Quote:
Originally Posted by Jamesp
If it were me, first thing I would do is slowly and carefully turn the engine clockwise to zero timing and lock it. Now you've unloaded the valve spring tension from trying to rotate the cams. Chances are good you won't lose valve timing, and you need the engine at TDC in any case. I would not remove a tensioner before rotating the engine, you want chain tension to keep from losing timing. The pickle you are in now is losing timing by rotating the engine (my engine ran at low RPM for two blocks with a failed IMSB before it was turned off and did not lose timing) or loosening the chain tension to try and center the IMSB bolt, which might allow the valve springs to rotate the cams. I have first hand knowledge that the cams can rotate in spectacular fashion due to valve spring tension (one of many mistakes I've personally made during engine re-assembly). The other thing that is going on is the IMS shaft is supported by a journal bearing at the other end, and the geometry of that bearing is none too happy with the loads currently being imparted on it. That's my 2 cents, with luck others will chime in with their respective experiences.
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Thanks for your detailed help,
i did remove both tensioners at the back first,something made a click noise inside the engine,i think it is the cam moved because of the valve springs,still i am afraid to turn the crank to lock the engine at TDC,i removed the rubber covers of the valves and it looks like the timing is lost now
