How do I measure ring end gap and Piston to Cylinder clearance

[go high fast]

What is the proper technique and what tools do I need for these measurements? Thanks

 

[NapaMatt]

The Ring and the Cyl.. From the top have end gap up.. Push the ring in to the cyl.. Then push it down in the cyl with the piston so you know its square.. then measure the end gap.. with feeler gauge..

 

[sledhed]

I also measure the ring pushed in from the bottom a little ways just in case there is some taper to the cylinder. As for measuring cylinder diameter vs. piston diameter (difference = clearance) that takes some more specialized tools and techniques, snap gauge and micrometer or bore gauge is the best way if I recall my machinist days correctly (long time ago). I think you can put a piston without rings into the cylinder (from the bottom) and try to put a flexible feeler gauge (of the minimum clearance size) between the cylinder skirt and the cylinder wall to make sure the clearance is good... this would be for new pistons of course. You could then progress to bigger feeler gauges if the clearance seems excessive to find the largest one that will fit.

Carefully of course, to not scratch the pistons / cylinders...

But the right way is bore gauge and micrometer and sample multiple points in the cylinder, high and low, and piston with micrometer. Good ones can run a couple hundred bucks if I recall correctly.

http://www.ebay.com/itm/PRECISION-E...880?pt=LH_DefaultDomain_0&hash=item5670fd44d8
http://www.ebay.com/itm/SHARS-0-100mm-Solid-Metal-Frame-Micrometer-Set-/400867162892?pt=LH_DefaultDomain_0&hash=item5d558b7b0c

Those are just examples, not sure if they would work for you, I think the micrometer set won't go big enough, but it gives you an idea...

Since I don't have those gauges and don't do it often enough to make it worth buying them, that is why I take it in to a dealer and have them run the hone through it and then check my clearances for me...

 

[go high fast]

Will this work?

 

[slash]

no it will not

 

[go high fast]

Are you sure? I've been using that to measure horsepower, torque and air fuel ratio and exhaust gas temperature's. I thought it did everything. Just poking fun at me not you slash.

 

[xc6rider]

I believe that the factory actually uses a caliper to measure piston clearance.

 

[xc6rider]

Back on track..

NapaMatt explained the ring gap process up above! Pretty much all their is to it. You wanna measure right around the point where the rings would be depth wise, at TDC, roughly...

Also, youll need a good set of thin, fine files. If you need to increase gap. And remember, you cant add material back to the ring if you go too big.