We're currently in St. Peters, MO and if you have been following the national news you know that most people are predicting major riots in the area when the Grand Jury releases their conclusions on the death of Michael Brown. Ferguson, MO is about 15 miles or so east of here. Temperatures are mostly going to be under 50 degrees. Will it hurt anything to leave the block heater on all the time?
Lest anyone worry, we DO NOT expect any rioting here, but we're also not going to wait until the rioters are right outside the door. We're monitoring local news and do have a plan to go elsewhere should it become necessary.
I don't think it will be a major issue to leave the block heater on as long as the temperatures stay cold. We've left the block heater on for a month at a time with temps down in the single digits night and teens day and it seems to be just as good as it ever was. I started the rig up and drove it 25 miles this last Wednesday. Had the block heater on overnight.
We leave the block heater on our Dodge pickup with a Cummins diesel just like our RV all winter and have sincd 1994. But we use that more often in the winter.
Craig
We would leave block heaters on constantly on plow trucks stored outside. The only heaters you have to worry about are the ones that heat the oil. Yours heats the coolant.
Keith
Thanks. That's pretty much what I expected, but I thought I'd better ask those who know a lot more than me.
Just be aware you're going to use a LOT of electricity. I forgot I'd left mine on for two weeks and almost had a heart attack when I got my bill. If you're in a campground then it's only an ethical issue. I'd offer to pay.
Why do you have to worry about heaters that heat the oil? Do the heaters get the oil hotter than the engine does?
David, if you want the engine to be warm for starting then 24-48 hours on the block heater should be sufficient especially at 50°. 48 hrs last winter here at -18 and it started right up.
A 2000 watt heater would cost 25¢ an hour to run, probably more in most places. $6/day adds up in a hurry. They are probably not on all the time.
Roger
If I remember correctly (NOT a safe assumption), I have a 1000W heater. Current temp is 54, so I'm guessing that the heater probably isn't running much. Temperatures are going to be all over the place for the next few days, so I'm going to leave the block heater on. No word on when the Grand Jury will release their findings, so things are still pretty peaceful here.
I would have the heater on when ever the temp is below about 40 deg. That engine should start anytime above that. I've started our Cat at temps well below that. Your call, whatever makes you feel safe and ready. ---- Have a great day ---- Fritz
My 6V92TA with straight 40 weight oil in it will start on one battery down to at least 42 degrees. It'll start with all three batteries when it's a lot colder than that. It's a rough start with a lot of white "smoke" unburned diesel vapors and rough running and of course it's very loud for a bit until the computer senses the engine has all cylinders firing, then it smooths out and sounds almost normal. I'm sure it's not good for the engine to start it up cold with thick oil but if ya gotta, ya gotta.
I'm still curious why you have to be careful with oil heaters. Can they heat the oil hotter than the engine does? I'm planning to install a plug type heater in the oil pan drain on my next oil change. I was considering getting the most powerful plug heater but now I'm curious and considering possibly buying the least powerful plug heater if overheating the oil is a possibility. Is there any evidence of this? The most powerful oil plug heater I've found is 300 watt.
Concern re oil heaters is possibility of condensation inside engine, with possible corrosion, if left oh continuously. Pad based pan heaters in general preferred over stick heaters, but of course more $$$
I've never heard of a thermostat controlled block heater on a Foretravel. I know mine runs continuously when turned on.
Happy to see this discussion. I found the outlet under the foot of the bed, the plug (not plugged in) and the switch for the outlet (with red light) about 3 years ago! ;D
I figured it was for a block heater, but never bothered to test it to see if it works. Today I Plugged it in through a Kill-A-Watt meter and found it draws 11 + Amps and uses about 1,390 Watts. Will start using it; and could have the past few days in Oregon.
Dick
This is correct for the block heater on our coach as well. The cord is just a cord with with a grounded A/C outlet plug on one end and a threaded coupler on the engine end. The heater itself is just a simple resistance loop like the electric element on our house water heater. When we got the coach, the cable was unplugged under the bed and at the engine. Both the engine and coach ends were somewhat melted, though the engine end was so far gone that it was just a lump of stuff. I had a hard time finding the heater location on the block... I theorized at the time that the block heater must have shorted out and caused the meltdown. The A/C outlet under the bed appeared to be undamaged. I bought a new block heater and cord from Cummins... When I had the baseline service done on our coach up in Colton CA (all fluids and filters changed and a couple of misc items), I discovered to my chagrin that neither the new block heater or cord was with us >:D >:D Anyway, after we got back from Texas, I cleaned the melted gunk out of the terminals at the block heater end and plugged in the new cord and was surprised and happy to find the the block heater got hot, but cord stayed relatively cool. Moral of the story, I am reluctant to just turn it on and leave it on unless the temperatures are nearing freezing and staying there. There ways of safeguarding the system though...
this site has thermocubes (discussed elsewhere on the forum), heavy duty digital timers, block heaters, oil pan heaters (including a couple of interesting magnetic models (that only work on steel oil pans, of course).
