I'm in the middle of tightening some exhaust manifold bolts and oil pan bolts...leaks everywhere. Pulled the nightmare plug (passenger side back) and the thing has carbon buildup thick as can be. 1000 miles on the plug see photo.

Diagnosis please..suggestions?

Thanks!!!

Marty

Dud injector, weak spark to that plug, and blow-by in that cyl. come to mind. Id check to see that that inkector isnt leaking excess fuel.

Aside from the leaks, are you having oil consumption issues or any running issues? It sure looks like a ton of oil is getting in that cylinder, by the rings, down the valve guides, or even a head gasket.

Just took off the locks on the stage 8 bolts...the bolts were finger tight..hence the exhaust leak. Injectors are new Accel 24lb.

The engine has 1000 miles with new tfs heads and a Felpro head gasket.

I'll ask the mechanic who did the install about the possibility of other loose bolts while I chew his a** about the ones I've already found. I gave him 4 months to install the engine before I started to pressure him. Guess I caused him to rush....


Am I mad........

Weak spark could be an issue...I had an MSD plug start to burn on the headers....wrapped some electrical tape around it and called it good!?!?!?!

The plug next to it is fine.....even though I think the BOSCH plugs aren't going to stay in there long.

#8 is the most commonly fouled plug in any SBC. That corner of the engine tens to sit the lowest, thus that hole has the most oil pooled over the valves, thus it tends to get teh worst of valve seal problems, and thus that plug tends to take a beating if you don't do alot of hard running to keep it clean.

Could also be something else, but i didn't see anybody else mention this so i thought i'd throw it out there.

is there any fouling on the rest of the plugs, even if it's not as bad as 8? you might need to move up a heat range. whatever you do, get rid of the +4s, they are absolute garbage