best way to adjust valves??

What is the best way to adjust the valves on a SBC with a hydraulic cam?? I have a lunati voodo cam and the instructions from the manufacturer say to adjust the valves without the engine running by tightening the nut on the rocker and spinning the pushrod until it becomes hard to spin and then turn the nut an additional half-turn. This will preload the plunger. Once at that point you are to tightening the jam nut. IMO this is a complete ******* of a way to adjust the valves because I can spin the bloddy pushrod when the valve is wide open. I have tried 3 times now to adjust my valves using this method and I can still hear massive ticking out of my valve covers. How should this really be done, I have been told it should be done with the engine running but I tried that too and lost 5 quarts of oil all over my engine and driveway in less then 2 minutes. Please help here because I want to get this done right.

Thanks,
Keith


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I use the intake closing exhaust opening method. When I am done,I put the valve covers on and forget about it.

Do a search here on this site....it has been covered many many times.

Better Yet use the Knowledge Base on this site,
http://www.hotrodders.com/kb/valvetrain

__________________
Luv the smell of NITRO in the morning.

As do I.

It's easy with 2 people. Hand tighten all the valves have someone keep their fingers on the valves, when one starts to move down, tighten the other to zero lash (or whatever spec you use).

When the other valve moves, tighten the other.

That's it. Takes about 1/2 hour, order is irrelevant.

During an engine build or cam/lifter swap, you can adj the valves as stated in your instructions, but with the intake manifold off. This way you can see with your eyes and feel with your fingers when contact with the lifter plunger has been made. Because, as you know it can be difficult to tell depending on the state of lifter pump up with oil. often during the rotation of the engine the lifters will loose their prime and then its hard to tell. The procedure to use is to install the cam, lifters, adjust them and install the intake last. There are many other ways from A to Z and preloads anyplace from zero lash to 1 full turn have been done over the years. Your problem as you have stated it, is you cant find the point of zero lash, the adj with the intake off method will provide you the help you need. good luck with your project.

I have found that rather than spinning the pushrod, it is better to jiggle them up and down. If you're gentle on tightening of the polylock or rocker nut while you're jiggling the pushrod up and down, you can feel just when it snugs up, then go another 1/2 turn and you're good to go.

If you want to set the hyd lifters while the enige is running, warm it up first with the valve covers on. Then slow the idle speed right down as low as it will go.
then remove a valve cover and do the valves. You won;t loose all the oil if the engine is hot and the idle is slow.

"cough" overlap "cough"

to be safe and make sure its done right order does matter. adjust both valves when the piston is on the top of the compression stroke for that cylinder. there are other quicker ways, but this one is the easiest to follow and understand. As far as preload goes, tighten a quarter turn past zero lash.

Yes it really is that easy and straight forward.

Yes, I assumed the OP understands that one has to be all the way up while the other is going down. When doing it you can tell where the overlap is.

One valve should be at zero lash while the other is moving down.

I've done it this way 100 times and for an initial setup it's the easiest, most accurate way.

easier yes, more accurate no. And you're assuming a guy can figure out where overlap ends when he can't adjust hyd. valves to begin with- sounds like a risky assumption that is being made just to save from turning the crank a couple more times.

If done right is is easier, but its harder to do right that way.

Ive seen little metal clips that temporarily go on the pushrod side of a stock rocker to direct the oil downward while adjusting. Not sure where to get them though. I used to do like Fbird88 does, idle it down, and also cut a piece of cardboard out and slide it in the outer edge of the head by the valves to keep oil from making a mess. It helps a lot.

The quick old way, takes about 15min.
------------------------------------------------------ Intake-----Exhaust-
Top dead center with #1 cylinder valves closed, adjust-- #2----------#8---
Rotate crank 90* clockwise-------------------- adjust-- #1 -------- #4----
Rotate crank 90* clockwise-------------------- adjust-- #8 -------- #3---
Rotate crank 90* clockwise-------------------- adjust-- #4 -------- #6---
Rotate crank 90* clockwise-------------------- adjust-- #3 -------- #5---
Rotate crank 90* clockwise-------------------- adjust-- #6 -------- #7---
Rotate crank 90* clockwise-------------------- adjust-- #5 -------- #2---
Rotate crank 90* clockwise-------------------- adjust-- #7-------- #1---

I have adjusted valves with engines running. I used a old set of valve covers with the tops removed, you have to use the gasket to secure a tight seal. Hope this helps you... jim

I have posted this before and feel it will help you. Please read the part about the correct "feel" to get '0' lash.

Adjusting Hydraulic Lifters On Small Block Chevrolet

This method is with the engine OFF and spark plugs removed for easier rotation.

Install all the hydraulic lifters and pushrods.

NOTE: New lifters do not have to be pre-lubed. Assembly lube should be put on the cam and the mating face of the lifters.

Install all the rockers and the adjusting nuts leaving them loose. Do not tighten the adjusting nuts before adjusting the valves. Make sure the pushrod is in the lifter and the rocker arm seat when making the adjustments.

Adjust one valve at a time.

Rotate the engine in the normal direction of rotation (clockwise looking from the front of the engine) until the exhaust lifter on the cylinder that you are adjusting just begins to move up. At this point adjust the intake valve on that cylinder to ‘0’ lash with no pre-load. Then tighten the adjusting nut ¼ to ½ additional turns.

Rotate the engine over again until the intake lifter has come to the full lift and then is almost all the way back down. At this point adjust the exhaust valve to ‘0’ lash and then tighten an additional ¼ to ½ turns.

Continue the above for each cylinder until all the valves have been adjusted.

NOTE: Rather than spinning the pushrod and attempting to get the correct ‘feel’, I suggest holding the pushrod between two fingers and lifting the pushrod up and down while slowly tightening the adjusting nut. When you reach the point where there is no up and down movement you will be at ‘0’ lash.

The problem with spinning the pushrod and attempting to get the correct ‘feel’ is that you can and will still be able to spin the pushrod even if you bottom out the lifter. This can cause you to over tighten the adjustment and can lead to bent and / or broken pushrods and valves.

Priming the oil system before starting the engine will fill the hydraulic lifters.

I still prefer to set the lash with the engine running.. I seem to do somthing wrong when I do them with the engine off.. so I just stopped doing it that way ~

but IMHO it makes more sense to do it with it running.. the lifters are operating on their normal oil pressure.. which is how they need to be set.
I might be wrong.. but you know what they say about opinions

i cut a window in the top of an old chrome valve cover.. just big enough to get my socket on the rocker nuts.. and it really keeps the mess down.