After reading Scott's post, yes, the Detroits need a block heater at high elevations and cold weather but not because of being a 2-cycle. They don't have the air intake hot screens that other engines may have. I am now installing a tankless propane heater and 12V pump to heat and circulate coolant through the engine. Will also plumb it to replace the rear cabin furnace. Essentially, an AquaHot without the maintenance issues (hopefully).
Pierce
Pierce, please start your topic on your mod. I want to follow it ^.^d
Great idea, so heat exchanger in place of the furnace (s). Hmmm venting, deflector?
Thermostat, guess that can change. That looks like a small unit, is it a commercial, not your typical rv?
John,
Will start a post after I get it further along. It is a stainless, 8 liter/minute model. I also purchased a 12V hot water pump ($24) to pump the water through the existing hose (coolant, not potable water) going to the OEM water heater from the engine. I could have gone with a larger model but will try this one first. An additional door like the OEM heater will be installed in the door for access and venting. With the carpet lined separator removed and a thinner replacement installed, there is room to install it next to the other heater. If this works out OK, I will replace the OEM with a matching tankless. See heater at: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=151164521851&ssPageName=ADME:X:AAQ:US:1123 (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=151164521851&ssPageName=ADME:X:AAQ:US:1123)
I negotiated with the seller and got it delivered from a U.S. location in 3 days for $88 out the door.
I can't stand the loud heaters in the coach so hope this does the job.
Pierce
Scott,
Suspect your cranking problem in cold weather is cable or battery related. We also have #40 oil and in the teens in Yellowstone, the engine spun about as fast as in warm weather and without a block heater (burned out), it eventually started killing all mosquitos in the neighborhood. Good batteries with cable ends cleaned and flattened along with clean posts and connectors make a big difference. I like the military type connectors that Ken installed on their U300. A voltage check at the battery vs starter motor while cranking is a good indication of starting system health.
Santa Barbara is at sea level but our mechanical Detroits started within a tenth of a second even in winter with no block heater. Also used #40 oil.
We almost always dry camp so any type of electric oil or block heater is out.
Pierce
Pierce,
I have been thinking about this type of heating system for awhile now... I will be extremely interested in following your progress on this project! Sometime ago, I read an article (I think it was FMC magazine) about propane hydronic heaters that are being used in some of the new Class B's and C's that (I think) are made in Sweden. That got me thinking about the roll your own hydronic system that would be inserted into the motor aid loop (coolant) to add coolant preheating as well as cabin heat via lex tubing with valves and manifold.
Keep us updated! If anybody can craft a "Fire Department" approved heat source, I am sure it would be you... ^.^d
Don
Don,
There are a couple of propane fired engine heaters with 12V pumps out there but expensive. We have a fairly large compartment door with the OEM water heater on one side and the twin tanks with a carpet covered panel covering them just on the other side of the small separator. By removing the original panel and substituting a thinner panel, I can get the new tankless to fit. It's not so much the heater but the control knobs that stick out. The advantage of this location is there is already a hose from the engine to a heat exchanger inside the OEM water heater plus propane supply right there. So I can just bring one end into the new tankless and then send another hose back to the engine. With a couple of solenoids, I could also use a heat exchanger where the rear furnace is. Our home tankless makes much less noise than the U300s gas furnace, both inside and out.
The other possibility is to do the same for the front heater with long heat exchangers installed behind the sofa (convection powered) and a powered heat exchanger to force air out the stock outlets up front.
We have a couple of long trips coming up during the winter and want to have plenty of heat as well as starting the Detroit in sub freezing temps in Yellowstone. Since we almost never have shore power, this will be a good alternative.
Will start on the tankless project as soon as the engine compartment is done. I have finished most of it but the sides are hard to reach down to for measuring, installation, etc. I moved the 110V outlet a couple of inches to the other side of the bulkhead for the electric block heater and am running metal electrical conduit with the block heater cord inside. Attached is a photo of the top of the engine compartment. The insulation was in much better condition than I had imagined for everything but the top so just lightly scraped and vacuumed the old plastic covering off and then installed backerboard on top of it. For the top, I installed R19 Fiberglas and compressed it down to 1" with the backerboard. Works well on one short trip so far. I ordered a box of both #14 stainless screws in 2" and 2-1/2" length as well as stainless fender washers 1"ODx3/16"ID. Painted the backerboard with semi-gloss white (latex) so easy to keep clean.
