Using feeler gauges

[rcepluch]

I just checked my feeler gauges and the smallest size was .0015".  This represents approximately .038mm and it is thinner than a sheet of paper.

I am wondering how you use these things when ckecking valve clearances.  These feeler gauges are so thin and fragile it seems that they would  just crumple up when you try to push them under the cams?

Any advice?  Thanks.


Bob

[Kerry]

It's OK for that thin feeler gauge to "bow" when you try it.  Just don't be so aggressive that you bend it!

The nice thing about such a thin blade is that it can teach you how much force to use with the thicker blades.  With the .0015 you CAN'T force the bucket away from the cam lobe just by pushing harder.  If the clearance is barely over .0015 the blade will (slowly) slide in the opening with just a bit of pressure.  Once you've had that experience you will know approximately how hard to push on the thicker blades.

If that blade WON'T fit between the shim and the cam lobe there's one more test to do before you start buying thinner shims.  See if you can spin the shim inside the bucket by hand.  Easier yet, see if you can spin the bucket itself by hand.  If you can do either of these, you have SOME clearance - probably enough to get away with for now.

Make sense?

[rcepluch]

Thanks for the advice Kerry.  That is very concise information, exactly what I was looking for.  I was hoping you could help me out.  Your tips will help provide me the confidence to try and check my valve clearances.

I checked on line for metric feeler gauges and the only set I have found so far, with .03-08mm sizes, comes from England.  They were 10-11 pounds, but I don't know what shipping and other import charges would be.

Well, thanks again Kerry.  Have a good evening.


Bob