Auto Air Conditioning Parts & Heaters by Auto Cooling Solutions (http://www.autocoolingsolutions.com/index.php)
Don
I turned the block heater off for now, but I'll turn it back on again before we head for bed. Supposed to be near 60 tomorrow, but then the highest temperature predicted is 43.
In the 40-60 degrees F range, an hour or two is PLENTY of block heater time.
David,
If your Detroit has the block heater up high on the thermostat housing, it will take 3X longer than the Cummins block heater. If fact, the Detroit thermostat housing location means it's not a real block heater. Some Detroits have the heater under the AC compressor to block mounting plate low on the right side of the block. They work well.
Pierce
Pierce, I think mine is the same as yours, about eye level on the left side as I face the engine from behind the coach.
David,
Yes, that is the thermostat housing location for the heater.
If it's working, after about ten minutes, the crossover pipe should be quite warm to the touch. If not, check the outlet where it plugs into up high forward in the engine compartment. Pull the plug out and check for overheating. Mine failed at the connection at the block heater and the supply voltage fitting. It corroded and then overheated.
New block heaters share the same part number as the straight element CAT heaters and are available in several different wattages. Also, they are of slightly different construction so should be less prone to corrosion. I chose 1000 watts for ours. They come complete with new wires. Changing on a cold engine will minimize coolant loss.
Remember to switch heater off before cranking. At 50 degrees, one hour, 40 degrees, 2 hours at lower elevations, longer if higher. Our engines don't heat intake air like some others.
Found a NOS on eBay for under $40 delivered. Thermostat location heater is different and not interchangeable with AC compressor location.
Pierce
How do you know that the two cycle Detroit Diesel doesn't have an intake heater? I was attempting to verify that but I can't find any statements supporting that conclusion from Detroit Diesel or anywhere else. Why does my voltmeter go way down when I turn on my ignition key and the red lights on the dashboard come on for a few seconds if there's no intake heater or glow plugs? Also, when I attempt to start the engine before the red lights go out it just cranks and cranks but doesn't actually start until after the red lights go out. It sure seems like it's waiting for something to heat up before it can start.
Scott,
I'm not going to swear your engine 6V92 doesn't have an intake heater but I have never seen one on a DD in the 40 years I've been wrenching. Since no major truck or bus manufacturer used one, I would think Foretravel didn't use one either. Again, it's certainly not out of the realm of possibility, but if you have one, please take a pic! Lot's of us old guys would like to see it! :o :o
Don't know why there is such an amp draw when you turn the key either. Perhaps someone with more Fortravel experience can answer that.
TOM
I presume the intake heater would be underneath the supercharger where I can't see it? There should be some heavy gauge wires going to it judging by the amount the voltmeter goes down when I turn the key on. I never realized the voltage went down when the key was turned on until I modified my voltmeter to stay on all the time, even when the key is off. It's been a much more useful and informative instrument since then. I installed a single pole double throw switch so I can compare both banks of batteries with the same gauge, which is also very useful and informative, especially when boondocking. I found a two stroke Detroit Diesel forum and asked about the intake heater. Hopefully someone on there will know how to verify whether or not the 6V92TA has an intake heater.
The problem with heaters in the oil is the oil can be carbonized if the element gets too hot.
Keith
Well I have pulled my blower to inspect the intercooler (pic attached) which is directly below the blower. There is no electric heater in there and I think I can tell you why: It's a very oily space. The element would get coated with oil when the engine is running. At the next startup that element would probably catch fire or at the least smoke like crazy.
I think the voltage drop has to do with 23 year old wiring and having 30 feet of cable between the battery and the dash.
So why won't the engine start if I attempt to crank it before the red lights go out on the dashboard? If there's no heater what is the engine doing for that period of time? Out of curiosity I just turned my ignition key on and watched the voltmeter drop a full volt immediately. There has to be something on the other end of the 23 year old wiring that's drawing a lot of current. It's not the vacuum pump and I don't hear any fuel pump or other pumps running and it's not below 40 degrees so it can't be the heater in the air dryer and it's not the mirror defogger or anything controlled from the instrument panel. Even if it's the 23 year old wiring that still doesn't explain why the engine won't start until after the red lights go out.
If you don't believe me, take a look at your U300 schematic and try to find a hot screen or glow plug on the 2 cycle. Our Detroit waits about a quarter second after hitting the start postion and then cranks. ECU may be responsible for any delay and current draw. Low enought voltage will cause the engine to die unlike the mechanical Detroits. Even though the entry step is not electric, it still requires a certain amount of voltage/current to trigger the retraction.
