Getting Ready To Pull My Motor... Tdc Question.


Founding Member
Jun 16, 2002
Danbury, CT
I broke a head gasket between the #6 & #7 cylinders, causing a misfire and before i knew what the problem was, i revved the motor and (only at high rpms) i could hear a loud clacking noise from what seemed like it was inside the motor. At that time, i assumed i broke an internal part like a rod or something, but i was able to drive the car a short distance home and pulled the heads, which is when i found that i broke the head gasket. Now, im worried that the clacking noise is still a broken part down below, so i dont want to just throw new gaskets on it and assemble it, for fear of grenading the motor. With the heads off, the cylinder walls and pistons look fine, other than some carbon build-up. With the distributor in the motor, i turned the crank with a socket to see the pistons go up and down. i turned it enough for the TDC piston to go from top to bottom and back to the top, twice. I was worried that i need to keep the engine rotation in line with the distributor, but now i want to pull the motor and have someone inspect it, and rebuild it if necessary. so im not sure if that matters? If the engine rotates seperate from the distributor, what will i need to do to get it back in sync? should i turn the motor until a specific piston is at TDC before removing the dizzy? sorry for the long post and thanks for any advice!
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You'll be fine. When you put the motor back together you just bring the number one cylinder to top dead center then stab the distributor with the rotor pointed to number one.
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Finding the compression stroke is fairly easy. Some people use the tissue method: lightly push a piece into #1 hole & rotate engine to the point where the tissue blows out of the hole. That'll be the compression stroke & set the distributor where the rotor points to #1. If i can't tell: I stab the distributor, knowing that if it doesn't fire or runs poorly, all i do is re-stab it 180 degrees from where it is & know that I missed the compression stroke the 1st time.... ;)
But does it matter if its a compression stroke or an exhaust stroke? Without the heads on I can't tell which is which.

The distributor is going to have to come out to rebuild the engine anyway. When you get it back together, stab it on #1 TDC on the compression stroke.

Stabbing the distributor is intimidating until you actually do it for the first time. Then you'll wonder why you were getting so worked up about it?