valve clearance

[rudi]

Yesterday evening I have adjusted the valve clearances with a feeler gauge. I have done this before. By doing so I asked myself the question how thight in fact the clearance should be. Should the feeler gauge pass easy or should the rocker be thight on the feeler?

Cheers, Rudi

[gwr]

Rudi,

 

The feeler should be able to slide through the gap. You should be able to feel both surfaces bearing very lightly on the guage as you do so. When you have set the gap you should be able to withdraw the feeler quite easily, it shouldn't be pinched at all.

 

Hope that helps.

[Dale Moore]

Hi Rudi

Gordon is correct, there should be only a light "draggging" of the feeler guage through the gap. However if there is wear in the face of the rocker arm, at the point where the rocker contacts the valve stem, (normal place!) passing the feeler guage through the gap will not take that into account, and will result in a larger gap and noisy tappets!

Regards

Dale

[BrianC]

...if there is wear in the face of the rocker arm, at the point where the rocker contacts the valve stem, (normal place!) passing the feeler guage through the gap will not take that into account, and will result in a larger gap and noisy tappets!

That's one advantage of the click-adjuster. My preferred option is to set the gap initially with one of these and then check using a feeler gauge. If there is significant localised wear, it's probably worth using a slim-line feeler gauge (cut-down feeler or suitable strip of shim steel). I have always assumed it's better to err on the side of caution by having the gap slightly larger, rather than too tight. Better to have a little noise than burn out the valves/seats. Is this correct?