Yesterday I adjusted the valves on a '94 22RE engine. There was an occaisional tapping from the driver's side rear of the engine, that I thought I could fix up with a valve adjust.
I got everything up to operating temp and then removed the valve cover, set it to TDC compression, etc, adjusted the intake valves to .008 inches and the exhaust valves to .012 inches just like it says in my book. Turned 180 degrees, adjusted the other set, etc. I've done this before on a few other 22Rs with good results.
Now, with this engine, it sounds great cold, but the occaisional tapping from the driver's rear is constant once the engine gets up to operating temp. None of the adjustments were far off. A few were a bit tight, and a few were a bit loose.
Why is it tapping now?
Thanks.

 

Either too loose - or sticky valve...

If the valve isn't sticky - then, you know, too much clearance is better than not enough. If too much will be loud and affect power a little bit. But, at least you won't burn a valve.

 

I would think that if it was a clearance problem - it wouldn't "Occasionally" tap - it would tap all of the time.

 

Well, I'm confident that I did the adjusting correctly.
The clearances are good. It does tap all the time now at operating temp, just not when cold. Before it would tap only at certain RPMs.
Is there a tried-and-true method for trying to unstick valves on FI motors? On carbureted engines I pour ATF and water down the carb, and it does a great job of cleaning up combustion chambers. Don't know much about how to clean up FI systems...

 

Well, if it taps all of the time - that is good. It's just a little loose.

On most engines - (I don't know about the 22re) you adjust the valves when it is dead cold. Not when it is at operating temperature.

 

Nope, I looked in my book - you are suppose to adjust at operating temperature. My bad...

If it runs good. I'd let it ride and turn up the radio....

 

I have had a few 20R/22R's In my time and have always adjusted them hot and always a thou or two tight when they were older to quiet them down. I never once had a problem going a little tight and all tolled I probably put 150,000 miles on those engines.

 

The 20/22 top end is a noisy design, if it's running quiet then it's too tight. .007 and .011 cold seems to work best for most cases. Other possible causes of a "tapping" sound are piston slap or a loose wrist pin.

 

Hmm, drivers side rear... could also be an exhaust leak.

 

So, you're looking at a thousandth of an inch tigher than spec? Yeah, that should work. I'm just bummed that I adjusted the valves on a friend's truck to try to make a top end noise go away - but it just got louder. I thought about exhaust leak, but figured that an exhaust leak wouldn't show up immeadiately after a valve adjustment, ya know?

 

Ya but read carefully, that's .007 and .011 COLD. Lots easier than having to warm up the engine then race to get them all adjusted before it starts to cool down.

 

Yet another possibility, any chance you overtightened the valve cover? If you crank it down too much the rockers will contact it...