[Formulajones]

To check and/or make a new mark on the balancer, if you want it to be exact (and it really needs to be)

On an assembled engine you'll need a piston stop that screws into your spark plug hole. Very simple and cheap tool everyone should have in their toolbox.

Insert piston stop. Rotate engine clockwise until #1 piston touches, mark the balancer in this position, for example it may read 20 degrees BTDC.

Now rotate the engine counterclockwise until #1 piston hits the piston stop. Mark this position on your balancer, for example this time it may read 15 degrees ATDC.

What is exactly in the middle of those 2 marks is your new SPOT ON top dead center, which would be 5 degrees BTDC with the example I've given, which would show your balancer was off by 5 degrees.

I do this with every engine, usually during assembly while I am degreeing the camshaft,,,,,as I've had brand new balancers that weren't marked correctly or possibly the keyways are off slightly etc...You just never know with some of this aftermarket stuff. ALWAYS CHECK, cheap insurance and it only takes 5 minutes.