Tips for Adjusting Valves
John Moeller - June 19, 2000
Stefano Paris - June 6, 2000
RGAZ - June 6, 2000
snakeyez - June 6, 2000
William NG - June 6, 2000
Tyson Lee - June 6, 2000
Caleb V - June 6, 2000
Dan Loncher - June 13, 2000

I asked the forum for their tips on adjusting their valves since I didn't do mine properly. I got many answers, all of which offered good suggestions. There was some overlap, so I'll try to condense it down right here, although it's time well spent to read it yourself and perhaps print it out if you're a do-it-yourselfer. If you have any individual questions, their emails are provided, but read the whole thing first.

1. Use a feeler gauge that is lubricated with oil or assembly lube. This will allow the gauge to slide more freely and cut down on friction preventing you from adjusting loose erroneously. If you use assembly lube, it would be a good idea to adjust them before an oil change so that the gunk can exit the engine.

2. Keep an eye on how you're holding the feeler gauge. If you hold it at an angle, then you're not measuring the gap correctly. You're including additional clearance, and they will still be loose.

3. When tightening the locknut, use the screwdriver to hold the adjuster in place. If you don't, you could be loosening/tightening them inadvertently. Snap-On makes a tool do this for the DOHC VTEC motors, I don't know why it wouldn't work with the SOHCs too.

4. Also when tigthening, leave the feeler gauge in between such that you can check it and make sure your measurement is still accurate.

5. Your motor must be cold for proper adjustment. Let it sit overnight. Kind of makes you wonder about those who take it somewhere, and if they time they're letting the car sit is sufficient.

6. If nessecary, bend your feeler gauge. I made an L out of mine so that I could get it down there easier. Remember to bend straight, or else you risk violating tip #2.

The greatest confusion is going to be determining what amount of drag is correct. I think as long as it as snug, you should be ok. I'm not sure that hearing the metal "chirp" is a good idea, but perhaps that's more exaggerated with a dry feeler gauge. Everyone more or less suggested to err on the tight side of the factory recommendations, and don't overtorque the locknut, ethier.

Anything to add?


I've been adjusting my own valves for 15 years... I generally find the feeler gauge that is in the middle of their spec range...and adjust around that. I make sure the feeler isn't generally get it coated in oil anyway when doing valve adjustment.

It should slide in and out smoothly...snug...but not grinding snug. Tough to describe in words.

What I found I like end up doing I don't have to adjust/check often (the valves seem to stay in adjustment on my cars for 50,000miles,etc..) is I'll adjust them to the outer spec which allows for valve seat wear (larger more "play"). As the wear happens on the seat...the valve play stays within spec longer. This is barring any wear on the valve stem head itself.

Easiest rule of thumb I go with would be shoot for the middle...with the feeler being snug but sliding smoothly.

I used to check my valves every 15,000mi...but damn if they don't stay adjusted...even after 30,000mi...

Good luck!

Stefano Paris

1. Go for "consistent drag", meaning the same drag felt for all valve clearances.

2. Keep the feeler as flat as possible.

3. Err on the tight side of the range vs. the wide side.

4. I use a very thin layer of assembly lube on my feeler gauge to help with restart.

5. Like carpentry: "measure twice, adjust once".

6. Engine should be cold, I let mine sit for at least 12 hours with the hood open.

7. I always take my time.


"How much valves should be adjusted"
That's one thing that isn't noted on the instructions.

It definitely cannot slide easily back and forth. You will notice that the strip will slide differently depending on which side you are working on (Inlet or Exhaust). Try to make them the same all the way ACROSS on the inlet side, and same for the exhaust side. The amount of drag felt on the exhaust side can be different from the amount of drag on the inlet side since you are using different guage strips. Also it MUST have drag, but not so much that you can't pull the strip out.

So here is how much I've been tightening:

Tighten it enough so that when you slide the strip back and forth it will make a squeaking sound. In order for this to occur there must definitely be a good amount of drag: which is enough to make the squeaking noise, but also enough to allow you to create that noise.

I've adjusted the valves on a few ZCs like this and everything runs well.

Remember though, the noise coming from the engine when it is running is excessive when the valves are too loose. That is why I tighten them with the extra amount of drag (yet it still stays in spec). HTH


The most important things I wanted to say was said more or less by the other posts. Did wanted to add that upon tightening the retainer nut, the compression will screw up the original gap that you set. It takes a couple of tries to find the right fraction of turn to compensate.

Also, I like to refer to the 'sweetspot' of gapping is when the feeler starts to resonate a bit as you slide it back and forth perpendicular to the gap. Once it starts 'singing' like a well-rosined bow across a violin string, you're done.

Editor: If I tigthen the locknut without using a screwdriver to hold it in place, what happens?

The gap increases. You tighten/lossen a few times until you get accustomed to the drag caused by compensation. But you get the hang of it pretty quickly.


while i cant say im an expert, what ive found the two times ive adjusted my SOHC is that the intake valves are really hard to measure right. often i get fooled because im inserting the feelers at an angle and think its tight enough, yet if i try it again at the right angle, it was in fact pretty loose. so make sure you fiddle with it to make sure youre feeling the "loosest" possible reading.


For SOHC motors buy a set of bent feeler gauges and it is easier to manuever them on the backside of the head especially around the valve cover studs. Not needed as much for DOHC motors but still helps. If you have a straight set just bend each one individually approx. 1" from the end.


do it right before an oil change. That way, any dirt you get in their can be run out of the engine as quickley as possible.

Dan Loncher