Mechanical Detroit 2 cycles have no delay and will normally be running in one tenth of a second after hitting the starter button. I have never had one start slower in thousands of starts in the fire service.
Typical hot screens are found on Diesels like Perkins and others. They may be located before the turbo. Pre-combustion chamber diesels usually have only glow plugs but in some cases, also have heated screens to aid starting. Our diesel generators are pre-combustion chamber designs and have glow plugs. They usually have up to 21:1 compression ratio (may be 4 or 5 points higher than direct injction engines) and are generally about 5 percent less efficient than direct injection engines.
After recommended hours, the turbo should be pulled along with the blower and the aftercooler cleaned. They may build up deposits and not be as efficient in cooling the hot air from the turbo and blower. Would look up hours but sitting in a hotel in Detroit with slow internet and don't want to go to the car for the MiFi card in the rain.
Pierce
It was a question, not a case of disbelief. I can't come up with an easy answer for why the voltage goes down when I turn the key on and the engine will crank but not start until the red lights go out. It's often up to 20 seconds before the lights go out and the engine will start. If it doesn't have a heater it must be doing something else that takes a lot of time and electricity before it will start.
So, in reading your post, your starter motor will operate almost immediately after turning the key but not fire/start until up to 20 seconds later?
The turbo 6V-92TA has a lower compression ratio (16:1) than the non-tubo engines so generates less heat from compression and is slow to get all cylinders firing in cold weather. With the temps in the 60's, our engine will start on one cylinder, pick up another one or two quickly and then the last several a few seconds later. Drop the temperature another ten degrees and the first cylinder to fire will delayed a few more seconds and with the temperature down in the 40's, it may cranks quite a few seconds before the first cylinder fires. A very poor block heater location means several hours of operation before the engine will start reasonably quickly. The resuling white smoke is from the unburned fuel in the last cylinders to fire.
Older mechanical engines had a spring loaded cap on the blower housing to allow ether to be sprayed to aid starting. Not used on RVs as one ether application on a hot engine may bend a connecting rod or break a ring from an explosion very early on the compression stroke. This applies to all diesels.
Slow starting in any diesel may be at least partially aided by having clean terminals and good batteries and low voltage drop between the start batteries and the starter motor. Faster cranking means compression heating will be greater in a shorter period of time and the cylinder with the best injector pattern and highest compression will start firing sooner.
Pierce
It still takes a few seconds to start even when the engine is warm. I've only accidentally done that a couple of times, usually after I just got out of a gasoline powered car and forgot I was starting a diesel and had to wait. I'll crank it immediately the next time I start it just to prove it to myself. As I was thinking about this I realized that the supercharger will make intake heat by compressing the air into the intake, which is why there's an intercooler right beneath the supercharger, to get rid of the heat. It's a law of physics that there's a direct relationship between compression and heat... but that still doesn't answer my question as to what requires electricity and time to start the engine if there isn't an electric heater.
Scott,
You either have an injector(s) leaking diesel into the cylinders when turned off, air getting into the loop or low compression. Try using the hand pump for 30 seconds or so. Check O rings on hand pump. Look at the check valve by the primary filter. Ours was cracked.
Absolute best is to pull the fuel return line off the engine, attach a 10 foot line and place it below the surface of a container partially filled with diesel. Turn engine off at night and start in the morning with someone watching for bubbles in the container.
Pierce
ECU will draw quite a bit. You can hear it buzzing if you walk back with the key on.
The engine starts in a fraction of a second if I wait until the red lights go out before I start cranking. If I start cranking before the red lights go out it just cranks and cranks until the red lights go out, then starts normally. I doubt the computer can draw an 8D battery down a full volt or more. It's not exactly a liquid cooled mainframe computer! :)) I don't think there's anything wrong with my engine so I'm definitely not gonna mess with it. It's been this way the whole time I've owned it. It has very strong performance, especially at high altitude, and much higher fuel efficiency than expected. People are always blown away when I tell them what I get for mileage.
Scott,
I just don't have any red lights so can't figure that one out. Perhaps it has an electric fuel pump added as I have seen buses with one. Where are the lights? Do they appear to be added or OEM?
Does the voltage go up after the lights go out?
Pierce
Not sure of the electrical circuits made ready at the ignition turn on but it seems to be quite a bit.
Second thing I would check is every electrical connection in the engine battery circuit.
Every part new condition then monitor the drop. In my Foretravel days I would check/remember numerous duplicate coaches to see if I get similar results.