Firemen do put fires out but also have been great off duty arsonists in Boston, Seattle and California's central valley. ;)
Pierce
Very interesting ideas for the heat exchangers an expanding the system. I wonder about the BTU capability of the tankless heater to provide enough heat. The attractive thing for me in thinking about this is a system that could provide say 10K BTU continuously to maintain an even temperature (just number pulled out of my imagination mind you, because this is an are that I have never delved into, but will eventually), VS the 35K BTU put out from our single central mounted furnace for short periods of time. As I understand it, you are going to keep your propane water heater for domestic hot water, correct? I believe I could mount a unit like the one you got (seems like a great price by the way!) on the passenger side aft joey bed compartment wall and extend the motor aid heater hoses through the wall to the propane tankless via a manifold. I just would need to figure out away to vent it properly. I have some ideas about that... I am a long ways away from anything but the daydreaming stage right now because I have about 5 major projects to accomplish need time we dock in our home port in San Diego. Let's see... solar, inverter, alternator to battery charge controller, various antenna reconfiguration for on the road internet and cell, battery monitors, cabinetry and desk (cabinets will run all the way from the passenger chair to the pantry), make some drawers, LED interior lights, I just have to live long enough ::)
Don
Don,
The 8 L/m tankless output is 16Kw or about 55,000 BTUs. If it works OK, I will probably go to a 12 L/m unit at 24 Kw/82,000 BTUs and may replace the OEM with one. Unless the manufacturers specs allow it, much of a distance horizontally will require a fan and sail switch wired into the heater.
Pierce
A less expensive and less time consuming modification would be to utilize the wasted heat from the diesel genset to heat the engine coolant. Just tie the genset's coolant in to the heater hose with valves. The genset should pump its warm coolant through the entire system, including the main engine. The genset can be charging the batteries as it's warming the coolant. You could turn on the defroster to start clearing your windshield too. Of course you can turn on the electric block heater or oil pan heater too... Last winter was cold enough to cause me to think about this stuff. :)
Scott,
Certainly a workable idea. The problem with a Detroit is all the normal block heater locations were used up in the Foretravel installation and their solution was to install it not down low in the block but completely outside the block and up high to boot. Even with a 1000 watt heater or larger, it still takes over two hours to warm the engine and even longer at high altitude in winter. It's been so cold and at 10,000 feet, we even had trouble getting the generator running with all glow plugs working, etc.
Since we installed solar and converted lights and TV to LEDs, we don't need to charge too much in the morning and generally let the panels work quietly in the background. National Park campgrounds are a mix of tents and motorhomes and the noise and smell (especially at altitude) from the generator is not friendly when others are out cooking breakfast.
The other big reason I bought the tankless is that I hate listening to the generator and both furnaces. If you step outside and feel the furnace exhaust, a high percentage of the heat is wasted. Even the OEM water heater is a noisy devil outside. I am looking forward to a instant and almost smoke free start at altitude in cold weather. Once I have full air, driving to the campground entrance, putting the engine on fast idle, letting Koda find a few bushes and then taking off. Should be about like a low cost AquaHot. Taking some time in planning has paid off nicely with the solar panel installation fulfilling all my expectations and hope this will do the same.
When you're retired, you've got nothing but time to have fun, tinker and hit the HF sales. ;D Will post photos as the installation progresses.
Pierce
On the DD in my BlueBird, the block heater is installed in a special semi-square plate just above the base pan. I've never seen anything else installed there except a heater. If the heater is not used, a block off plate is installed. What does Foretravel have installed in that location?
TOM
Tom,
The semi-square plate I'm thinking of is down low on the right side of the block looking forward. The air conditioning compressor mount bolts on there now. The hole for the block heater down low on the left side was no longer cast into the block on the silver 92 series. Ours is up by the left thermostat and comes in from the side. It heats the crossover pipe nicely.
Several months ago in Death Valley, I met a guy with a bluebird/wanderlodge with a bad block heater on his Detroit. Didn't want to pull it without the right tools in the park. Nice group of people.
Pierce
Pierce , I went and looked at mine after reading this post and found mine to be on the low side of the Bolck on the starter side, that is the way my Eagle was set up. So either the PO put it in or maybe the early u300 had them that way.
Andy,
Could you post a photo when you get a chance?
