tdc how to find on comp stroke

[WE287GN]

and does it matter wich stroke when checking pushrod lentgh

looks like on one strke right before tdc ex opens and closes tdc,then intake opens

wich stroke is that ex??

Thanks
Chris Pacheco

 

[blackbuick87]

If the heads are on just pull the plug and stick you finger over the hole. The air will push your finger off the hole on the compression stroke

 

[Jimn8or]

...above post continued. Obviously it's the #1 spark plug that's pulled here. When you have a buddy bump the engine over with the starter [ECM unplugged] you will feel the air push on your finger that's covering the spark plug hole. Be sure it's blowing and not sucking Then move the engine, from the crank pulley bolt, until the timing mark lines up with TDC. Visually confirm that you can see the top of the piston thru the spark plug hole with a light...you're there.
Jim

 

[Tom87GN]

I was just setting a cam sensor for a buddy last night and his balancer had TWO timing marks cut in it. I think I could tell which one was the original and which was not. Quite confusing, though. I'd never run into that before. A prior owner must have thought he'd be sneaky and try to mess it up for the next guy.

 

[WE287GN]

Originally posted by Tom87GN
I was just setting a cam sensor for a buddy last night and his balancer had TWO timing marks cut in it. I think I could tell which one was the original and which was not. Quite confusing, though. I'd never run into that before. A prior owner must have thought he'd be sneaky and try to mess it up for the next guy.

wonder if that second line isnt is atdc # and was cut in to make setting cam easier

are those two marks apx 1.5" away from eachother original to the left?

Chris Pacheco

 

[WE287GN]

ok i have the pushrods out ,dont think nlow suck is going to tell me tdc compresion stroke or exhaust??am i wrong?

i am watching the movements of ex/in lifter s on the particular cylinder i am trying to check my pushrod length for

i was hoping to define the valve actions just prior and after the ex and compresion strokes


do i even need to have it on comp or ex to measure pushrod,does it matter???

Thanks
Chris Pacheco

P.S. this other stuff good to know since i will be putting my cam sensor back in soon

 

[Tom87GN]

Chris, I measured off a piece of tape the 1.45" that it calls for and the other mark cut in the balancer was about 1/4" from where it should be. That's what was pretty confusing to me. I thought the same thing you did, that is was 25* ATDC.