[norustscott]

I would be highly suspect of anyone who describes a valve adjustment as " 3-4 threads tight". On a stock adjuster that would equal something like .100". Way too tight, as in valve is propped open and never shuts. I would run from a mechanic that describes the adjustment as such. He/she should be speaking in thousands of an inch as in .006".

Lets assume he meant .003-.004" tight. With a valve adjusted cold to .003" you could get a tight valve when hot. Tight to the point of poor compression, yes. At idle the engine will run rough. almost like a miss. Rev it up and it might smooth out, but not much. Easy to check. run a compression test. A cylinder with a tight valve will have less than the others.
An engine in good condition, you would expect to see 135 or better psi. On a cylinder with a tight valve, I would expect to see 90 psi or worse even 35 psi or zero depending on the open clearence.

Now, If you don't have a compression tester, let the engine idle, if it is running rough, start pulling plug wires one at a time. you should hear a change when the plug wire is removed, a drop in rpm and an even rougher idle. If not that cylinder is probably the tight one. If it is a tight intake valve, then you will find a black soot coated plug, while the others will be clean.

If you have hydrualic vavles...this is a diferent story. The "Thread" description holds a little more water, Hydro are adjusted hot...1.5 to 2 turns past contact with the valve stem....the noise could be a bad hydro lifter not pumping up. Once the correct hydro adjustment is made, the lifter may have too much clearence...We can go further into hydro details if this is the case.

Better yet, print out the pelican parts how to adjust your valves article and tackle the job yourself...nothing bonds you to an aircooled engine like adjusting valves...An gives you total peace of mind...








Vavle noise is typically form a Loose senario. .008" and up will have a diffinitive clicking rather than the plesant "sewing machine" sound. A tight valve is really quiet...