Re: Timing question

["Paul C. Waterloo" <74543.407@compuserve.com>]

>After having spent most of the day changing the timing belt and
>water pump on my '91 200tqw, I have a question:

>What is the allowable/acceptable "play" in the rotation of the
>cam gear with respect to the TDC mark on the fly wheel.

>Prior to pulling off the old timing belt, I rotated the engine
>around to TDC: dimple/punch mark on the cam gear directly
>underneath the arrowhead and the flattened "O" from the flywheel
>directly next to the timing mark on the bell housing.  I also
>checked to see what was "reasonable" tension in the belt.

>When I replaced the belt, I left everything where it was and
>reinstalled/tensioned the belt.  I re-checked the timing marks,
>cinched everything in tight, then rotated the engine once.  The
>cam gear was dead bang on, but the "O" was a little off. 

> When I attempted to center the "O" to check how far the cam
>gear would be off with the fly wheel centered, I found I could
>move the "O" above and below the center mark approx 2 - 3 mm
>(1/8 ") without significantly moving the "dot"  away from the
>arrow. "Aha!  Thinks I.  The belt must be too loose.  Timing
>belt lash is what I'm seeing."  I snugged the belt a little
>tighter and repeated.  Same effect.  

Make sure you are always rotating the engine going the same direction, and if
you pass the mark, go all the way around again, not backwards.....otherwise
backlash will come into play.

I found that when I changed my timing belt, I couldn't get everything perfectly
lined up, but I could get the timing belt on the correct tooth of the cam gear.
Because there is no other adjustment, you can't get it right on, just on the
right tooth. Don't worry, nothing will blow up.

Doesn't the crank tool make removing that nut incredibly easy? The job is big
enough without worrying how to get that thing off.

Paul

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Paul Waterloo
Colchester, CT

91 200q

EMAIL: 74543.407@compuserve.com
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