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HybridZ

am i one tooth off?


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Okay so my oil pump shaft is at 11:30 and when Its at a really rough idle It's set at 15* BTDC, however in order to do that I had to fully advance the distributor (dizzy screws fully clockwise position). I advanced it even more after taking off the cap screws and moving it but it didn't seem to change anything. But with the dizzy screws set in the middle position, the crank marking would read about 20* btdc, am I one tooth off on the shaft?

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Are you able to run the engine down to 750rpms to check timing and also have the throttle switch on the tps in the on position?

 

If you're higher than that or the switch is off, you won't be able to set base timing.

 

Now I'm pretty sure the pcm only advances timing if the switch is off or the rpms are too high so, if you cannot get 15 degrees with the screws in the middle (or close) then you are one tooth off.

 

Are you sure the balancer rubber hasn't slipped causing the timing mark to show tdc when it is not actually there?

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So I found this picture of the engine before I put the head on, after I took the crank off

 

Photo-0585.jpg

 

Notice the notch position? I have the piston at TDC but not so much calibrated with the notch, its reading what looks like around 9 (+/- 1) degrees advanced? What do you think? Could this cause some pretty terribly low idling and non-runability?

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Proper timing when the timing chain cover is off is the only for sure way. #1 at TDC setting on 0 on the cam timing marks. Then the chain has two shiny links. One to match the indent on the crank gear (there is a small dot ) and same on the cam gear. With the valves closed on #1 cyl, they shiny link will match the position with the indent there.

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well considering the engine is already in the car, the radiator, IC and everything else, i've matched the lobes (at 10 and 2) with a dark visual of the cylinder that's the best I can do. But this picture seems to say that I'm about 9* to many so my 15* BTDC is actually just around 6* BTDC....would that cause my problems?

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