72 ford 4000

[Con4000]

Default 72 ford 4000 heater plug
Hi all, I have a heater plug in the back of the manifold of my ford 4000, it has a cable from the key switch and a pipe that carries diesal from the tank, I'm just wondering what is the correct lay out for the pipe work, in my ford there is a small fuel resiviour that has 3 ports, 1 on top that returns to tank and 2 on the bottom, one is the return from the injectors and the other seems to b running to the Heater plug although it never seems to have any diesal in it, is this resiviour needed or how should it be connected properly
Thanks

 

[HakanTh]

Hi

Your pipe work seems to be correct (take a look at attached pdf, from New Holland Online Catalog).

The reservoir is needed.
When you pre-heat the air in the manifold before cranking the engine, the thermostart is fed from the reservoir which contains diesel from the latest engine run/crank.

It would be tricky to get diesel to the thermostart without the reservoir, even when cranking the engine. You need to have a return line to tank all the time, but a line to the thermostart is only needed when heating. Perhaps it could be arranged by letting the return line first pass a T-connection for the thermostart and then continue to tank, but then you would only have the diesel remaining in the line up to tank for the pre-heating.

Your reservoir and/or the line to the thermostart is probably gummed up inside. Let them soak in gasoline over night and blow through with air.
The reservoir cannot be taken apart.


By the way;
I am thinking of putting a shut-off valve on the line from the reservoir to the thermostart. A friend of mine experienced a cracked piston on his TW-35. There was a huge soot build up that had cracked the roof on the piston. He had a leaking thermostart and that probably caused it.
A shut-off valve would be an easy fix and easy to use.

 

[RickB]

The reservoir is not needed and was eliminated sometime in the late 1970's. A dedicated tube runs from the thermostart unit to a tee near the fuel tank where it connects to the injector return line. See a 3910/4610/3930/4630 or similar model.