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-   -   timing marks on 928s (http://forums.pelicanparts.com/showthread.php?t=525043)

mitsy 02-05-2010 11:48 AM

timing marks on 928s
 
hi could anyone tell me or show me where the timing marks are on the cams im just about to get the belt off but cant seem to see any definite marks thanks:confused:

76FJ55 02-05-2010 02:45 PM

there should be a small notch in the back side of the cam sprocket. It should line up with the notch in the rear timing belt cover for each cam gear. it is possible that you need to rotat the crank an additional 360 degrees to see them, as the cams will only rotate 180. if there are no notches visible turn the crank 360 and check again as they are most likely at the bottom of the cam gears. Also if you have a Euro S or a 4 valve you should have the crank at the 45 degree mark when removing the belt so that if one of the cams spins on you it won't cause piston/valve contact. I'll see if I can find a pic and post it as a reference.

76FJ55 02-05-2010 02:49 PM

Here is a pic borrowed from a rennlist post. Hope the original poster doesn't mind.

http://forums.rennlist.com/rennforum...ce-video-2.jpg

mitsy 02-05-2010 02:49 PM

its a 4.7 euro s 83 so should the cams be held while taking the belt off

morriss 02-05-2010 07:42 PM

Quote:

Originally Posted by 76FJ55 (Post 5167992)
there should be a small notch in the back side of the cam sprocket. It should line up with the notch in the rear timing belt cover for each cam gear. it is possible that you need to rotat the crank an additional 360 degrees to see them, as the cams will only rotate 180. if there are no notches visible turn the crank 360 and check again as they are most likely at the bottom of the cam gears. Also if you have a Euro S or a 4 valve you should have the crank at the 45 degree mark when removing the belt so that if one of the cams spins on you it won't cause piston/valve contact. I'll see if I can find a pic and post it as a reference.

I thought this applied to the 32 valves. Don't you line up the 16 valves at TDC before removing the belt?

MPDano 02-05-2010 08:04 PM

Quote:

Originally Posted by morriss (Post 5168610)
I thought this applied to the 32 valves. Don't you line up the 16 valves at TDC before removing the belt?

It makes it a lot easier to get the new timing belt on correct when you do it this way, but not necessary. We're non-interference.

mitsy 02-06-2010 12:56 AM

non interference does that mean the valves and pistons dont hit each other if the belt snaps

harborman 02-06-2010 07:16 AM

Quote:

Originally Posted by mitsy (Post 5167557)
hi could anyone tell me or show me where the timing marks are on the cams im just about to get the belt off but cant seem to see any definite marks thanks:confused:

You might find this of some interest.

928 S4 Service - Timing Belt

mitsy 02-06-2010 09:45 AM

very much appreciated all thank you


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