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George H.
George H., ASE Certified Technician
Category: GM
Satisfied Customers: 18390
Experience:  15+years ASE Master W/L1 Drivability
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when timing a 350 chevy engine #1 piston is on compression

Resolved Question:

when timing a 350 chevy engine #1 piston is on compression stroke top dead center what is the position of the valves so maybe i won't have to take every thing back off the front of the engine.
thanks joe
Submitted: 7 years ago.
Category: GM
Expert:  George H. replied 7 years ago.

Hello I will help you with your question,


If you are concerned with the camshaft position relative to the crankshaft it is very hard to determine position without a dial indicator.


The intake and exhaust valves are closed with the crank at #1 TDC so there is a large window that the cam can be in while the valves are on the base circle of the cam.


Tell me what you are doing and what Year this engine is and I may be able to provide further information for you


Thank you



Customer: replied 7 years ago.

where will the distributor rotory be pointing also how do i make sure i am in time with that large window you spoke about and make sure i am top dead center on compression stroke. im not trying to be a problem but i put this together my self had every thing in time i thought. then when it did not start and back fired instead of turning the distributor a little i took the distributor out second guessing my self then i remembered i may have gotten off before i may have taken the distributor out i cant remember. i only get to work on this every 2 or 3 months because i work offshore.





Expert:  George H. replied 7 years ago.

I'm going to guess that this is a 1986? from your signature


Ok to install the distributor, rotate the engine until the timing mark is at TDC on the timing pointer.




If it starts at all the rotor should be pointing to the dark circle on the distributor cap which is #1, if it is pointing to #6 turn the crankshaft one complete revolution as you are on TDC exhaust #1




If the plug wires are routed correctly this should get it started then you can worry about exact timing.


Let me know if I gussed wrong on the year as they do change

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