cole-Hersee 200 amp solenoid. At a little over $44, this is the best price I could find and cheaper than when I bought mine. http://www.allbatterysalesandservice.com/browse.cfm/4,7650.html

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Boost switch, not boosting...

Reply #38
If you did not want to wire into your electrical system, you could just plugin a digital voltmeter into the cigarette lighter. Would not check both house and engine batteries but can check alternator/regulator health.
On our coach, the top 12VDC outlet on the dash is powered from the house circuits, and the bottom 12VDC outlet is powered from the chassis circuits. The voltages should be representative of the house and chassis batteries. The voltages will not be as "true" as values from meters on dedicated wires to the batteries, but they will provide enough information to spot problems.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Boost switch, not boosting...

Reply #39
On our coach, the top 12VDC outlet on the dash is powered from the house circuits, and the bottom 12VDC outlet is powered from the chassis circuits. The voltages should be representative of the house and chassis batteries. The voltages will not be as "true" as values from meters on dedicated wires to the batteries, but they will provide enough information to spot problems.

Great tip!!! Had not thought that one out.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Boost switch, not boosting...

Reply #40
Carl,

I see that my image did not get accepted, apparently because I attached it from an email and not here on the forum, so I am attaching it here.  Hope it helps.
Don Hay
'92 Grandvilla, U-280
The Hayfever Express
Build #4055
'97 GEO Tracker
Life is like licking honey off a thorn.

Re: Boost switch, not boosting...

Reply #41
my mechanic said today that AIS can rebuild my alt for $235-$300...which I think sounds high. He can get me brand new for $307. Still going to clean everything up first.
Carl Sandel
1991 36' U280
Northern Michigan

Re: Boost switch, not boosting...

Reply #42
Carl,

My alternator was rebuilt last week for $75.  New brushes, bearings and complete checkout.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Boost switch, not boosting...

Reply #43
Here in Michigan, we are one of the brokest states out there. And for some reason stupid choices like gouging us for nearly everything we do, buy or need seems to be the plan they think is going to turn it all around and get us back on our feet. Idiots...that's all I can say.
I really woould like to do business local, but if it's going to be like that, does anyone believe there to be a savings for my if I ship to one of your guys and ship back? Or is that going to eat up any value I might hope to see?
Carl Sandel
1991 36' U280
Northern Michigan

Re: Boost switch, not boosting...

Reply #44
Shipping would more than eat up the savings. Rudy got a good deal at $75. If you call around to mom & pop auto electric shops, I bet you can come pretty close to that. Our $100 plus is in California where labor is really high.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Boost switch, not boosting...

Reply #45
Carl,

You might get a quote from a UPS store.  I shipped an A/C compressor and dryer two day air last week for $25.

My zip is 77521.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Boost switch, not boosting...

Reply #46
Going back a few posts to one Carl did that showed the rust etc on his isolator and electrical parts, took me back to when I had a look at my panel in front of engine on wall under bed. It too was bad with the road dirt etc getting on it and what I did was simple but now it stays like new (almost).
After removing/replacing and cleaning what was needed I sprayed Corrosion X on the area then fastened a piece of heavy-ish plastic along the top face of wood along the length of elec' panel and draped it down to completely cover the panel with all the solenoids / isolator etc on then hold it back away for heat sources with a piece of curtain nylon covered spring wire with a hook in each end. I put a screww with a large head on either side of panel and stretch the wire to hold the cover against the elec' panel. Now there is no dirt getting to all those fuses etc and all is well. In the last 2 yrs there has been no problem with fire risks or? and no road dirt. Simple, cheap and effective.
John H
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Boost switch, not boosting...

Reply #47
When I replaced the isolator and the boost & starter solenoids I started using dielectric grease on the connections and Corrosion X on the adjacent areas.  I have no more rusting and pitting connections in an area that most would admit is an engineering malpractice to have placed such electrical items (right behind the rear tires on the driver's side).
Peter
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: Boost switch, not boosting...

Reply #48
Going back a few posts to one Carl did that showed the rust etc on his isolator and electrical parts, took me back to when I had a look at my panel in front of engine on wall under bed. It too was bad with the road dirt etc getting on it and what I did was simple but now it stays like new (almost).

Excellent idea. The downside being the part where everything has to be fixed and cleaned up. I know I have to do it though. Plus work on the rusted frame bits around the generator. I am planning to do a bit at a time as the urge comes over me. If I can find my can of CorrosionX I'll hit the panel right away. I'm ashamed not to have thought of that first.

What a dumb place to put electrical items; but on the other hand they actually survive it to a surprising degree.

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

 

Re: Boost switch, not boosting...

Reply #49
And I removed everything that was behind the driver's side rear wheels and moved them up into the "electrical area" at the front  of the bed.  All wires were long enough that no splicing was required.  Took while to verify where to drill the hole through the floor of the electrical area, but no problem.  Clean and dry and with the rest of the electrical items.

Brett
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020