What is piston ring end clearance ?

[hobieboy]

The spec book specifies (among other things) this clearance. It is measured pretty much at the "level" where the cylinder meets the crankcase.

Thanks...

P.S. I think Piston Ring Side Clearance = gap between ring land & rings?

[Eagledriver]

You are correct about the side clearance. The ring end gap is the "hole" that is left between the ends of the ring when it is in the cylinder bore. It is measured with a feeler guage. The ring must be square in the cylinder to get an accurate reading. I put the rings in near the top of the cylinder where the maximum wear is to see if the rings are still in spec. If you are using new rings then you should check them further down to make sure they are not too tight where the cylinder is not as worn.

-Andy

[hobieboy]

Hi Andy, thanks for the response.

A few more questions just to be sure: Do you put the ring in without the pistons? And it is the gap between the hole in the ring after its compressed & put inside the cylinder?

Thanks...

[DonE]

Place the ring in the cylinder without the piston. Take the piston, using the top, and push the ring into the cylider to the depth you want, then measure the end clearance (gap).

[euro911sc]

Use lube/oil to make things slide easily?
-Michael

[cstreit]

Yep...

[hobieboy]

Thanks for the explanation folks...

[Eagledriver]

using the piston to push the ring in may not work if your piston has a funny dome like the CIS pistons. The dome will push the ring crooked and give a false reading.

-Andy

[DonE]

Since he has a 930, this shouldn't be a problem. However, you are correct otherwise.