It sounds like that was another PO improvement on your coach.
Mine is located in the same place as Pierce; up high on the drivers side thermostat housing. This is only place I have heard of them being located up until your post.
Thanks.
Not specific to this topic, but different detroits will have different cold-weather behavior. Naturals (non-turbo) detroits have higher compression ratio and will start easier unaided and to lower temperatures.
There are some hi-perf DDEC boat engines that have trouble starting at 80degrees and put out a ton of smoke unless block heaters are used. Many people mistakenly claim these engines are worn out and in need of overhauls due to low compression.
I have an old 4-53 natural. It will start un-aided in a couple cranks down to 30-40 or so. Any lower and I just plug it in for a little bit.
A small shot of either is ok as well (or even wd40, etc).
My air conditioner compressor is located over the block heater as well. I just replaced the heater & had to remove the compressor to do it. Here are some pics. The first two are installed pics. The Prevost pic shows it between the belt. In the next pic it is right below the exhaust manifold at the end where the turbo pipe connects. The last is the heater without the plate. It is bent because the water jacket is shallow where it installs.
TOM
http://prevostcommunity.com/forum/threaddetails.asp?Category=General%20Discussions&ThreadID=750 (http://prevostcommunity.com/forum/threaddetails.asp?Category=General%20Discussions&ThreadID=750)
Detroit Diesel Engine Model 92 DDEC V8 turbo 585 HP - Diesel Forum - (http://www.thedieselstop.com/forums/f33/detroit-diesel-engine-model-92-ddec-v8-turbo-585-hp-213643/)
We must have different blocks or something. Tom, I can't see any installed photos in your post. Our AC mount is a flat plate and bolts against the block with no possibility of putting anything under it or running any wires out. Here is the link to the Detroit block heater that goes where the AC compressor is on ours. It states that it is only for Detroits without the AC compressor on one of the photos: Zerostart Heavy Duty Engine Block Heater Detroit Diesel | eBay (http://www.ebay.com/itm/Zerostart-Heavy-Duty-Engine-Block-Heater-Detroit-Diesel-/360417597567?pt=Other_Vehicle_Parts&hash=item53ea90187f) This would be the perfect location and I have looked to see if I could relocate the compressor. Andy, I crawled under the coach this morning but could not find a spot on the block on the starter motor side.
Zerostart Heavy Duty Engine Block Heater Detroit Diesel | eBay (http://www.ebay.com/itm/Zerostart-Heavy-Duty-Engine-Block-Heater-Detroit-Diesel-/360417597567?pt=Other_Vehicle_Parts&hash=item53ea90187f)
The longer block heater that goes up by the thermostat housing is the same exact heater used on CATs.
The cylinder head has removable plugs in the ends and would be a good spot for a recirculating type of block heater. Here is one with an internal pump. Would do a fast job of heating our engines with just a couple of hoses needed. Tank Type Engine Coolant Block Heater 1500W Diesel Kat's Brand Tractor New (http://www.ebay.com/itm/TANK-TYPE-ENGINE-COOLANT-BLOCK-HEATER-1500W-DIESEL-KATS-BRAND-TRACTOR-NEW-/121233966201?pt=BI_Heavy_Equipment_Parts&hash=item1c3a1b8479)
Pierce
Dave,
I did get ours going with the cycle crank sequence as you described in the teens but at 8000 feet. Melted a battery terminal connector doing it. It spun like a top and then one cylinder would catch, a few seconds later another would fire. Took 3 or 4 cycles and if it had been in summer, the fire lookout tower would have sent air tankers for all the smoke.
Also took several cycles to get the generator running.
Pierce
Pierce,
I guess we will have dueling pictures now. I can't see yours & you can't see mine! ;D
Yours is too close for me to locate what I'm looking at I think.
My pic of the Prevost is the best one of mine. The heater is the brown (rusted?) looking thing right in the belt loop. the electric cord is burnt off. You can see the front mounting bolts for the heater plate very nicely but the rear ones are in the shadow & not hardly visible. I may try to get a better pic of the one on my BB. Mine is a 1982 300HP (red) model BTW. It has been converted to a 350HP silver.
TOM
Don't forget that the two-stroke Detroit engines use straight 40 weight oil, and so an oil heater would also be an excellent idea in very cold weather.
