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Greetings all, I'm curious if anyone might know or has tried to hook up a facet 24V electric fuel pump to act as a "primer" for a Southwind Arctic gas-fired heater. As well, would be ideal to configure actuation of the fuel priming towards the heater pump via the dash operated primer knob that is included in the Winterization Kit.

-I had the electric pump installed because the AC fuel Pump needs a rebuild and I am quite certain the cam lobe that actuated the stock AC pump is worn.

-Currently installed and running Facet 24V fuel pump

-Currently possess a complete NOS winterization kit with the Gas fired heater which included plumping ducts and wiring with all accessories, hardware, and hand priming knob.

Thanks, tom

Tom,
The personnel heater kit uses the fuel system pressure that is available to the carb. The kit instructions tell you to "T" into the carb float bowl inlet fitting.

As Joel said the primer kit is a stand alone system and it's only purpose is to help with starting the engine in cold weather by squirting an atomized blast of fuel in the front and rear halves of the intake manifold.


This is the install manual you should be using.


This shows the heater fuel line connection at the "T" which is inserted in the carb fuel inlet fitting.

The important thing to remember about gas fired heaters is fuel & fire.

The fire part has two dangers. Burning and carbon monoxide poisening.

The fuel part is a very important regulation issue. Pressure must be regulated to a narrow band. The heater's fuel flow valve regulates pressure at the burner to 1 PSI and the combustion air blower supports only the combustion chamber. Burning with an overly lean mixture results in shortened combustion can life.

Fuel inlet pressure at the "T" on the carb needs to be 4.5 to 5.0 PSI. Low pressure = lean and high pressure = rich. The heater likes anywhere from 1 to 15 PSI at it's fuel inlet.


You should also have this manual.



So if your current electric pump output is within the above parameters and your engine runs ok then just follow the heater installation instructions.

Fuel to heater is tapped at the "T" in my photo not from the carb's bowl. Imagine the engine's fuel pump then draw a line from the fule pump (whichever pump you are using to supply the carb) almost to the carb. Now make a "Y" from the single line you drew with one going to the carb and one going to the heater.

The heater does not have a fuel pump. It relies on the pressure from the engine's pump and has a fuel flow regulator that regulates the heater's fuel pressure.

The heater will function perfectly even if you do not install the engine's hand primer kit.

This diagram should help.

thank you Wes,
you cant get anymore succinct of an answer. your a gem !!

You can download all the pages for the installation manual from my photo web site:
http://m38a1gasheater.mypicgallery.com/

The first manual is here in the downloads section:

http://willysmjeeps.com/downloads/Heate ... tall.M38A1

Tom,
Your 978-M is the older version of the heater. The newer is 978-MC which has radio noise protection in it's wiring system.

WELL, got a wiring hikkup.

I got her hooked up and ready to fire....one problem. the instructions for wiring state that I am to connect hot wire to wire #11 (on vehicle) with a lead splitter that came with the kit. THen, to connect wire # 24 from the heater control box to #85 on the vehicle. I cant find wire #85 on the vehicle. On page 214 of TM9- 8014, the wiring diagram show a 4 wire ignition switch with #85 as vacant. The ignition switch I have on my M170 is a two wire solid enclosed switch.
Currently with just the wire #11 the heater fan and solenoids click / turns on regardless of ON/OFF position on the heater control box.
I've double checked my wiring and everything is where it should be.

Do I have the correct (two wire) ignition switch?
I'm perplexed about the #85 wire location for cold start hook up to the heater control box.

few facts.
-I have a neg ground cable cutoff switch installed
-I had installed a miil stock solid state turn signal group.
-I have an ignition lever switch that only has two wire connector accommodations.
-the vehicle is a 1955 m170 with Douglass Connectors and stock 24 VDC

Thanks for any advice.
tom

Tom,
You should have a 4 wire ignition switch. If you have only 2 wires then you have the wrong switch. The correct switch has wire #11 for power in from the regulator harness, #12 for power out to the distributor, wire #27 for power to the instruments and finally wire #85 for accessoried.

You can still make the 2 wire switch work. If your instruments work only when the ignition switch is on as they should then it will be obvious that wire 11 is power to the ignition switch and is tapped per the heater drawing for it's power source. The other wire off your 2 wire ignition switch is then obviously powering up both your #12 wire (Distributor) and your #27 wire (instruments). Therefor you will need to connect the heater wire originally calling for attachment to wire #85 to this same second wire that already has #12 & #27 connected. How you accomplish this mechanically is up to you.

I am going to assume you have the early heater control box in which case either your safety valve prime switch is closed or the heater's flame detector switch is closed allowing power to the fans before you are actually ready to start the heater. There should be three wires exiting your control box that do not go to the screw on connector. They are for the #11 wire, #85 wire and the fuel safety valve.

thanks for the reply Wes, it seems that I've discovered the problem with the fan turning on while the switch on the control box is on the off position. I noticed the flame detector switch was not in contact with the A/B spring that activates the micro-switch to the fan and safety valve. I carefully removed the Flame / Detector to inspect the quartz rod inside. Well.....@$
(90@$(@#OL!!! the infamous quartz rod came out in pieces !!!!

I had foreseen this...... #@$%@ shame and pissed.

I had a feeling this would be the problem. Must have broken in transit of dropped , I dunno.. anyway. might you have any idea where I might find this very scarce part?

I'm livid.

tom

SW# 486901 5 7/16" long
SW# 484092 6 1/8" long

?????

for the southwind model 978 M-R ...it states the part # in the tech manual parts diagram as part # 484092

the outer metal housing that encloses the quartz rod is appx 6- 5/16" long by eye.....

The M37 guys had luck with this guy for parts:
Try Patson parts and eqpt. Anchorage Alaska, 907-333-5682

thanks again Wes, will give them a call....