Finding TDC (top dead center)

[jpian0923]

Finding top dead center, (TDC) with the head off.
The larger of the two valves associated with each piston is the intake valve. Concentrate on that one.
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Finding Top dead center (TDC) with the head on. Maybe not a top quality production video but hopefully the point is made enough to understand how to find TDC with the head on.

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[romantic comedy]

The piston comes to TDC every time, exhaust and intake strokes.

Mostly TDC is needed to make a mark for checking and setting timing. I use a method where a dial indicator is used.

The crank is turned till the piston is that the top. The indicator is set up and shows the highest point of travel. Then the crank is turned a few degrees until the piston is lower in the bore just a little. A mark is made on the pulley. Then the crank is rotated in the other direction, until the piston has come to the exact point of downward travel. Another mark is made on the pulley.

TDC is found by making a mark exactly half way in between the two marks.

[Dave Neptune]

Tdc

Hey Romantic, very nice explanation of finding TDC.
If you split the results of doing both of the pistons at the top you can also see how close the crank throw's C/L's are too.

For timing purposes TDC is during the compression stroke, usually done with #1 cylinder. If it is difficult to access you can use any cylinder for the same timing purposes, just use THAT cylinders TDC compression stroke.

Dave Neptune

[quiesence65]

Found TDC!!!

Somehow my timing was thrown completely out of whack when my rotor was somehow broken.....I spent a couple of days trying to find TDC until I found this video on the net! Went out, found TDC, replaced my rotor and SP wires, and away she went. Thank you...thank you...thank you!

[jpian0923]

Cool. Glad it was helpful!