top dead center

[slugish]

forgot to mark my distributer when I removed it for new heads & cam upgrade . What is the best (or simplest way to find top dead center so I can mark my damper . Its already marked , but Iwas told Ihad to find top dead center on the compression stroke & mark it . Was told one way : get a plug stop-put it in # 1 cylinder plug hole --rotate engine clock wise till it hits - mark spot on damper-then rotate counter clockwise till it stops again - mark damper again - measure the distance between the 2 marks - top dead center will be 1/2 way between these 2 marks . How do yall do it

Thx Will

[Keith Seymore]

Yep. That's it.

K

[bigwheel15]

You can pull the number one spark plug, place your thumb over the hole and have a friend bump the key until you hear/feel air from the hole. Place a stiff wire about 8 inches in length in the hole until you feel it touch the top of the piston. Rotate the motor keeping an eye on that wire as it moves out. When the wire stops moving you're now at tdc. Mark you're balancer, drop you're distributor and reinstall you're plug. Done
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[BamaDave]

Dumb question. Mark it where? Where the "0" is on the tab?

[old Rusty C10]

Originally Posted by bigwheel15

You can pull the number one spark plug, place your thumb over the hole and have a friend bump the key until you hear/feel air from the hole. Place a stiff wire about 8 inches in length in the hole until you feel it touch the top of the piston. Rotate the motor keeping an eye on that wire as it moves out. When the wire stops moving you're now at tdc. Mark you're balancer, drop you're distributor and reinstall you're plug. Done
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this is how i do it

[Firebirdjones]

The way slugish described it is the "accurate" way to do it,,,so you find "exactly" where TDC is. This method is more about finding an accurate timing mark in case the balancer has moved (then remark it). (I've seen them out as far as 9 degrees)

Using this method will allow you to set timing properly when engine is running.

[1981Sturgis]

My guess is that he wants to find where the #1 plug wire goes on the dizzy. Therefore I would:
pull the #1 plug,
put thumb over hole,
bump starter untill pressure,
turn engine by hand(same direction) to line up mark on balancer with "0" on timing tab,
pull cap off dizzy,
see where rotor is pointing and mark that spot,
reinstall cap,
find plug wire terminal closest to mark,
align terminal to mark,
install #1 plug wire in that terminal.

This should get you close.

[slugish]

thx everyone for the replies . I still have the intake off where Ican see the valves opening & closing . Is top dead center also when the intake & exhaust valves on the # 1 cylinder are all the way down , or is this not an accurate way of determing tdc .

[2002on22s]

I've always taken #1 spark plug out & put a long wadded up paper towl in the spark plug hole, then bumped the starter w/ the dist unhooked until the paper shot out & there you go... Works in a pinch if you're by youself too

[Keith Seymore]

Originally Posted by slugish

thx everyone for the replies . I still have the intake off where Ican see the valves opening & closing . Is top dead center also when the intake & exhaust valves on the # 1 cylinder are all the way down , or is this not an accurate way of determing tdc .

Originally Posted by 2002on22s

I've always taken #1 spark plug out & put a long wadded up paper towl in the spark plug hole, then bumped the starter w/ the dist unhooked until the paper shot out & there you go... Works in a pinch if you're by youself too

These methods let you know you are in the ballpark, but if you need to know dead on then you have to use the method described in the original post (...or trust the marks on your balancer).

K