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View Full Version : Ticking from M20 after head gasket replacement



myles
05-26-2008, 12:49 PM
I've got a reasonably loud ticking coming from the top end of the engine since getting the head skimmed and replacing the head gasket. I've check the valve gaps and they are all ok and its not an exhaust leak either. Its much louder when the engine is not at or near idle.

Does anyone have any idea what I should be looking for? I've started to think it might be a sticking valve, but I hope its not.

E34-520iSE
05-26-2008, 09:17 PM
Does the tick get quieter as the engine warms up? Is the valve timing spot on? These M20 valves are really tricky to set - even mine tick a little bit when the engine is cold. I would go round all the valves again, like Bob says, listening to them and finding out which ones are running slack.

HTH,

Shaun M

alex 1993 525i auto
05-26-2008, 10:25 PM
Did you install a thicker gasket, like stated in a recent post?

http://www.bimmernut.com/forum/showthread.php?t=38456

Blitzkrieg Bob
05-27-2008, 12:39 AM
Adjust the valves

Blitzkrieg Bob
05-27-2008, 12:49 AM
If after adjusting the valves a few times it still ticks.

Try looking at the ecentrics to see if they have a flat spot worn into them.

myles
05-27-2008, 12:45 PM
Thanks for all of your suggestions. I measured the thickness of the head before putting it on and it was 124.97mm, so just bigger than minimum (124.9) thickness and so should not need the thicker headgasket.

The noise does decrease when the engine warms up, but doesn't go away. I will have a closer look at the valve gaps, the eccentrics and the cam timing when I get a chance.

If I can't find any other fix for it I guess I will pull the head off (3rd time lucky) and check for any signs of physical contact inside and work from there.