Any valve lash advice from the gurus?

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Futzy1

Futzy1

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So I've got oil all down the side of my block, and I'm hoping it's just what the desert sun has done to my valve cover gasket. I'm gabbing a new one this weekend and I figure while I have the cover off I might as well attempt a valve lashing. I've read a bunch of articles, but I'm learning as I go, and honestly this is the deepest I will have ever gone into an engine. I'm hoping to do it while the engine is running. I looks like it would be much easier/quicker, but for my level it's also a little intimidating. Any pointers???
 
Before you adjust your valves run the car to get it warmed up. I use the feeler gauges that have a bend it tends to be easier for me. make sure you remember the order because there are two intake valves side by side. For the valve cover no glue just use a torque wrench if you want no leaks 35 inch pounds. I adjust them them Ex .21 in .11 little loose helps adjusting the idle lower. Its pretty easy to do kind of fun as well.
 
The EOIC method is best. Exhaust opening intake closing. Start with cylinder 1 do 1 at a time. so on cyl 1 bump motor over till the exhaust is just starting to open, then set the intake valve. Then spin motor over till the intake valve is fully open and just starting to close. then you set the exhaust. This is for solid lifter cam with adjustable roller rockers. The cam card should have a cold and hot setting for the preferred lash. My Lunati solid has a tight lash of .016
 
Slantsix64 said:
Its pretty easy to do kind of fun as well.
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Yeah I cant lie, being newer to this stuff, the whole idea of turning moving bolts on an exposed running engine kind of tickles all my soft parts. Lol. And I know my 5 year old is going to think I'm superman which is always a plus.
 
I enjoy doing it while the engine is running. Run it ten minutes then go to work. Much easier to get an accurate read and you save time and starter life not clunking the engine around twice for each cylinder. Throw a junk towel down the side to catch wayward oil, or cut a valve cover window if you have a spare one. I also highly recommend silicone valve cover gaskets. They last forever and make the annual valve lash job so much cleaner and easier.
 
If your idles down at like 600, thats 300 per minute valve cycle so 5 bumps per second on each adjuster. Use a socket and a 1/4 drive and good call on the bent feeler guages. I'd get it hot and shut it down, adjust all the rockers and then start back up and check while running. I bet 90% will still be spot on. I would adjust closed valve while opposite is wide open.
 
If this is the only thing you learn how to do on that Slant six you got about three-quarters of the tune up down packed! Every time I've had one of these I've done a valve adjustment and had great results because nobody seems to do them. They need them.
I personally recommend the very first time you do this not to have the motor running! This is your first time and you already sound a bit intimidated and having moving parts and noises going on while you're trying to do something doesn't sound like a good idea. I've done this several times and never once have done it running not to say that's not a better way or anything but it just seems safe. Also if you're comfortable with pulling all your plugs out and knowing your firing order then it would be easy to turn the motor over with them out. My-2
 
Thanks for all the help guys. I love this place. I think I'm going to at least try running first. I l tend to be a leap then look kinda guy and it usually works out. And if it stop much, I can always kill the engine and turn it by hand.

Anyone have a good way of describing exactly how much tension I should have on the feelers when the spacing is right?
 
Futzy1 said:
Thanks for all the help guys. I love this place. I think I'm going to at least try running first. I l tend to be a leap then look kinda guy and it usually works out. And if it stop much, I can always kill the engine and turn it by hand.

Anyone have a good way of describing exactly how much tension I should have on the feelers when the spacing is right?
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I really like the go no-go feeler gauges for a novice like myself. I know for a fact that these guys know what they're talking about when they say that you should use the bent one.
 
Let's say you want .020/.020 at the valve tip. Grab a .020 feeler gauge and stick it in there on a HOT relaxed valve. If the thing slips in and you can rock it, tighten the adjuster until you can feel it drag or you can spin the pushrod and tighten until you feel the slightest difference in the tension. That's all. No more. Usually when the motor is running you are moving it back and forth under the rocker arm and tightening the adjuster until you feel the same drag on the closed cycle of the valve. Remember the valve will be grabbing the feeler gauge every opening cycle so just go with it. It's pretty nerve wracking the first time when you think the socket will fall off and go down the abyss.
 
In my experience on the slants I have had; the valve stems tends to wear grooves in the arms. I use narrow feelers that fit in the grooves. They are just regular feelers snipped to size.
I do each cylinder at TDC-compression, working thru the firing order. I marked my balancer at 120* intervals so the whole process only takes two revolutions. And I leave the plugs in, cuz the Dcr on on mine have always been so low,they are easy to turn over by hand.
 
21 and 11 , the truck spec . Lets 'em sit on the seat just a little longer to cool
 
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Futzy1 said:
What is the point of going over spec anyway? I see that all over the place.
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I like setting them looser i dunno why but they seem to idle smoother and run better on a stock slant six camshaft though. It took me a while to figure out how to set my lash for my clifford performance camshaft due to it being installed in the engine when it was rebuilt before i purchased it. i had no card to go off of. i ended up with Intake.16 Exhaust.18 and it runs great with a nice beefy idle.

It is said that setting you valve lash looser helps with compression, so on a worn used motor it will wake it up a bit.
 
I set them loose Because I know they will run there. Then over time I try a little less and a little less and eventually I wonder why it's running so crappy. Then I put .002 back in the lashes and Badaboom!, life is good again. I always come back to .012/.013 and .023ex. That's what mine likes.
 
Slantsix64 said:
I like setting them looser i dunno why but they seem to idle smoother and run better on a stock slant six camshaft though. It took me a while to figure out how to set my lash for my clifford performance camshaft due to it being installed in the engine when it was rebuilt before i purchased it. i had no card to go off of. i ended up with Intake.16 Exhaust.18 and it runs great with a nice beefy idle.

It is said that setting you valve lash looser helps with compression, so on a worn used motor it will wake it up a bit.
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That's why I use a box end wrench
 
So this is another amature question, but what are the signs of too loose and too tight?
 
A tight valve can cause the engine to miss or run a bit rough; a loose valve is a little noisy. Don't be surprised if you hear a little noise from the valvetrain; if you adjust all the noise out, they're probably too tight.
 
And if it continues to run too tight, say on a long trip, the valve will overheat and start to; lose it's shape, crack, or burn up. And then the pressure falls to near zero, and try to idle a slanty on 5 cylinders and you'll see what happens. With zero compression in one hole, it might idle a bit better than with one plugwire off.
But I gotta tell you, it's rare that just one valve burns up,lol.......
 
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Aaron65 said:
A tight valve can cause the engine to miss or run a bit rough; a loose valve is a little noisy. Don't be surprised if you hear a little noise from the valvetrain; if you adjust all the noise out, they're probably too tight.
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If a valve lash is tight enough to "cause a miss" then THAT VALVE is going to be BURNED in a short time. The CAUSE of the miss is leakage past the valve seat because the valve is held open.

If you get valves "way too" loose you can hammer stuff in the valve train, IE deform the pushrod ends or rockers

the EOIC method mentioned above WORKS ON ANY poppet valve type engine.

It means rotate the engine until the EXHAUST valve just starts to move OPEN, and adjust that intake, then rotate until the INTAKE has fully opened and is "on the way" CLOSED, and then adjust that exhaust.

Camshaft - Car Craft Magazine

Learn it and use it. You are welcome
 
Screw that runnin chit. It's stupid and dangerous. Set them .002" loose when cold and they will be perfect. To hell with what the so called experts say. Be safe.
 
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