Maybe someone added an oil pressure pre lube that will not let the coach until it has oil pressure. That would account for a voltage drop with a motor running a pump.
The red lights are built into the instrument panel and the same lights were on the 40' 1991 U300 I looked at before I bought my 36' coach. The lights say: "Check Trans", "Stop Engine", and "Check Engine" and they go out after a few seconds, then the engine will start normally. The 40' coach behaved the same way. I remember the seller waiting a few seconds until the lights went out before he started it. I also looked at a Vogue with a 6V92TA and that seller waited a few seconds before starting it. The Vogue didn't have DDEC like the Foretravels though. There are no pumps running. I have excellent hearing and I've never heard anything other than the vacuum pump come on with the ignition key. The wiring is in good condition and the coach cranks and starts just like it always has. There's nothing wrong with it. The next time I'm at a Detroit Diesel service center I'll ask why there's a starting delay and a voltage drop if there supposedly isn't any heater. It's not really a burning question that needs an immediate answer. I've just read that the Detroit doesn't have a heater so many times on this forum but I can't find any evidence either way and mine certainly acts like it has a heater... so that's why I asked if you guys know of any evidence. It's not that I don't believe you. I'm just asking how you know this because I sure can't find any evidence either way.
"The red lights are built into the instrument panel and the same lights were on the 40' 1991 U300 I looked at before I bought my 36' coach. The lights say: "Check Trans", "Stop Engine", and "Check Engine" and they go out after a few seconds, then the engine will start normally." That's the way things are on my coach, too. The PO told me to turn the key on, wait for things to settle down, and then start. I turn the key on and after a few seconds those lights go out and then I start the Detroit.
John,
How long did it take you to pull the aftercooler to clean it? How dirty was it? If dirty, any improvement after doing it? Any problems with the turbo clamps? Parts/gaskets ahead of time?
Pierce
I did it 10 years ago so it's a bit of a faded memory. A mechanic suggest checking the intercooler for clogging; thought it might be the cause of overheating. Intercool was clean when I pulled it. I don't remember how long it took, but I do remember it was a pretty straight forward operation and wouldn't hesitate to do it again if I needed to. One exception is the exhaust ring that is between the turbo outlet and the exhaust flex that goes to the muffler. That attachment joint between the turbo and the ring was very difficult to separate: hours of propane torch heating, beating with wedge and hammer, applying diesel to joint, repeat, etc. etc. over several days. I even consulted the Bus Nuts forum and they confirmed yes, it's difficult but perseverance is the key - and they were right. I managed to not damage either half of joint. Reused all the original band clamps. I brought in the turbo, blower and intercooler to the parts guys at the Tucson Williams Detroit Diesel for them to evaluate and they said they all looked good and didn't need to be replaced or repaired.
I remember using new gaskets but I don't remember any details about that - it seemed like Williams had it all in stock. That might be different today - these engines are getting more rare. Coach ran just the same once it was back together.
Not to change the tone of the subject, but I have a question regarding replacing my block heater. I have a 92 Grand Villa with the B5.9 Cummins, my block heater is located in a freeze plug on the drivers side of the engine. It no longer works. I have tested the electrical cord and that is good. Does anyone have a suggestion as to a brand or seller that carries a high quality block heater. Do not want to put in a cheap heater after having to replace all the anti-freeze. Also is there any reason I should not use ES complete oat anti freeze? As always thank to the knowledgeable foretravel owners for your help.
Howard Reinhardt
You and I have pretty much the same coach. When I turn my block heater on the switch at the bottom of the bed on the co-pilot side has a light that comes on inside it. Is that the way yours works? Have you tested to make sure that there is 120vac at the receptacle where the block heater plugs in? You should also be able to check the resistance of the heater (measure from prong-to-prong on the electrical plug). It should be 4 or 5 ohms I think. If it's infinity then the unit is open.
I would contact Cummins. You will need your EID (engine ID) number because if you don't have it they'll tell you that every engine is different. But I suspect any block heater for any Dodge in the early 90s would do the job.
Craig
Hey Craig. Yes we do have pretty much the same coach. I do have the block heater switch at the bottom of the bed, but the red light on just means the outlet in the engine compartment that the block heater plugs into is working (on). Unplugged the heater and tested the plug - got OL - no resistance whatsoever. Plugged it back in and unhooked from the block and tested cord for voltage - 120 volts. could not get my tester to touch the actual prongs of the heater to check for resistance but I believe testing the electrical plugs prongs (as you suggested) was sufficient to test for resistance. I will probably contact cummins tomorrow - just don't want to buy a cheapo (poor quality)heater. Thanks. Did you ever put in a resonator.
Howard
Thanks Craig - Cummins did have the block heaters and cord. They even had it in stock.
Howard