I had an o-ring fail on the side of the injection pump on my 94 6.5 K2500 Suburban. I found pulling the intake manifold was the easiest way to gain access to the passenger side of the pump to remove the cover and change the o-ring. Got everything back together and started it up. Since that point, I have 2 new issues. I still have a fuel leak, but can't figure out where it is coming from. It drips off the rear of the engine. The valley looks oily, but not particularly fresh - it just turned 200K. Any common points of leakage that aren't so easy to find?

Also, it started knocking. It sounds worst at idle. Oil pressure is just as it was and the noise seems to subside while rolling down the interstate. I swear at times - its gone at idle, but does return. Runs fine and just as smooth as it did before repairing the first leak. Did I get air trapped in the fuel system somewhere to cause the noise?

Any advice would be appreciated. I love this truck and drive it daily. For a 94, its in great shape. I just don't have a ton of time right now to spend tracing the leak and trying various solutions without a general direction.

I'd be tempted to take it to a shop to get it resolved, but my faith in shops is low and where would I find a competent and trustworthy mechanic that knows the 'ol 6.5?

Thanks.