[jsabowabo]

I'm adjusting the valves on my 69 Camaro, hydralic flat tappet. I set the engine to TDC on #1, I can feel the compression blow on my thumb. I adjust the half the intake and exhaust valves. I crank the engine over two full revolutions, and I can no longer feel any compression on #1. I crank it over again two full times and still nothing.

I then back off #1 intake and exhaust rocker arms until I can turn the pushrods with my fingers and I get compression blowing past my finger again. What's going on here?

After I adjust my valves I should still have compression on all cylinders blowing past my finger on TDC for that cylinder. What am I missing here. My technique is to adjust the rocker until I can no longer twist the pushrod, then tighen another 1/2 turn on the rocker nut.

Thanks
Jason

[jsabowabo]

I figured it out. I was adjusting the rocker arms too tight. I ended up adjusting the rockers until I couldn't fit in a .010" feeler gauge, then doing another 1/4 turn on the nut.

[cd playa]

The best way is to set them while the engine is cold and not running, oil makes big mess especially on a new or clean engine.
Set the balancer on 0 degree with number 1 piston on compression stroke adjust Exhaust Valve on 1, 3, 4, & 8 adjust intake valves on 1, 2, 5, & 7. Rotate engine one complete revolution and adjust exhaust 2, 5, 6, & 7 adjust intake 3, 4, 6, & 8. Adjustment is easy and engine only has to be rotated or move once.
When making adjustments while rotating push rod with finger tips until push rod stops turning, don't apply very much pressure while rotating the push rod. When you get to the point when push rod stops turning rotate the nut an additional 1/2 turn.

[JimM]

I do em running. get er good n hot, pop one valve cover, clean the rail and duct tape a towel on.
start it and run that side in 20 second.
put the valve cover on and repeat on the other side.
no mess really, cept on the towel. Only way to really get hydraulics right.

[camcojb]

Originally Posted by cd playa

The best way is to set them while the engine is cold and not running, oil makes big mess especially on a new or clean engine.
Set the balancer on 0 degree with number 1 piston on compression stroke adjust Exhaust Valve on 1, 3, 4, & 8 adjust intake valves on 1, 2, 5, & 7. Rotate engine one complete revolution and adjust exhaust 2, 5, 6, & 7 adjust intake 3, 4, 6, & 8. Adjustment is easy and engine only has to be rotated or move once.
When making adjustments while rotating push rod with finger tips until push rod stops turning, don't apply very much pressure while rotating the push rod. When you get to the point when push rod stops turning rotate the nut an additional 1/2 turn.

just realize that this won't work with most solids including the 30-30 factory cam. Also it is not completely accurate on hydraulics, but there is some "fudge factor" with a hydraulic.

I much prefer the exhaust opening/intake closing method.

http://www.cranecams.com/?show=techa...e24a0ef0b5928a

Jody

[cd playa]

got my info from here, see link.
http://www.2quicknovas.com/happyvalves.html

[camcojb]

Originally Posted by cd playa

got my info from here, see link.
http://www.2quicknovas.com/happyvalves.html

I like his method #2 which he uses; it's the one I linked above. The problem with his other way is that most aftermarket cams have completely different opening and closing ramps than they did 30 years ago, and that first method will put you on some of the ramps, so you do not get a true correct adjustment. The valve will be closed, but the lifter is not on the base of the lobe, it's on the ramp. Really critical with solids, but I prefer the EO/IC method for all types of lifters as it's accurate.

Jody

[Steptoe]

Set them cold to get close to the ball park, then while running back each off, till adudable clack , wind down to no clack, then another 1/2 to 3/4 turn

I have an old set of tappet covers with a strip cut out of the center, allowning access to the nut but stops oil spurting out on the inner gaurds.

[onovakind67]

Why is it deemed necessary to re-adjust them while running? If I can adjust a set of solid lifters to within 0.001" using the ICEO method, why can't I do the same with a set of hydraulics? I've always set mine with the engine off. If you are adjusting them 1/2 to 3/4 turn after you determine the zero lash point, what would be the difference in preload between 1/2 turn and 3/4 turn?

[dawg]

Valve Adjustment Procedure

1. Valves can be set on a hot or cold engine. A cold engine is a lot more comfortable to work on. Major camshaft manufacturers recommend setting valves cold, to avoid erroneous adjustments on lifters that may be "pumped up" If you are setting valves on a fresh engine that has not been run, everything should be well lubricated before you begin.
2. Remove both valve covers and remove the spark plugs to make the engine easier to turn over. Also, If you are setting valves on all cylinders, it is generally easier and less confusing to just loosen all of the rocker arm adjustment nuts before you begin. This also allows for all of the internal lifter plungers to return to their "home" position.
3. Using a long handled ratchet or breaker bar attached to the crank bolt, turn the engine over in the clockwise direction.

A. Starting with #1 cylinder, turn the engine over until the exhaust pushrod just begins to move up.
B. At this point, stop and adjust the intake valve on the same cylinder.

1) Tighten the rocker until you can roll the pushrod between your thumb and forefinger with the slightest bit of resistance.
2) At this point tighten between an additional quarter to half of a turn.

