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how to get cam timing correct  Rate Topic 
 Posted: 04-09-2011 10:30 pm
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Joined: 07-06-2010
Location: Mariposa, California USA
Posts: 19
I was replacing my timing belt and thought thought I was done with it. I had the engine at 90 deg after TDC while replacing the belt. I began to turn the engine by hand, and the belt slipped because the tensioner was not tight enough. I stopped turning, but don't know if one or both cams turned too. Is there a way to get it lined up again?

Is there a way to get it close enough by counting teeth or something so I can turn the engine to TDC without killing the valves? Do I have to pull the belt and cam covers and rotate the cams to a position where they should be for TDC timing, then rotate the crankshaft back to TDC and re-install the belt?

Thanks for any advice,
Bob Waterman
JH 19695

Last edited on 04-10-2011 12:36 am by h2oman

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 Posted: 04-10-2011 01:32 am
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Joined: 03-20-2009
Location: Colorado USA
Posts: 183
No doubt someone can tell you in more detail what needs to be done, but If I were up the proverbial creek without a paddle, I would:

Remove the belt and set the cams so that all valves are closed, i.e. let the cams go to the position to which they naturally want go to (hold on so the valves don't slam the head).

Set the crank so that No. 1 piston is at TDC (the timing pointer on the crank sprocket will point to the 0 degree mark).   Set the two cam sprockets so that the timing marks line up.  Rotate the distributor pulley so the rotor points to Cyl. No. 1

Install the belt and tension.

You may need to fine-tune the distributor so that the rotor points to No. 1 cylinder.  You will time the engine correctly later; it will run at 0 degrees.

My guess is that you didn't bend any valves when the belt slipped.  The valves would have wanted to go to a more closed position (less total spring tension).  The danger from a scenario when the engine is running, of course, is the next revolution of the engine -- not the initial slip.

Hope this helps,


Last edited on 04-10-2011 01:33 am by Dakota123

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