So chasing down long crank and rougher idle on sons 99 SD (Lil Foot).
Low ICP....Replaced ICP, better but not fixed
Low IPR at crank...Replaced IPR, no change
Talked to friend he said injector o-rings, or maybe LPOP, but most likely O-rings
Ordered up o-rings, hpop reservoir gaskets, and LPOP from RiffRaff.

Replaced 'the LPOP, no scoring. Gears had a little wear, 228k miles.

Started pulling covers and working on injectors.

This is what we found.





These are the worst. 7 of 8 were damaged.



All o-rings replaced. Life is grand. Ran out of time to finish up, we'll wrap up tomorrow. Got to spend the day with my son (21) doesn't happen very often any more.

Also injectors only have 24k miles on them. Going to contact the vendor.

Happy Easter all.

Keith & Craig

 

Reps to you for not naming the vendor without giving them a chance to make it right

 

So is it poor quality orings or could they have been damaged during the last installation? At 165K I know my day is coming and I've been trying to study all I can about oring replacement.

 

Bigb56
Download the inector o ring tech sheet from RiffRaff. It's very comprehensive. I took the alternator off out of convenience. It's not as imposing as it looks. Make sure you have or get a minivac or some kind of vacuum to evacuate the cylinders.
Let me know if you have any questions.
Keith

 

One of the forum's favorite vendors had a bad batch of O-rings about 2 years back. It happens.

 

At this point in time I don't remember exactly how they normally fit, but it looks like the steel backer ring is too small and the gap is allowing the square cut seal and o ring to flex until they blow out at that point.