C. You have now adjusted the #1 intake valve. You will now want to turn the engine over while watching the same intake pushrod that you just set, it will go full open and then begin to close. When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. By following this procedure, you are assured that both of the lifters are at the base circle of the cam and that there is no additional pre-load applied to them from cam lift at this point.
D. You are now able to repeat this procedure on the remaining cylinders.

4.Re-install your valve covers and your valve adjustment procedure is finished

or for a more indepth explanation/ procedure:
VALVE ADJUSTMENT PROCEDURE ... THE CORRECT Way
All the time people ask how to do this procedure, and it seems that everyone they ask gives them a different answer. Let's see if I can make this easy to understand for just about everyone. Read this entire article to understand correct valve adjustment procedures for most engines.

Introduction to Adjusting Hydraulic Lifters:

The simplest way to adjust a hydraulic or solid lifter cam whether it is a tappet or roller cam is described below. But FIRST, what you need to forget about is all that information that many individuals (and books) taught you in the past. In many cases, if interpreted wrong you could be in for more trouble than before you tried to adjust the valves yourself. Think about things that can affect your valve lash, you will need this bit of common sense before you get into this, because there are other considerations besides just putting a wrench on something and attempting to follow the cam card, or shop manual.

What type of cam are you running? (Hydraulic, Solid, Hydraulic Roller, Solid Roller, Mushroom Tappet)
Are you running aluminum heads?
Are ALL of your valvetrain parts in proper working condition?
Are your valve springs the correct ones for the camshaft and operating RPM?
What type of driving (or racing) are you going to be using the engine for?
Do you have the tools and basic knowledge required to adjust your own valves?
The last one is quite important. If after you read through this and are still a bit confused, give up and have someone else do it, or have them at least walk you through it to make sure you understand the procedure. Now, if you are wondering what can go wrong there is a quite a few bad things that can occur:

Poor running engine and low performance
Failed smog testing (if this is a smog-legal street driven vehicle)
Burnt exhaust valve(s)
Broken valvetrain components (springs, pushrods, lifters, camshaft)
Limited lifespan of valvetrain components
Excessive valve guide and seat wear
Blown up engine
Lose an important Race!
Empty Bank Account
The above list, though quite simple to understand, should scare you. It takes only a few thousandths of an inch of adjustment error to cause those problems. Now lets' get to the actual process. I am going to simplify this a bit, so if your valvetrain is somewhat different you will need to verify the correct procedure for your application.

--------------------------------------------------------------------------------

Valve Adjustment The Quick Way:

Ok, now to the good stuff! First, view this little chart for Small and Big Block Chevy Engines that I made and see if you can understand it ... for other engines, use your firing order that matches your engine to do the same. You set up this procedure based upon "opposite" cylinders of your firing order. (see below)

Intake Valve Adjustment: ENGINE OFF!

with #1 cylinder Intake Valve at full valve lift .... Adjust #6 Intake Valve
with #8 cylinder Intake Valve at full valve lift .... Adjust #5 Intake Valve
with #4 cylinder Intake Valve at full valve lift .... Adjust #7 Intake Valve
with #3 cylinder Intake Valve at full valve lift .... Adjust #2 Intake Valve
with #6 cylinder Intake Valve at full valve lift .... Adjust #1 Intake Valve
with #5 cylinder Intake Valve at full valve lift .... Adjust #8 Intake Valve
with #7 cylinder Intake Valve at full valve lift .... Adjust #4 Intake Valve
with #2 cylinder Intake Valve at full valve lift .... Adjust #3 Intake Valve

Exhaust Valve Adjustment: ENGINE OFF!

If you have noticed, this is the same procedure as the intake valves listed above, just that you are now adjusting the exhaust valves the same way.

with #1 cylinder Exhaust Valve at full valve lift .... Adjust #6 Exhaust Valve
with #8 cylinder Exhaust Valve at full valve lift .... Adjust #5 Exhaust Valve
with #4 cylinder Exhaust Valve at full valve lift .... Adjust #7 Exhaust Valve
with #3 cylinder Exhaust Valve at full valve lift .... Adjust #2 Exhaust Valve
with #6 cylinder Exhaust Valve at full valve lift .... Adjust #1 Exhaust Valve
with #5 cylinder Exhaust Valve at full valve lift .... Adjust #8 Exhaust Valve
with #7 cylinder Exhaust Valve at full valve lift .... Adjust #4 Exhaust Valve
with #2 cylinder Exhaust Valve at full valve lift .... Adjust #3 Exhaust Valve





What about the actual adjustment procedure you ask?
Hydraulic Cams:

Ok, let's get to the actual wrench turning ... how many of you read or were taught that with a hydraulic lifter cam you adjust it down to where there is pushrod resistance (zero lash) and then turn it down 1/2 to 3/4 turn? Well, if you did this, you more than likely have the valves not closing all the way!