Tom,
Attached is your photo. I swiped it off your site and processed it a bit to show the other bolts that were in the shadows before. The bolts in the four corners of the plate are the same four bolts as on our AC compressor mount. Your compressor must pivot lower on a different bracket. Anyway, it's a no go with that style block heater with our Foretravel.
One of these days, I will have to pull the mount off and see if it has coolant underneath.
Your earlier block may have had another spot on the lower left rear of the block. They changed the castings but not sure when. 71s did have it.
Pierce
John Fitz, I will get a picture on tuesday next week, I can not get into the storage on the weekends (sucks) So next week I will post a picture.
I have found that the circulation type heater works the best and they come in different wattages. I have found any time I have needed to heat up
an engine that won't start that it take 2 hours to heat up. I worked as a mechanic in -30 weather and the best way to make sure that every thing
will start is to make sure the starting system is in good shape. Batteries and starter must be in great shape with all the connections checked over
Are you familiar with Espar heaters? I have a diesel fired heater in my peterbilt for the sleeper and it will run you out if you turn it up too high. You can hardly hear it run. Mine is mounted under my bunk and just blows out into the cab.There is a small t stat that it is controlled from. They also have coolant heaters and heat and coolant heaters. Here is the link
Espar - RV Heaters, Motorhome Heaters - Eberspächer (http://www.espar.com/products/fuel-operated-heaters/applications/rv.html)
Stump, read this looks good. Says it will heat water and blow warm air at the same time ^.^d
For sure worth looking into, for an upgrade. ^.^d
The heater I have in my Semi is just a little smaller than a shoe box. The burner intake and exhaust are outside it has a draft inducer motor that also is the blower. It modulates as the temp comes up inside the cab the blower slows down to almost nothing. If the temp drops it will speed up and until the temp is satisfied. It probably burns a pint of diesel in a 10 hr period. Very very efficient the exhaust tube is stainless steel and the exit gasses are luke warm. Maby just cooler than a dryer vent a home.
Here is a video of the Hydronic model:http://www.espar.com/videos/hydronic-tech-info.html
I was told that my 6V92 has the plate to mount the lower right side heater but it would be very close to the compressor without changing the A/C bracket. The Detroit shop said the heater would work much better in the lower configuration and suggested that if I was going to be in cold weather very much to make that change. There are different heaters for each location. The cost of the electric heaters are each about $90 and both are 1500 watts.
I have started my coach twice at 10 degrees F with the heater on all night. It took several tries and I only ran the starter 10 to 15 seconds then let it rest for a couple of minutes. It was very slow to get rolling but it did finally start about the fifth try and it didn't hurt any of the wires or connections. I have started the coach a number of times when the temps were in the twenties but again I had the upper block heater on all night.
And Pierce you are so right. The concern that the Forest Service will think it is a forest fire is always a concern. It put out copious amounts of white smoke for a very long time.
The big problem is when there is no electric hookup. So far I have always found a camp site with electric in the cold weather, but I guess I could use the generator over night in a worst case scenario.
Exactly. Early in the morning when there is no wind, the smoke just spreads out until it covers a couple of acres. I hate thinking about it all the time. There is already enough RV
angst to go around and with some National Parks filling their campgrounds fairly early in the morning, the early bird gets the worm as far as a spot goes. Our mid-teens with snow was in summer at 8000 feet. After the block heater less start, we went over the hill to the Mammoth campground a couple of thousand feet lower. Many campgrounds have generator hours that start at 8am.
The links to the diesel engine block heaters or a combination coolant/air heater are good. The problem I see here is the price. They are not cheap but if within the budget, a better alternative to the 110V heater we have now. I decided to try my hand at the tankless installation as it was small, 55,000 BTUs and could do double duty as a block heater and a replacement to the rear furnace. I bought a 12V high temperature pump but may be able to use the stock booster pump that moves coolant up to the dash. The small pump I purchased only draws 2 amps so may be a better choice. With the existing coolant line to the OEM water heater just several inches away, I only have to run one return line. Separate lines with valves will have to be installed to route the water to the rear cabin's new heat exchanger where the old furnace was. With 55K BTUs, I can see a cold start within 30 minutes in freezing weather.
Before a trip, it's a good idea to turn on the OEM block heater and several minutes later, feel the area to make sure it's working. Just because the switch lights up, does not mean the heater is doing it's job.
Photos to follow later this week.
