Tested fuel burning heaters today

[cranetruck]

Thanks, and after reading your PM again (about too much fuel causing smoke and shut-down), I now need to recheck my fuel valve calibration, which is on the high side, perhaps just a few cc's per minute is enough to make it overheat. The table above specifies 7.5 +-1 and my setting is more like 11 or 12.......

 

[nf6x]

When I tried to bring up the fuel-burning heater in my second M109A3's van body, it took me quite a while to get it to light the first time. In the process, it flooded out and a bunch of fuel accumulated in the bottom of the exhaust pipe (which is designed very nicely for fuel accumulation in the M109A3! ). Once I got that heater to light up, the hot exhaust flowing over the pooled fuel in the exhaust pipe made just the right conditions for generating smoke. It really made a huge, impressive cloud! I wish a had a camera handy for that.

 

[steelsoldiers]

Any further progress here Bjorn? I am just starting my research on fuel-burning heaters since fall is upon us and winter will be soon to follow. I am planning on some excursions into the WV mountains and would like to stay toasty warm. Running Bkubu's heater at Aberdeen this year sold me on the idea! That thing was incredible.

Have you found anyone in particular that is a good source for parts?

I am looking for the heater: 2540-01-194-3323 and the control box: 2590-01-125-6154. I already have the fuel pump, the filter, the shut-off valve, the plumbing, and the wiring harness.

Thanks.

 

[cranetruck]

Time flies Chris. So, which vehicle will this be for?

Recalibrated the fuel control valve and got the coolant heater started, but was sidetracked to work on the fuel selector valves for the 50 gallon tanks. Just finished the last of the electrically heated fuel lines yesterday so I should be able to get back on the heater soon.

The cab heater has been running for some time and starts consistently after about 45 seconds.

None of my heaters are as new as the one you are looking for, all mine have the "-00" in the NSN number.
Can't find parts anywhere, but I have been successful "rebuilding" several fuel valves and have one heater apart, waiting for a new wick. After it gets back together and tested, it will be sold, possibly on ebay. The NSN for it is 2540-00-933-8916 (20,000 BTU/hr)....

 

[ARMYMAN30YearsPlus]

I have an old Gasoline fired shelter heater that I have lugged around for 20 years worth of PCS's and now that I have an M109 coming home it may get pulled out, tested and installed it that van.

 

[area52]

Hey Bjorn,

I would be interested in that heater if you want to sell it when your done with it.

 

[WillWagner]

Hey Chris, I have a few M151 heaters..coolant type...20k BTUs. 100.00 plus shipping.

 

[steelsoldiers]

Thanks Will, but I'm looking for the personnel heater, not the coolant heater.

 

[area52]

Thanks Will, but I'm looking for the personnel heater, not the coolant heater.

I think the M151 heaters are using coolant as a heat source and thats what Will meant?

 

[cranetruck]

Hey Bjorn,

I would be interested in that heater if you want to sell it when your done with it.

I'll let you know when it's put back together and tested.

 

[cranetruck]

Found wicks from this seller: item#350106053163
I was able to install one 1/8" dia wick, about 2 inches long, in the 20,000 BTU heater, but haven't tested it yet.
The 30,000 BTU South Wind heater has a wick, which seem almost an integral part of the ceramic vaporizer, so I'm not sure how replacing it will work.
I also have a Benmar 30,000 BTU unit, which still has to be tested and it at first glance anyway, doesn't use a wick, which is a plus.
When I get motivated to work on the heaters again, I'll post the results.

 

[ida34]

I have been working on mine all weekend. I got one control valve working within specs on high but nothing on low. I had a valve from a brand new coolant heater and it did not work at all. Not a drip came out. The original was leaking externally so I put the new o-rings from the new valve into the old valve. Then I get nothing out of it. I am going to have to pull them apart again. The only thing I can think of is the shut off valve passage is blocked with something I knocked loose.

 

[cranetruck]

Chuck, take a look at the "orifice plate", hold it up towards a light and make sure the holes are not clogged. It was a problem in at least one of my fuel valves.
It's the plate sandwiched with gaskets and held in place with three screws on the end, opposite to the fuel delivery adjustment screw.
I would post a picture, but my decade old computer is giving me problems off and on and this seems to be one of those moments.

 

[ida34]

I know the plate and they are clear on both valves. Something has to be obstructed in the valve body itself. I did not pull out the valves themselves. Have you pulled them out? I do not see any easy way to do it. It looks like I have to pull the guts out of the solenoid.

 

[cranetruck]

I routinely take the solenoids out and apart. Always energize the "S" solenoid when testing flow. Energizing both the "S" and the "R" solenoids will give you the "HI" flow rate.

 

[ida34]

I checked my solenoids and found two to be sluggish and not always opening all the way. I put the best two on the control valve and tested it. Everything was fine. Flow was within specs for both low and high settings. I used the pump on the truck and just put the switch to run to power the pump. I then jumped the solenoids to the batteries. I put the valve on the heater and hooked it up and nothing. Power going to the pump. The housing had good ground and there was power to both solenoids. It would not start so I pulled the tube from the valve and the heater and nothing was coming out. The only thing I can conclude is that I do not have any good solenoids and the shut off solenoid is hanging up. I am out of parts and patience with it.

 

[cranetruck]

The procedure you describe is close to mine, but I also bleed the fuel line from the pump to make sure all air is out each time I try a new valve...hate running that igniter with no fuel, even thought about adding a delay circuit for the igniter to let the wick soak up enough fuel for a more reliable start.
As far as ground, the heater is grounded via the cable and the control box, so the control box ground is vital.
I too get discouraged from time to time, that's why there is such a long time between my postings on this subject, which started over a year ago.

 

[cranetruck]

To gain confidence, I run the one working heater I have from time to time. Started the cab heater this morning (it took 75 seconds before it ran on its own) and it's running as we speak, now 55 minutes later.
Some observations, the exhaust pipe gets very hot but the heater sheet metal enclosure stays cool to the touch. It sounds like a vacuum cleaner when working (somebody else made that comparison and it's striking).
There is no visible exhaust.
Even wide open as it is and without duct work, the crew area is warm and the windshield defogged within 20 minutes.
Now, if I can only get the coolant heater working, visible by co-driver's seat in one image...

 

[cranetruck]

Shut it down, flipped the switch to "OFF" and it ran for 110 seconds before turning itself off.
Flipping the switch to "OFF" turns off the fuel pump and de-energizes the "S" solenoid. The heater then runs on its own to use up any left-over fuel.

 

[cranetruck]

Getting psyched up to work on the coolant heater again, checked my records and the last time it was running was on 09.07.08. It was then running on its own after 50 seconds, but smoked a lot, so I shut it down. It kept going for another 3 minutes while smoking and I hit the emergency off to terminate the test.
Since then I have worked on several other projects and only today tried to restart it. It didn't start after a full 2 minutes, so I'll be removing the control valve again tomorrow to recheck calibration.