Valve clearance check using brass feeler gauge | GTAMotorcycle.com

Valve clearance check using brass feeler gauge

robmack

robmack

Well-known member
Hi,

I am going to check valve clearances on my BMW (shim-in-bucket). I have a feeler gauge set that has both brass and steel leaves. I just wanted to know if there are any concerns using the brass leaves instead of steel. Or is my choice arbitrary?
 
Never heard of anyone using brass - didn't even know they existed. Having said that, does it matter which is used? Probably not.
 
Brass feeler gauges are for setting ignition pick up coil gap, the pick up is magnetized and the brass feeler gauge wont be stick to the pick up.
 
Why not use steel if you have both? Either will work, but the brass will wear more than the steel.
 
Brass is softer than steel so it will compress more and may be slightly less accurate.
 
RonnieRev said:
Brass feeler gauges are for setting ignition pick up coil gap, the pick up is magnetized and the brass feeler gauge wont be stick to the pick up.
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I knew about the intended use of brass feeler gauges but just wondered if they were strictly limited to that one use. I am toying with the idea of removing the four brass blades from my set and making individual coloured handles so that I had a special purpose tool for the job. It would make valve checking less prone to errors. I got this idea from a web site.

GreyGhost said:
Why not use steel if you have both? Either will work, but the brass will wear more than the steel.
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RetroGrouch said:
Brass is softer than steel so it will compress more and may be slightly less accurate.
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Of course, I could use the steel ones. My question came out of my curiosity. When checking the valves on the BMW, it's pretty much Go-NoGo. I'll be checking for a loose fit on .15mm and no fit on .20mm for intake; loose fit on .25mm no fit on .30mm for exhaust. Probably will be no wear at all on any feeler blade since none will exhibit drag.
 
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Brass, being very soft, has the possibility of peeling if it jams against something. This has the possibility of leaving fragments behind. I wouldn't use them.
 
Gages aside consider these two easy to make tools that simplified the job for me. First was little more than a fat brass screwdriver that was easy to wedge between lobe and shim to compress the spring. Then the second was a ground down very large open end wrench ( I think I started with a thin wrench for tightening the blades on a hand grinder) This one would fit the cam shaft (not lobe) with the bottom edge catching the edge of the bucket to hold it down while you fish out the shim with a magnet. Worked mint.
 
dirtbag said:
Gages aside consider these two easy to make tools that simplified the job for me. ...
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Good tip. There is a guy in the States that makes and sells these two tools for my model bike for a very reasonable price. Both are water jet cut from steel stock and machined to meet BMW tool dimensions exactly. I bought a set.
 
alcutter said:
Brass, being very soft, has the possibility of peeling if it jams against something. This has the possibility of leaving fragments behind. I wouldn't use them.
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Not all brasses are soft and the type of brass used in feeler gauges is of the harder variety.
 
Tripletrouble said:
Not all brasses are soft and the type of brass used in feeler gauges is of the harder variety.
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Harder, sure, but hard enough? You can cut any brass with a blade AFAIK (unlike SS) so that leaves a chance that some particles are deposited if the tolerance is very tight.
 
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