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Discussion Starter #1
I decided to bite the bullet and check my valves myself after I read all the posts.

They actually seem to be in pretty good shape gap-wise with the exception of the intake valves on #1 cylinder. The 0.127 feeler goes in nicely, the 0.152 takes some more serious pushing to get it in. Once in, it is very snug but I can move it around. The 0.178 gauge will not go in at all.

I've included a chart showing my results:
yellow is easy
light green is snug
dark green is very snug
red is can't insert

My tendency is to leave it alone and close it up, but I'm not sure how critical these measurements are.

Any advice??
 

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I think you are OK. the #1 intake will probably require replacement in 12-24k miles.
Everything else should go a long time.

dan
 

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The normal ware on valve clearance is from loose to tight. All of your clearances are on the tight side of the specked range. Mine were like this at 48k and I waited until 60k to do the adjustment. I was able to rotate 10 of existing shims to new locations and replaced 6 with new ones. If your only thinking of doing one, I would wait an do them all at the same time. You want to be on the loose side of the specked range as much as possible. That is my .02.

Oh, on the feeler gage you want light resistance nothing that is snug...
 

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No way to know what you mean by "snug", or "tight". The best way to know clearance is by using individual feeler gage strips, held between two slightly oily fingers. If you can push it in easily this way, you probably have a pretty good fit. If you are pushing very hard at all on the gage, you are actually opening the valve slightly.

If you REALLY want a good measurement, use a dial indicator on top of the valve spring cap, push in a larger feeler gage, and subract the indicator reading from the gage thickness.

For instance, use a 0.010" feeler, and if you get 0.004" indicator movement, the clearance is 0.006". Very few of us have or use metric gages, but use the inch readings instead.

From many years of experience, I can say that MOST people push too hard on the feeler gages and get bad readings, with valves tighter than they think they are. Better to have them slightly too loose than slightly too tight.
 

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Another way to see if you're getting the right "feel" is to use a micrometer that has been calibrated.
Set the micrometer to the thickness of the feeler guage & then side the feeler guage through the gap in the micrometer.
That's what the proper "drag" should feel like.
Chris Barritt
30+ years as a M-Benz Tech
'00 LT Canyon Red (Big Red)
'02 R1150GS Grey (The Tank)
'99 LT Balsat with 145k (The Starship Enterprise) RIP :-o(((
 

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If the valves are out of spec get them adjusted. They gave them a tolerance spec for a reason, and if you choose to ignore it you may as well skip checking the valves altogether.
 
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