Pierce
Dave, the PO did the upgrade so I'm not sure what was done or how much it cost. I haven't looked into the engine that far yet. It does have aluminum valve covers but it has Jakes too so the valve covers are way higher than normal. It gets on down the highway pretty good for a 43K coach.
TOM
For cold weather boondocking I bought a Mr Heater "Buddy" propane powered radiant heater at WallyWorld last winter. It's small enough to put underneath my coach's oil pan, or up beside the oil pan sitting on top of a block of wood on the ground. I've never actually used it to start my coach but it did a great job placed on the curb beside my motorcycle shining radiant heat onto the crankcase. My motorcycle is kick start only and it refused to start on several occasions last winter, even rolling it down a hill and popping the clutch. This was with synthetic 10W40 oil in it! The Buddy heater can be run from a disposable propane cylinder internally, or from a barbecue bottle, or even from your coach's propane tank with a hose and adapter. It has a carbon monoxide shutoff and a tip over shutoff, so you can use it to heat the inside of your coach when boondocking, which I did do last winter while camping in the parking lot at work overnight during the big snowstorms. In really extreme cold weather you could use the Buddy heater to warm up your genset enough to get it started, then warm up your main engine until it starts... Hey, you gotta be prepared! ;D
Good Morning, I went over to the Coach and took a few pictures of my AC unit and my block heater John ask me to post some so here they are. Hope this helps
Hmmm, I replaced my dead electric heater last winter. The engine-driven a/c has never worked according to the PO, and we generally run the generator if it is warm enough to want a/c anyway. Maybe I should have just taken the compressor off and put a heater down lower where it would do more good. I've run the block heater all night, too, a time or two.
David,
Make sure the block casting is open for a heater before you buy one. Be sure to flip the switch off before you crank the engine. Only takes a short time in an air bubble to ruin it.
Tank type are about the same price and will work better with only a little plumbing involved: tank type block heater | eBay (http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2047675.m570.l1313.TR0.TRC0.H0.Xtank+type+block+heater&_nkw=tank+type+block+heater&_sacat=0)
Pierce
Thanks Andy,
It looks like you can put in a block heater on the A/C compressor bracket after all. I just looked at mine and I have the same bracket, just not block heater in the middle of it like yours.
I guess your PO already figured all of this out. Thanks again.
Pierce,
Have you figured out the plumbing so the flow goes through the block when the thermostats are closed on each head?
My understanding our thermostats are like a three way valve and allow the water pump to circulates coolant through the engine and bypass the radiator. So a recirculating heater would need to plumbed so it doesn't get shut-out by the thermostats. Maybe I'm mistaken and thinking about it wrong?
John,
Going to start installation in a couple of days of the tankless. Will use one existing line that goes from the engine to the OEM water heater's heat exchanger and bring back the return line probably to the one of the cylinder heads. Hopefully, I can go from head/side of the block to the other without interference from the thermostats. I could "Y" out of the engine and then back in if necessary. Will see in a couple of days.
The second part is to install a couple of valves so I can deliver water to where the rear furnace is. If that goes well, the front furnace is next.
Photos as I go.
Pierce
This sounds like a good upgrade that will be interesting to follow. It raises a question for me about the potential for using what we already have for a similar but less effective option. Since our current water heater will heat the tank with a coil of engine coolant, could any benefit be gained by installing a small circulation pump on the existing system that reverses the heat transfer from the water heater to the coolant loop? Similar to what an Aquahot does. Could that not help to raise the engine temp a few degrees with propane when the electric block heater is not available? It's probably a much less efficient option but would it work at all? As I think about it, it seems like the result might be a couple of degrees increase in engine temp with no hot water for a shower in the morning and a lot less propane in the tank. Has anyone ever tried it?
BDale,
All of our water heaters don't have the heat exchanger from the engine. To check if it does, open the compartment door and there should be a coolant valve with a round tag on it below the heater on the left side. The tag will say, "to the dash heat" or something like that. If you use a mirror, the hose connections can be seen on the rear of the Atwood as well. When the aux pump is turned on with the switch on the instrument panel, the pump below the PS tank in the engine compartment comes on and sends water to the front dash heater with a side trip through the Atwood water heater's heat exchanger. Yes, it would seem that if the flow of water could be reversed or a valve and a direct return hose installed, the engine could be warmed to a certain extent from the OEM water heater.
