4020 Diesel Not Firing

mmfarms · Oct 2, 2020

We have a 1967 4020 that died while idling, and now will not start. It is getting fuel at the injection pump. I cracked 2 injector lines and cannot see any fuel coming out there while cranking. I took off the return lines and blew them out, they were clear. I took the check valve elbow off and it had no debris in it and the check ball moved freely.

It seems like the injection pump has failed. It there anything else I can try before shelling out for a rebuilt? It just died like someone turned it off, no surging, no sputtering.

Tx Jim · Oct 3, 2020

'67 4020 should have IP with manually controlled fuel flow IE no fuel control solenoid. I suggest to check to be sure ring inside IP is moving when starter is engaged by removing timing window on IP. Have you attempted to start engine with throttle moved all the way down?

Dieseltech · Oct 3, 2020

Second what TX Jim said, make sure timing mark plate is turning. If not, either the pump hydraulic head has seized breaking the drive shaft, or the drive to the oil pump
has failed..

Al Baker(pumpman) · Oct 3, 2020

Over the years I think I have seen more head seizers at idle, than at high RPMs. Not sure why, but seems like if they die idling its a bigger chance of head n rotor locking up. Al

jlg_mmfarms · Oct 3, 2020

Lower ring in timing window is turning
while cranking. The upper ring doesn't seem
to have a line or anything to mark the
timing which seems odd. Pulled the back
cover part of the pump off, and it seems
like things are moving in there. Will try
to start with throttle all the way open
when it is back together

jlg_mmfarms · Oct 3, 2020

Here is a picture with the timing at TDC.
It appears the lower ring is centered in
the timing window, but there is no upper
mark

wore out · Oct 3, 2020

(quoted from post at 11:24:13 10/03/20)
<img src="https://www.yesterdaystractors.com/cvphotos/cvphoto58108.jpg">

Here is a picture with the timing at TDC.
It appears the lower ring is centered in
the timing window, but there is no upper
mark

To check timing you install a clear timing window (Stanadyne special tool) and check the mark you are seeing against the marks on the window.

jlg_mmfarms · Oct 3, 2020

It's centered enough that I dont think
timing is the issue. The pump is spinning
and its getting fuel.

Dieseltech · Oct 3, 2020

Your pump has a broken cam pin, confirmed by the cam mark no longer in the window. Not common, but I do see that on occasion on pumps I repair..

Sberry · Oct 3, 2020

I bought 2 kits. Wanted to have them on hand now. 2 things, 1st one I did we bought that upgraded deal all assembled, I forget et the name of the parts,, that waz a huge labor saver but I fixed another with the remnants of the kit and it was a bit of work to use that flat rubber coupling thing. What's the slick trick to putting it together, seems it took 2 of us messing with it a better part of an hour. Second, where you score any misc parts you might need?

4020 Diesel Not Firing

mmfarms

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Tx Jim

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Dieseltech

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Al Baker(pumpman)

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jlg_mmfarms

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jlg_mmfarms

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wore out

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jlg_mmfarms

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Dieseltech

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Sberry

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