# How do you find Top Dead Center



## vw-4-me (Mar 7, 2001)

This is my dilema
I am installing a used engine 2.OL engine into my Jetta III. How do I align the timing marks to install the distributor and transmission. I just need instal my distributor and transmission to complete.
Thanks in advance.


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## Just Some Guy1 (Jan 7, 2002)

*Re: How do you find Top Dead Center (vw-4-me)*

There is a notch on the front crank pulley and an arrow on the black plastic timing cover that you line up.


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## vw-4-me (Mar 7, 2001)

*Re: How do you find Top Dead Center (Just Some Guy1)*

Yea but that usually involves aligning the flywheel up to ensure you are on the right compression stroke.


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## speed51133 (Feb 18, 2000)

*Re: How do you find Top Dead Center (vw-4-me)*

take out a spark plug. put a long screwdriver in the hole. turn the crank by hand with a 3/4in 12pt socket on the crank pulley. TDC is when the screw driver is at its highest point on the COMPRESSION stroke. you can determine compression stroke by going through all the strokes with all the spark plugs taken out, and just leave the #1 piston plug in. Compression is when its alot harder to turn the crank. When that happens, take out the last plug, and put the screw driver in. TDC is when it is at its peak.


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## bajan01 (Nov 26, 2001)

*Re: How do you find Top Dead Center (speed51133)*

When I was playing around with single cylinder motorcycle motors I used the screwdriver method all the time and loved it as the timing marks never seemed to line up just right. Things are much easier with a single cylinder but as you are just messing with cylinder #1 then the method should work just the same. To check that I was on the compression stroke and not the exhaust stroke, I would feel or listen for the air rushing out of the spark plug hole. This is most noticeable on the compression stroke as all of the valves are closed and the only place for the air to go is out the spark plug hole. This gives the same result as leaving in the spark plug and feeling for the pressure in the cylinder. Good luck


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## Just Some Guy1 (Jan 7, 2002)

*Re: How do you find Top Dead Center (vw-4-me)*

I think you guys are missing the that if the CRANK pulley mark is lined up, the #1 piston is at TDC, period. There is NO difference between TDC exhaust or compression on the CRANK-whether the #1 piston being at TDC is an exhaust or compression stroke is dictated solely by the position of the CAMSHAFT.
The cam must then be lined up with its own marks once the crank is properly positioned (assuming the timing was off or he had the timing belt removed). When the crank pulley is lined up with its mark, and the cam pulley is lined up with its own mark, that is TDC #1 on the compression stroke, period.


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## speed51133 (Feb 18, 2000)

*Re: How do you find Top Dead Center (Just Some Guy1)*

what if you just assembled the motor and your unsure if the cam gaer and flywheel are on correctly?
my method i stated is fool proof.


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## spitpilot (Feb 14, 2000)

*Re: How do you find Top Dead Center (speed51133)*

Cam gear, crank gear/pulley, intermediate shaft gear, and flywheel all have indexing so they only go on in the correct positions. Line up all the timing marks per the above posts and you should be good to go. Only one not mentioned above is to have distributor rotor pointing at #1 notch in dist. body when the crank and cam marks are lined up. Then cam and ignition timing should be on the money. http://****************.com/smile/emthup.gif


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## vw-4-me (Mar 7, 2001)

*Re: How do you find Top Dead Center (Just Some Guy1)*

What mark are you talking about on the crank pulley?
My distributor is removed along with the transmission so i don't have these marks to align. Hence my problem on how to install these items timed all correctly


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## EleCTriCT_ (Jun 13, 2002)

*Re: How do you find Top Dead Center (vw-4-me)*

Take top timing cover off use 19mm 12pt. socket to crank engine clockwise
turn until OT mark on cam sproket is lined up with OT mark on the plastic cover behind it. Then make sure the crank sproket mark is lined up with the mark on the lower cover. This is TDC you can verify piston tdc if the tranny is bolted on , the "0" on the flywheel will line up with the pointer in the hole where the green plug should be
then you can plop the distributor in making sure the center of the rotor lines up with the mark on the housing, also making sure that bolt hole for the lock lines up in between the 2 pins


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