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Tips
Tips

Adjusting valves makes me more crazy.

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Tinster

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There has to be some trick mechanics use to get valve
adjustment correct. I spend hours and hours and hours and
never get them spot on. I'm trying make the final adjustments
after break-in driving 200 miles on my reconditioned rocker
arm/shaft assembly.

I use the Bentley method- for example: Rotate fan until
valves 10 and 12 are fully open. Set gap of valves 1 and 3.
Etc, etc until all valves are gapped to .010"

So I repeat the procedure to insure I did it correctly.
Nope! Some valves were out of .010" spec. So I reset them all.

Repeat the procedure to make sure I got it right THIS time.
Nope! different valves now out of .010" spec.

I seem to have an eyeball problem determining exactly when
a valve spring is fully compressed. The two full open valves
never have the same amount of downward movement of the springs.
Why is this?

My car runs pretty good but I would like to master valve adjustment and have my valves on spec.

All suggestions welcome.

best regards,

dale
 
Hi Dale - it can be hard to tell exactly where the absolute open is sometimes. My bet is that you are probably well within tolerances for the car to run well. Maybe others will pass along more helpful info.
 
Dale- You ain't racin the thing. Just drive it and quit worrying about it.

And that's all I'm gonna say
 
Don't 'over-tech' it. If they don't rattle and there's clearance, you're done. Only hard and fast rule is: "better to be a bit too loose than too tight."


Drive on.
 
Moss sells a valve adjusting tool for about $100 a little expensive but may be worth the cost!
 
I just set the exhaust to about 0.012" and let them make a bit of noise. most manufacturers spec the exhaust looser than the intake anyway. The intake valves stay much cooler so they don't expand nearly as much. Either way if they are a tiny bit loose it won't hurt anything, just that last 1% of power no big deal.
 
Thanks all! The car does run better than
ever, although I have nothing to compare it to.

Doc- I have a valve tap on No12.
Is that too loose or too tight.

Thanks Tinman58 but funding is tighter
than the opener of a Scotsman's coin purse!

dale
 
Well, at least you can adjust yours.
You want hair-pulling, try either a Flathead V-8 or a Jag.

Now, over the years, I have seen all these "with exhaust valve #3 open, adjust the following valves...."

Never was happy with the results.
So, in the shops, here is what I did, and do:

Yellow tyre crayon.
Rotate engine by hand (with all plugs out) until the valve you want to adjust if fully OPEN.
Rack the engine back and forth until you are fairly certain.

Mark the head next to that rocker, and then mark the damper to either a timing pointer or something you can easily spot.

Rotate the crankshaft one full turn, until the pointer on the damper lines up once again.

This rotates the cam 180 degrees, and you are absolutely certain that the lifter is on the base of the cam.
And, since the base is fairly wide, you should not have any issues.

Now, mark the rocker and remove the mark from the head.
Rocker marked, adjustment done.
Remove the damper mark and do it for the next valve.

Wipe everything down when done.

On the rockers, you can use tape, string, clips, anything you want.
 
Tap is too loose.
If you want to really get fine.......start it up with cover off, use a .002-.004 feeler, slip it between the rocker and valve stem while running.

The one making noise will quiet up a bit.
Then, fine-tune the feelers, by .001", until you know the exact point at which that rocker becomes quiet.

That is the amount of rotational slack coming from rocker/shaft/pushrod that you are not, for some reason, feeling with a engine-off adjustment.

I would try the marking of the damper and 360 turn of the crank from full open and check again on those valves....
 
If you stuff a feeler gauge into the tappet as it is running, be prepared to call that gauge junk afterwards, BTW.

If #12 is rattlin' just close it down by a thou or so.

Again, too loose is better'n too tight. Don't obsess over it. It *HAS* to be better with the new shaft, etc.

Go fer a drive. :wink:
 
Dale,

I have been over the valves on my Spit twice now. Still a bit noisy. I just leave them be and drive the car. I would rather the noise than be too tight and burn a valve.
 
TOC said:
Well, at least you can adjust yours.
You want hair-pulling, try either a Flathead V-8 or a Jag.
Click to expand...

Yes, on the flat head, pull the intake manifold and the heads, check the clearance. If not enough, take out the valve and grind the valve stem, if to much, take out the valve spring and lap the valve. I dropped a lot of those little clam keepers into the pan. Finally got smart and got the lifters with the adjusting screw. So now I only had to pull the intake manifold.

Did the Jag thing as well, I loved the measure, lift the cam, and shim bit.
 
Dale you can do the 13 method, Pull the spark plugs out makes turning the engine much easier valve one is at the front of the car valve no 12 is toward the rear
valve no 1 down adjust 12
valve no 2 down adjust 11
valve no 3 down adjust 10
valve no 4 down adjust 9
valve no 5 down adjust 8
valve no 6 down adjust 7
valve no 7 down adjust 6
valve no 8 down adjust 5
valve no 9 down adjust 4
valve no 10 down adjust 3
valve no 11 down adjust 2
valve no 12 down adjust 1

once you get the valve in the down position you can put a magnetic gauge on it to make sure its totally down but thats kind of over kill, you will get really good at it once you are done. and you can go back and verify them pretty fast but sometimes to get the next valve down you might have to rotate the engine 2 turns

Hondo
 
Thanks all,

I'll give it another go, button it up and get back on the road.
 
DrEntropy said:
If you stuff a feeler gauge into the tappet as it is running, be prepared to call that gauge junk afterwards, BTW.
Click to expand...

Not necessarily.
However, I have 5 or 6 sets, some are used in adjusting (running) 235 Chebbies, 226 slant 6's.....and you do those running.
I even have the tool for holding the nut and tang at the same time.

Part of the issue of doing static valve adjust first, second, even third time, is you may not know the "feel" of what a properly adjusted rocker is like pulling a feeler out.

And, I have done LBC's running when all else seemed to fail.
 
At least you don't get a bath of oil when doing a TR6 like you do a Chebbie when setting with engine running.
 
Tinster, I know you're working on a TR6, but I believe there's a helpful article at Macys Garage. www.macysgarage.com/myweb6/valve_adjustment.htm

Adjusting the valves is much easier when you realize that valve adjustment corresponds to intake and exhaust strokes.

I had the same problem you describe, but the "Article" helped a great deal. It explains what it means when a valve "just starts to open" or "just starts to close." It's not the same as "eyeballing" full up or full down. It's the point of "just starting," and it's more accurate.

That way, when you use the feeler gauge to find .010, you'll be in the right place.

In short, you can't just eyeball when a valve is fully closed and ready to open, or vice versa.

For example, when an intake valve is just ready to start to close (come back up), the exhaust valve is adjusted. Watch the intake valve. Just as it starts to come back up, the exhaust valve is fully closed and can be adjusted.

When the exhaust valve if fully up, but just starting back down, you adjust the intake valve. For a six cylinder engine, you can't use the Rule of 9s, but you still follow the above procedure.

I hope that helps.
 
I believe that article is how I said to adjust the valve but for a 6 cylinder itss the rule of 13, but great article and more indepth than my description but I have been doing it for a while

Hondo
 
Good- except, what do you do if all you have is the lash?

I've done hundreds if not thousands of valve adjustments by finding the base of the cam, and they are quiet.

I have also had innumerable vehicles come in with VERY noisy valves, and the customer "did it by the book".

I have not seen good results doing it that way.

But, hey, when you're out at the side of the road, and something comes loose, and you're trying to remember which valve open, which valve adjust, remember how to do it without that process.

The base of the cam is wide (degree-wise) and once you roughly know where full open is, 360 on the crank puts that lobe 180 opposite the lifter.
 
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