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RE: Need info on cam timing, 91 325ix



In a message dated 11/12/1998 8:15:06 PM Eastern Standard Time, owner-bmw-
digest@domain.elided writes:

<< I'm in the process of replacing the timing belt on my 91 325ix
 and I have a few questions for people who have done it.  I have 
 everything off the front of the engine except the timing belt, 
 and when I line up the  O|T  mark on the vibration damper with 
 the mark on the belt cover, the cam sprocket mark does not line 
 up with the mark on the head. (confirmed that piston #1 was up 
 on compression stroke) The cam sprocket is advanced one notch.  
 How would this effect how the engine runs?  It did seem to run 
 pretty good set up like this but I have nothing compare it to.  
 (only e30, m20 engine car I've ever driven)  It appears that the
 shop that installed the last timing belt, did it wrong.  I didn't 
 own the car at that time.
  >>

I just replaced the belt on my 89 325i (a little different I'll admit) and I
noticed that when the belt is loose (my old one was very loose), you can have
the belt on properly and get the marks to misalign if you rotate the crank
slightly backwards.  Make sure you are rotating the crank in the direction of
engine rotation (the crank gear will pull on the part of the belt that goes
directly to the cam gear and not over the tensioner and idler pulley).   If
you do it this way the old one may line up.  Or, the old one may be on wrong
because the last mechanic screwed it up.  After you get the new one on, make
sure you rotate the crank in the correct direction a couple of times and
recheck the marks.  Also, the tensioner should be reset after the rotation.
Whatever you do, don't rotate the shafts independently or the valves will hit
the pistons.

Also, for what it is worth, all I had to remove to get my belt on was the
pulley balancer which were held on by a series of 13mm bolts.  Hub removal was
not required on my engine.

Gregg  (Humbly providing my advice which may not be the best)

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