more valve adjustment questions

[Alan Cottrill]

.004" is the valve adjust spec. right?

does that account for the film of oil between the top of the valve and the adjuster screw?

[Formerly Steve Wilkinson]

Yes, .004 is correct, and if you mean by "film of oil" allowing enough slack in there so the adjuster tab floats around loosely in a cushion of oil, no, that's not intended. Does it account for a microscopic film of oil? Well, I guess so...what you want to do, and it's in part a matter of touch and experience, is achieve a gap between the valve and the actuator/adjuster tight enough that the feeler gauge moves between them freely enough that you don't have to "pull" it but not so freely that it moves...well, freely.

It's something you have to get used to. You can slack off the nut a bit and, after you get the feeler gauge in the gap, screw down the adjuster enough that you can't move the feeler gauge. Then you back off enough that you _can_ move the gauge, but not so much that it just slips around with no effort. Then hold the screwdriver in the slot and tighten the adjuster nut, and like as not you'll have tightened up the gap just a skosh too much, so you go back and do it again.

I understand that in a Turbo, it's _real_ fun.

Stephan

[pbs911]

One thing I have heard done is to get .005 feeler guage. Adjust with the .004. Then check with the .005. If it fits then the adjustment is too loose.

[movin]

Always check your gauge's true thickness. Don't trust the printed designation, verify! I have found quite a few slightly overlythick by .0005" to .0007". I simply honed them down to precisely .004"

[Joe911]

Always wondered - why not check the lash between the cam lobe and the rocker? So much easier to get at. I know that unless the rocker ratio is 1:1 the clearance would not be .004.

[snowman]

You should be using a dial indicator, not a feeler guage on the 911.