M108SHC intermittent starting issues, random in nature, electrical?

[TxCuzzz]

So the M108SHC has an intermittent starting issue, where it randomly decides it will not start. Sometimes it works fine for days, then other times, you turn it off and come back a few minutes later and it wont start.

Today is a day it wont start. The ambient temperature is 55 degrees, clear beautiful day. Engine cranks, but will not start. Full of diesel, fuel supply pump working (you can hear it clicking), pressurized fuel coming out of rail going to injectors (cracked the nut and cranked motor). Battery has a full charge, and sometimes even with it hooked to a charger/starter it just wont crank up. Not a battery issue, or a starter issue for that matter.

Nothing to indicate it will not start but it wont. I am thinking it is an intermittent electrical issue, but have no idea where to look. I do not see how it can be a fuel delivery issue with pressurized fuel leaving the rail.

Wiggled all connections i could find, pulled and reset all fuses i could find, no luck.

It seems to have a mind of its own as to when it wants to work or not. Very frustrating. Once it starts there are no issues and it runs like a top!

Tried to go over the parts diagrams online, but if you have ever done that its like finding a needle in a haystack.

Thoughts, things to check or replace, ideas?

 

[Dave_eng]

I Can provide the WSM No Start trouble shooting page.

I have a recollection of someone pointing out that your model does not have glow plugs but rather an intake air heater, i.e. grid heater. Further that this heater was important even in warmer temps.

The wiring diagram shows two "boxes" for slow blow fuses. The intake heater has a 20 amp slow blow fuse. Are these the fuses you are checking or are you just checking automotive size fuses?

Does your tractor have a cab as it makes a difference in the wiring diagram?

I am going to send you a private message. Look for the envelope symbol at top right of most forum pages.
Dave