The small, high temperature pump I purchased (ebay-$25) could be put in the line and possibly reverse the flow back to the engine. The dash heater valve would have to be in the on position to allow coolant to flow through it and make the complete loop. The new pump draws 2 amps so could run all night. The aux pump is much larger and probably draws too many amps to run all night.
The main potable water tank is behind the water heater, pump and accumulator tank. The grey and black water tanks can be seen along with the liquid level senders behind the carpeted panel just to the rear of the OEM water heater.
Much of this is speculation and more will be understood as the project goes along. All above info applies to our U300 and may be only partially relevant to other models.
Pierce
I do have the heat exchanger loop that provides water heater & dash heat but I'm not aware of any auxilliary pump switch on my instrument panel. As far as I know, all of my coolant circulation is provided by a pump in the hydraulic system. I think my engine has to be running to circulate any coolant. I will try to look for that switch and, if I have it, will test the amp draw of that pump.
I tried it once in single digit temperatures. I ran the aux pump (had to have the ignition on) with water heater on for about an hour. I didn't see any increase in temperature on the dash gauge (and it's digital).
I don't think Cummins engines need the extra coolant pump. I've only heard of them on the Detroit 6V92s.
I ran across this company at work; HotStart. HOTSTART Engine Heating | Preheater Design & Manufacturing Leader (http://www.hotstart.com/en) They specialize in engine heaters.
Their general catalog lists block heaters for all kinds of engines, but page 50 talks about wattage required: 3 watts for each cubic inch of displacement.
Also says "V" engines should use forced circulation systems - same thing Pierce is talking about doing. I found it interesting (in a conflicting way) because they do make block heaters for V92's (page 42). I do think a circulation system would distribute the heat to all cylinders better - the goal is to get ALL the cylinders warm not just one or two hot.
http://www.hotstart.com/assets/Catalog-documents/IMC700-7-2014.pdf (http://www.hotstart.com/assets/Catalog-documents/IMC700-7-2014.pdf)
John,
The aux pump is only for the dash heater and will just boost the temperature coming out of the vents onto the windshield or driver/passenger so it's higher (less time for conduction/radiation loss on it's journey forward) and arrives faster than would normally be the case. Quite a few cars use them also. Sort of a "perk."
By the time the warmer coolant from the heat exchanger is forced by the aux pump up to the front of the coach, through the heater heat exchanger (trying to remember but think it's on the outside of the front bulkhead where it is cold in winter) and then back to the engine, there is not much more than lukewarm coolant there. Now, if you could take the coolant that has been warmed by the water heater exchanger and send it the 10 feet or so directly back to the engine, it could do some good. Not that it's going to work like a good block heater but if left on all night, think it would aid starting in the morning. Our Detroits don't have a heated intake screen like some others or glow plugs like the generator so every few degrees help.
Another possibility would be to install a much larger heat exchanger under the existing water heater, pump hot water from the OEM water heater through it and then send the coolant directly to the engine. If you got rid of the accumulator, you could install the heat exchanger in the available space. This way, you would use a larger percentage of the 12K BTU water heater to the engine. The way I am doing it will send just about all the 55K BTU output from the tankless heater directly to the engine for a rapid rise in temperature. (hopefully :) )
In ending, our 6 gallon water heaters are 12,000 BTU so if you could utilize 50% of that and send it to the engine, it would only be about 12% of the 55K BTU tankless water heater I am installing. Our furnaces are about 35K BTU so the tankless output may be able to replace the propane furnaces with heat exchangers, still burning propane but in a far quieter location.
Good topic!!
Pierce
Hey guys how about a forced air propane heater like the Red Dragon?
They say it can be used on any engine and bush pilots have used them for over 30 years. This 12 volt model is small and portable and I wonder if it could be mounted on a shelf in the engine bay and plumbed into the existing gas system eliminating a separate bottle. Would a 49000 btu forced air output in the right spot be enough heat to do the job? It uses about 1/2 gal an hour and has a high limit heat sensor. This one is a little pricey but is built very well built with a lot of safety features. Cheaper on ebay, etc.
I love this forum for throwing ideas around for mods and upgrades! :thumbsup:
Jerry aka Murph
12 volt D.C. Preheater with carrying case Model LT2-12MH-200C - Flame (https://www.flameengineering.com/product-detail.php?product_id=72)