SOUTHWIND COMBUSTION HEATER

RICKG · Post by **RICKG** » Tue Oct 26, 2010 10:39 am

NOW THAT MY M-38 IS IN THE RE-ASSEMBLY STAGE, MY PARTS SHELVES ARE BECOMING MORE SPARCE AND I'M RE-DISCOVERING SOME PARTS IN BOXES THAT I'D FORGOTTEN ABOUT-BECAUSE I DONT INTEND TO USE THEM. NAMELY A NEW STEWART WARNER SOUTHWIND 978M H-24
COMBUSTION HEATER AND STILL IN ORIG BOX THE ELECT FUEL PUMP,
CONTROL BOX AND WIRING HARNESS. ALTHOUGH I DONT INTEND TO USE IT, I'M CURIOUS ABOUT HOW/WHERE IT WAS TO BE INSTALLED,
HISTORY OF USE, ETC. (IF IT'S SO COLD THAT I NEED A FLAME THROWER IN THE CAB OF MY JEEP, YOU'LL FIND ME IN THE LIVING ROOM IN FRONT OF THE WOODSTOVE). ANYBODY?? THX, RICK

Post by **wesk** » Tue Oct 26, 2010 11:24 am

That is the most efficient heater built for the M38. It is mounted outside the windshield on the cowl in front of the driver. A duct ducts the hot air thru an adapter that replaces the windshield's lower center vent panel. A distribution duct on the inside provides for dispersing the air to the feet and for defrosting to the windshield.

The TB that covers it's installation is in the downloads section.
http://www.willysmjeeps.com/v2/modules. ... oad&cid=53

And on my photo storage site:
http://m38gasheaterkit.mypicgallery.com/

I have a couple of them. They do require periodic service and inspection to insure fuel pressures are correct and the burner can integrity is satisfactory.

RICKG · Post by **RICKG** » Tue Oct 26, 2010 11:53 am

THX, WES.. I'VE GOT THE DOWNLOAD-THIS THING IS A PRETTY NIFTY PIECE OF ENGINEERING ISNT IT.. SINCE I'M NOT GONNA USE IT I'M WILLING TO PART WITH IT (SELL OR TRADE) IF ANYONES INTERESTED.. RICK

Post by **wesk** » Tue Oct 26, 2010 12:14 pm

Do you have only the heater or the entire M38 installation Kit?

RICKG · Post by **RICKG** » Tue Oct 26, 2010 7:02 pm

besides the heater theres the fuel pump, control box, wiring harness.
i'll e-mail pics direct to you if you like since i dont have the posting stuff
figgered out

Post by **wesk** » Tue Oct 26, 2010 10:11 pm

Sure.

TomM · Post by **TomM** » Wed Oct 27, 2010 6:05 am

Does your kit still have the mount for the cowl, sheetmetal cover, exhaust stack?
Tom

RICKG · Post by **RICKG** » Wed Oct 27, 2010 8:27 am

tom, no sheetmetal cover, no cowl mounts, no exhaust stack.
i'll e-mail pics to wesk-maybe he'll post'em for us- rick

RickC · Post by **RickC** » Wed Oct 27, 2010 9:26 am

I have what I think is the diverter box that goes inside windshield available......
Rick

Post by **wesk** » Wed Oct 27, 2010 11:54 am

Rick's heater assembly and parts. The heater may be from a different vehicle due to the odd arrangement of the main and combustion blowers. The M38A1 installation has the electric motor of the main blower pointing upward.

Large photo is at: http://img.mypicgallery.com/m38gasheate ... c01077.jpg

Below is the M38 kit package and you can compare the heaters:

Large photo is at: http://img.mypicgallery.com/m38gasheate ... er-kit.jpg

Below is the M38A1 heater:

Large photo at: http://img.mypicgallery.com/m38a1gasheater/fig-13.jpg

RICKG · Post by **RICKG** » Thu Oct 28, 2010 12:04 pm

THX WES-THE COMBUSTION UNIT LOOKS CLOSER TO THE ONE IN
THE LOWER PHOTO DOESNT IT..
QUESTION: HOW MUCH FUEL TO YOU ESTIMATE ONE OF THESE USE PER HR??

Post by **wesk** » Thu Oct 28, 2010 1:18 pm

That's not a very common question. The quick answer is from 0.006 in lo heat to 0.029 in hi heat pounds per minute. Figure 7.5 to 8.0 pounds per gallon of gas.

RICKG · Post by **RICKG** » Thu Oct 28, 2010 2:35 pm

SO IF MATH DOESNT FAIL ME I GET A RANGE OF .045 TO .217 GAL/HR.
QUITE MISERLY, I'D SAY. THANKS, WES, FOR THE HISTORY. RICK.

Post by **wesk** » Thu Oct 28, 2010 6:06 pm

Actually that's not all history. These Stewart Warner (Southwind) heater and Janitrol's heaters are all still alive and doing well in light aircraft. I've been maintaining the 940 series for 20 years now. They are sensitive to a correct fuel pressure setting as well as a correct amount of combustion air flow. The older units with stainless steel burner cans need a periodic leak down check to prevent their deteriorating enough to give you carbon monoxide poisoning.
The modern units have ceramic combustion cans.