piston to valve clearence measuring

[lyonsy]

iam woundering how to measure the pistons to valve clearence on an engine.
thanks

 

[XPC66]

Subsitute with a weak valve spring and measure the stem displacment as you push it down to make contact with the phased piston.

 

[lyonsy]

ahhh ok so basicly up on top dead and compress valve tile ether spring bottoms or valve hits piston
thanks for that

 

[Stubby]

Not exactly. The exhaust will be closest before TDC and the intake will be closest just after TDC. More later.

 

[rbohm]

Not exactly. The exhaust will be closest before TDC and the intake will be closest just after TDC. More later.

8) exactly, and the exhaust valve clearance is the critical one as the piston chases the exhaust valve, where as the intake valve chases the piston. as i recall the critical point is about 20 degrees before top dead center. set the piston at that point on the exhaust stroke, and then using a dial indicator open the exhaust valve further until the valve hits the piston and see how far it travels. if it is at least .100" you are fine.

 

[Gene 64 2dr]

I've read that if you put some soft clay on top of the piston and bolt down the head. Then turn the crank over slowly by hand. The valves will make an impression in the clay that you can then measure.

Gene

 

[fb71]

yup. I use my kids' Play-Doh

 

[Does10s]

Yup! The Play-Doh method works well.

Or some clay from a art & Crafts store.

Just make sure you use the Ford Blue color!

Will

 

[Geezer 300]

And use a solid lifter as the hydraulic can bleed down !!

 

[lyonsy]

thanks for all the usefull info on it very helpful
anther one to the fav tec section