The hydraulic lifter requires roughly a .030" pintle depth setting. This means that you adjust valves by the depth that the pintle in the lifter drops. Too tight and the valves do not close, too loose and they rattle and do not open properly and damage the lifter. How do you get .030"? Well, on new engines I will actually use a dial indicator and measure the depth of travel. On an engine in the car this is a bit different, and harder to do..

Now, I have two ways that I use to adjust hydraulic lifters. One uses the "clean" method with the engine off and the other is the messy way with the engine running.



--------------------------------------------------------------------------------

Engine "OFF" Hydraulic Lifter Adjustment:
Warm the engine by running it until it gets to operating temperature (15-minutes or so). Have all your tools ready and then quickly remove the valve cover(s) and start the adjustment procedure by using the chart above. With the #1 Intake valve at FULL LIFT (this means that you spin the engine until the Intake valve on the #1 cylinder is fully open ... you can tell this by the rocker arm pushing the down until it goes no further) you can now adjust the "opposite in firing order" cylinder (see the above chart). In the small and big block Chevy engines this is the #6 cylinder. Loosen the rocker (if using roller rockers there is a Jam Nut that you must loosen with an Allen Wrench). Now, with two fingers spinning the pushrod between them to feel for resistance you easily snug the adjustment nut. When you feel resistance STOP, now you will adjust the nut down "Only" 1/8-1/2 turn. If you operate your engine a consistent high RPM, use the lighter setting (1/8 turn).

What is 1/4 turn? (see image at right)
Well, imagine the hands on a clock. You have the obvious 12:00, 3:00, 6:00, and 9:00 settings as well as the numbers in-between those. If you start with your wrench at the 12:00 position and turn it clockwise to the 6:00 position you have just made 1/2 turn. Going from 12:00 to the 3:00 position would be 1/4 turn. What is 1/4 Turn?

Now, you will do this for all the intake valves and then do the exhaust valves the same way.

[JimM]

the problem with adjusting hydraulics with the engine off is the "spin the pushrod and feel for resistance part." This takes a "touch" that must be developed with experience. Even after near 40 years of working on engines, I've found that if I run em running, the motor runs better.

Most novices trying to spin pushrods put em way too tight.

For least mess, DO NOT REV THE ENGINE. Get it fully warm before you start turning wrenches, and adjust the idle to the lowest possible stable idle.

These things do not squirt oil 3 feet in the air at idle. It dribbles out of the pushrods, or maybe squirts up an inch and hits the stud. Rarely goes over the stud and never beyond the tip of the rocker at the valve.

As long as you don't rev the motor, any mess you get will be from the head casting filling with oil, and the oil will overflow the flange at the rear of the engine and run over at the corner onto the header.

One turn or less should be enough for you to identify an audible clack from that rocker, then tighten back down till the clack goes away plus a quarter turn and move to the next stud. Watch the oil level in the back of the head, if it gets too close to the rail you can always shut it down for a few minutes.

[cd playa]

Originally Posted by JimM

the problem with adjusting hydraulics with the engine off is the "spin the pushrod and feel for resistance part." This takes a "touch" that must be developed with experience. Even after near 40 years of working on engines, I've found that if I run em running, the motor runs better.

Most novices trying to spin pushrods put em way too tight.

For least mess, DO NOT REV THE ENGINE. Get it fully warm before you start turning wrenches, and adjust the idle to the lowest possible stable idle.

These things do not squirt oil 3 feet in the air at idle. It dribbles out of the pushrods, or maybe squirts up an inch and hits the stud. Rarely goes over the stud and never beyond the tip of the rocker at the valve.

As long as you don't rev the motor, any mess you get will be from the head casting filling with oil, and the oil will overflow the flange at the rear of the engine and run over at the corner onto the header.

One turn or less should be enough for you to identify an audible clack from that rocker, then tighten back down till the clack goes away plus a quarter turn and move to the next stud. Watch the oil level in the back of the head, if it gets too close to the rail you can always shut it down for a few minutes.

thats the way my dad and older brother did it back in the days, one person would be listening with a piece of garden hose on the rocker they were adjusting, while the other person would be wrenching.

[onovakind67]

I use the 'listen for the clacking' method, too. I set the cam in the proper position ( ICEO ) and loosen the valve adjustment until I can rattle the rocker on the tip of the valve. I tighten it until I can't rattle the rocker and hear it clack anymore, then 1/2 turn tighter. I don't mess with the pushrod at all. It shouldn't take 2 men, a hose, an extra set of valve covers, and a box of rags just to set the valves.
How much preload does 1/2 turn put on a lifter? What's the difference in preload between 1/2 and 3/4 turn? Is the preload the same if you have 1.5 rockers and 7/16" studs compares to 1.6 rockers and 3/8" studs?

[Steptoe]

Why is it deemed necessary to re-adjust them while running?

like Jim says...couple posts above...and a 2x check/ confirmation is always a good idea. just that once in while one will find 1 or several not quite right.

[onovakind67]

What does 'not quite right' mean? Is there a specific preload? How do you know what the preload is? Is there any modern cam manufacturer that recommends adjusting the lifters while the engine is running? How do the Mopar boys do it with the non-adjustable valvetrain?