Vehicles are frustrating...

[mike31154]

Originally Posted by hillegom

Mike, is it just an O ring you need? You can't take out the old and get a new viton O ring the same size?
Whats involved with a whole kit? different size O rings?

The kit includes most of the seals required to do a pump overhaul. While I don't need them all, I thought I may as well try to get a kit to replace as many as I can replace myself since I have the pump off the engine. Other than the faulty o-ring, the pump was working fine, so a complete overhaul is probably not needed. Diesel pumps are a little out of my league to get into the innards, but I'll change out as many of the outer seals as I can before putting it back on. The seal on the top cover & the one on the opposite side as the broken one could have been replaced without pulling the pump, which would have got me through the winter & saved me from buying a new truck!

Here's the pump with the offending seal, which is inaccessible in situ since it's right up against the engine block. The o-ring was hard, completely flat & came out in two pieces.





This is the one on the other side of the pump. Same size & it was not leaking, but showed signs of cracking & imminent failure. Would not have lasted too much longer either. This one I could replace with pump on the engine.



Apparently the new low sulphur diesel fuel they sell us these days contributes to accelerated failure of older diesel injection pump seals.