[Tom M]

To find TDC on my new ford crate engine, we took out the #1 spark plug, I placed my finger over the hole while my helper turned the crank. When air came out, we knew we had the compression stroke. Then I put a screwdriver in while he continued to turn the crank. When the screwdriver stopped and started going down, we knew we had TDC.

Then today I saw this on MotorWeek:
http://www.ipatools.com/7882.html
http://www.ipatools.com/7880.html

It's not something you would use everyday or even twice, but it is one of those tools that no one else has.

Tom M.

 

[FFR5163]

Both are very interesting looking gadgets, but I use the Mk-1 finger method!

 

[Mr. Barry]

You can make your own TDC tool out of an old spark
plug...break out the ceramic and tip, and drill and tap the center for a 5/16 thread...then use a long bolt through the tapped hole, with a locking nut at the top...Screw the former spark plug into #1 , get it near top and screw in the bolt (very carefully)...hand rotating until the bolt just barely makes contact..go back and forth until it barely touches in both directions. Voila...TDC!