Originally Posted by
AndreasI was speaking to DERM about your problem 12 hours ago and I told him it mostlikely was a TB screw that came out.
That is the worst thing to happen
Yeah I was very puzzled by this problem. I told derm it sounded like something was flying around inside the head/VC for a few minutes, but then it was gone and the valvetrain just sounded very noisy. (like a shim was out of place or something)
Pulled the VC and cams and dropped the lower oil pan and couldn't find anything strange.
This morning I woke up and it hit me - I never checked the TB. Spoke to derm and told him I suspect a TB screw and he told me you said the same thing as well. Went to check and there it was - a gaping hole where the one TB screw is meant to be.
Now, I pulled the head last night and found some marks and stuff, but the loose item (now known to be the TB screw) is no where to be found.
Do you think it got blown past the exhaust valve and out the exhaust?
What bothered me most is the rattling noisy valvetrain, in spite of the screw not being present in the head/cylinder any more.
Started removing the valves this morning just to double check them all and one of the exhaust valves came out almost too easy. I didn't even need to apply a lot of pressure on the valve compression tool. The one cotter pin just popped out. So I'm hoping it was a little bit out of place, causing the noisy valvetrain? It didn't look strange on first inspection after removing the shims.
Here are some pics. Let me know what you think the best course of action is:
scuffing on the head - cyl 2 (I think this is okay?)
indentations on the no 2 piston, on the intake side. Right on the edge against the cylinder wall, but doesn't look like it's interfering with the cylinder wall at all. Just curious if this will create hot spots and detonation perhaps?
interestingly enough, cylinder 3 has some threaded bolt imprints in the head. But it's covered in carbon/fouling/fuel which tells me it was from the previous build!?
Any advice appreciated.