Need help with Deck Height w/ domed pistons
 

I am trying to check deck height with JE 90mm 9.5:1 pistons. I have read the section in Wayne's book regarding deck height. I am using the solder method. I am not clear as to where I am supposed to measure the solder to get the deck height. I believe that in Wayne's book, it states that I am supposed to measure the solder at the thinnest point. My problem is that the thinnest point measured was at point "A" in my picture. I have been told on other posts that I should be measuring the solder at point "B".

I want to make sure that I am accurate for obvious reason. As of my last shim arrangement, I measured point "B" as 1.50mm and point "A" is 0.75mm.

Where is the correct place to measure deck height?

http://forums.pelicanparts.com/uploa...1420927299.jpg

If "A" is the place to check the deck height, then what is the minimum acceptable HEAD to piston clearance? I know that the piston to valve clearance must be 1.5mm intake, 2mm ex.

Squish
 

Dear Tomik,

you have to check both spots.

Your spot B is correctly adjusted at approx 0,8 mm then it should open to spot A to 1,5 mm.

To get it done best possible avoid too much pressure on the bearings, put the solder on both sides of the wrist pin axis and measure spot A and B separately.

A good working squish band is essential and one of the most important things to do on an engine !

Best reg.

Dirk

What you describe is not deck height. Wayne has it wrong in his book. You are measuring head to piston clearance. Deck height is measured from the top of the cylinder to point "B" in your drawing.

Measure deck.
 

I am all ears.

Nice picture - Thanks.

So point A must be.? And point B must be.?

Cheers - Tommy