Choctaw H140 Manual

[DieselAddict]

Does anyone have the parts manual for the H140?

TM9-4520-271-24P

 

[DieselAddict]

I found the manual. Next question, Anyone had any luck finding the pump to motor coupling?

Item 5 in the image. I've used the numbers supplied in the manual and I've not been able to cross it to something that is off the shelf. I won't be surprised if they are custom but one can dream.

 

[Guyfang]

Well, the NSN and part number turn up three suppliers for the part.

DRS Environmental Systems
Science Applications Int.
Engineered Air Systems

The SMR code says it all. Even though the coupler has an NSN, the SMR code starts with XB. That tells you to NOT even try and order the coupler, but order the Kit, part # 60883-100. BUT, the kit part number will not show up in a search. Thats strange. Try the three suppliers.

I have very little tech data on the coupler. But if you want it, will call it back up.

 

[DieselAddict]

Thanks Guy,

That is what read in the -24. I was curious if anyone had ever pulled one and determined if it was a "standard" part or not. I have a few that have failed couplers. I think I know why. The preservative they put in there is pretty thick and has gotten gummy over the years in storage. One I powered up didn't spin up but hummed. I stopped it immediately and wiggled the fan back and forth by hand. After a few wiggles it broke free and ran fine. I suspect people manhandled them and likely snapped the coupling.

Once I am caught up on servicing generators I'm going to jump back on the heaters to see if I can get them going.

 

[Guyfang]

Ever think about 3D printing? That might be a good way to go.

 

[DieselAddict]

I'm thinking about that. Maybe machine one if I have to.

 

[Guyfang]

	OVERALL LENGTH	1 23/50 INCHES NOMINAL
	END ITEM IDENTIFICATION	ARMY SPACE HEATER, DUCT TYPE, PORTABLE; NSN 4520-01-439-1682
	PART NAME ASSIGNED BY CONTROLLING AGENCY	COUPLING, FUEL UNIT
	SPECIAL FEATURES	INTERNAL MOUNT ON FUEL PUMP SECURED W/SPRING PIN. SMALLER END IN BLOWER SECURED W/SET SCREWS; NHA CIRCULATING AIR FAN - PUMP MOTOR ASSY

This is all the tech data that I can find.

 

[DieselAddict]

That is helpful. Its the motor end that is slipping. If its secured with set screws there is the possibility it can be repaired. We shall see soon enough.

 

[cancunlarry]

That is helpful. Its the motor end that is slipping. If its secured with set screws there is the possibility it can be repaired. We shall see soon enough.

I have 4 units that have the same problem with the coupler #5. I was wondering if you ever found someone that sold the coupler or got one manufactered??

 

[JRKJeeper]

What issues are you seeing. It seems rare to have bought 4 units and all to have the same issue. Mine didn’t work either but I got it up going.

 

[cancunlarry]

What issues are you seeing. It seems rare to have bought 4 units and all to have the same issue. Mine didn’t work either but I got it up going.

The white coupler between the fuel pump and the motor is not turning. I took two of the pumps off and the square end on the white coupler is sheared off. The square part of the coupler slides into the motor. I assume the pump gets locked up or "gumed" up and the motor shears off the square end of the coupler.
A new coupler is $700 each. I was wondering if you bought a new coupler or had one made cheaper. I was also wondering what you meant when you said, " It's the motor end that is slipping". The first two heaters I took apart were sheared off at the tip of the coupling (square slotted end).
Otherwise, if the white coupler does not spin is it sheared off or have you found its slipping on the motor spindle?