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[Kevin Wood]

I'd say if the collet has come out, it's probably because there was valve to piston contact and it shocked it out of the groove in the valve stem. Not sure how it ended up there but I suspect you may have some damage that needs to be investigated. You could have other bits loose which will do more damage :-/

I think, unfortunately, the heads may have to come off.

If you need more justification, try a compression test.

Kevin

[Don9247]

im just trying to figure out why and what caused the problem seeing as my timing was correctly setup what would have suddenly caused the engine to break at tick over, and the engine still runs just now with a knocking noise,
The valve lenght is 92mm according to haynes and the bore stroke is only 86 mm so the valve will never actually fall into the piston chamber but it is continually ontop off the piston being pushed up and down through each and obviously when the engine is running the piston is hitting the valve up quicker than it can fall down, i think that why the noise can be heard wth the ebgine running but when you just turn the engine over with no spark plugs in it doesnt knock because the engine is still spinning slow enough for the valve to just rest on it during the stroke.

[Mike Collins]

If the valve is no longer retained and is being moved by the piston, you have no choice but to remove the head, that valve stem is almost certainly bent.

Do I recall earlier in the thread you said the timing was found a few teeth out?

[Kevin Wood]

The valves are at a suitably acute angle with respect to the cylinder that they'll get chewed up rather than just bob up and down on top of the piston.

If the cams were out by 2 or 3 teeth in the wrong direction that may have been enough. Maybe the collet just failed :-/

I'd do a compression test, just to verify that you do have something seriously wrong. I suspect you'll find a cylinder with no compression if so, and you'll know it needs to come apart.

Bear in mind that the lifters are often noisy after a cam belt change, and take a little while to quieten down. Your noises sound more serious than this, though.

Kevin

[Don9247]

FOUND THE EFFFIN CULPRIT
on th middle cylinder on the righ bank on the two inlet valve the ends of the valve guides have snapped off also only one valve has bent my piston has some squished metal marks NO SCORING WAHOOO
and so does the head have some squish marks.

Now heres the question how do i get the two valve guides out? and the two new ones in.?

Many Thanks Don

[Kevin Wood]

Now heres the question how do i get the two valve guides out? and the two new ones in.?

I would have thought it'd need a press. I've always taken heads to an engine specialist for this type of surgery.

So, the piece in the plenum was a bit of valve guide? Makes a bit more sense. I'd give the rest of that engine a very careful check, obviously. What's happened to one cylinder may have happened to the others.

Any evidence of what caused it? Was the cam belt or one of the tensioners damaged? Are there any witness marks on the other pistons to indicate contact with the valves?

Kevin

[Don9247]

Every other piston and valve is fine, had the valves out now 1 is bent the othr is fine the are both inlet and both the bottoms of the guides have come off , now my theoy is this engina had a cambelt go onit at some point and some has replaced it and change the head gasket and what not as it all looks clean I suspect they just changed the bent valves and not the guides. now the valve guide has after a few thousand miles has acutually broken from the damage caused in the past.

well theroy anyway as belt and tesioners are fine.

Head is now in machine shop getting the old valves out and new ones in also having the others checekd and replacing anything that needs to be. so monday get my head back now i have to find the time to fit it.!

Hw do i add images?

[Kevin Wood]

I guess so. If one inlet valve was damaged without the other (since they open together) it was probably wedged open by a bit of debris, got lumped by the piston and the debris then flew up into the plenum.

Good to know it's salvageable with a little work though.

kevin

[Don9247]

Its my baby I have to fix it lol !