Valve shim clearance

Two of my exhaust valve shims accept my .152 gauge. Should I go one lower which I assume it will raise the clearance to .202? I've been told exhaust valves are better a little loose rather than a little tight. Any thoughts?

Thanks.

 

"Accept" as in JAM it through?

IN spec is in spec; OUT is out. The whole system is designed so that one shim and one shim only will put a particular valve IN SPEC.

You're using Imperial ("American") gauges with metric equivalents. If you want to do it easily/right, use a "primarily" metric feeler, like the K-D 2274, widely available.

For exhaust, .20mm is in spec and .15mm is not. Drop that .002mm. What does .002 MILLIMETERS come out to, anyway?

Assume nothing, but re-shim. And get a metric gauge. You'll sleep better.

 

'Accept' means it goes through smoothly, but only because there's oil all over the cam lobe and shim. And my feeler gauge is both metric and standard.

Thanks for the advice.

 

No, your feeler gauge is "standard" (Imperial) printed with metric equivalents.

I was recommending a purely metric gauge; that is, one whose blades are straight METRIC sizes.

In other words, instead of your .006" blade which is also marked ".152mm" you would be using a metric blade simply marked ".15mm." Which actually measures .15mm, not .006" (or .1524mm.)

Makes the job much easier, honest. Especially when you do it for the umpteenth time. (Every 5K miles.)

You're welcome.

 

So should I re-check with a solely metric gauge before continuing? Or is it obvious that they need changing either way?

 

go with the .202 clearance.

 

Oh, definitely. Drop the .002mm, you're in spec at .20mm.

 

Awesome. Thanks fellas.