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Puckdou
06-26-2020, 06:09
I have recently acquired a 1999 Chevrolet K2500 automatic and a 6.5 Diesel engine. The truck starts fine when it is cold. However, once the engine comes to normal operating temperature, the truck will not restart. After the truck has completely cooled off, it starts easily. Any suggestions on where to start looking for a problem?

Known:
1999 Chevrolet K2500 6.5 Diesel
Mileage: 212,000
Injection Pump = Replaced with new OEM pump less than 100 miles on it.
PMD = New and a known working spare
Stater = New OEM
Batteries = New 850 CCA
Fuel Filer = New
There is engine blowby

rnash4
07-20-2020, 19:42
Pukdou, I don't mean to insult your intelligence, but when you said you replaced the injection pump (top of engine) just making sure you're not confusing it with the lift pump on the frame rail under the driver's seat?

High Toned SOB
08-11-2020, 09:30
So aside from what was said above, if you have not replaced the ip and its wore out (by what you describe) then you have a couple options.

1. Replace it

2. Up your supply pressure. On my old 98, it had over 200k on it, and it was having a hard time starting when hot (basically a 20-60 minute window after shutdown). So i turned my liftpump from 6 up to about 16 psi and it was good. It may have been a little higher, but my gauge maxed out at 15. No adverse affects, drove it fro probably another 10k miles with no issues then trades it off.

High Toned SOB
08-11-2020, 09:32
Oh also every 6.2/6.5 i have ever had has blowby. Once it starts “puffing” then your in trouble, haha

High Toned SOB
08-15-2020, 17:37
Any updates?

cadillac_diesel350
08-30-2020, 18:41
This problem is probably solved by now but usually those symptoms point to a bad pmd among other things but sometimes it could be a bad remote pmd harness if you have it relocated.The quality of those can be poor depending upon who you buy it from.If the pmd isn’t relocated you should do it anyway to prevent future problems when the engine is hot.