B4C

I just put the heads back on my car('94 LT1 Camaro). I followed these directions on adjusting the valves I found:

"To adjust your rockers. Turn the crankshaft clockwise until the cast arrow on the crankshaft hub is in the 12 o’ clock position and number 1 cylinder is at TDC. Watch number 1 cylinder valves as the crankshaft hub arrow approaches 12 o’ clock position. If a rocker moves as the arrow moves to position, the engine is in the number 6 firing position. The crankshaft must then be turned one more time to reach cylinder number 1 firing position.
At this position, exhaust rockers 1, 3, 4, and 8 can be adjusted as can intake rockers 1, 2, 5, and 7. While spinning the pushrod with your fingertips, tighten the rocker down until you feel resistance in the pushrod - this is zero lash. Tighten the adjusting nut on the rocker arm an additional 1/2 - 1 turn.
Turn the crank 360 degrees (clockwise) until the crankshaft hub is at 12 o’ clock again. Adjust exhaust rocker 2, 5, 6, and 7 and intake rockers 3, 4, 6, and 8 as you did in the step above."

I drove the car last night for the first time. I took it easy on it. It ran good, but I could hear, just barely, some valve clatter and it sounds like one of the rocker arms on the pass side is making a little more noise than the rest. A louder swishing sound. Is there a more precise way to adj the valves(ie feeler gauge)?

EliteZ

Nope, Hydraulic roller. If u can hear chatter, just means one is lose. go back through that one, and check. Best way to adjust is Within pair of valves (intake and exhaust) if the exhaust is all the way down than adjust that intake valve and visa versa. I am pretty sure thats the best accurate way w/o fueler guages, since lifters are spring loaded u can overtighten them. make sure when u tighten them there should be slight movement when pushing on head of rocker. There are prob other ways, but thats the best IMO.

F*r*a*n*k*e*i

To adjust hydraulic rockers, it goes like this.

- Put the motor at TDC
- Adjust both valves on cylinder 1 with a box wrech. Just tighten the nut until the pushrod can barely rotate between your finger tips. Then crank it down 1/2 turn more. That should load up the spring about 0.025", which is ideal.
- Roll the engine 1/4 turn.
- Adjust cylinder 8 the same way

The order is 1, 8, 4, 3, 6, 5, 7, 2 with all 1/4 turns in between. To check you're at the proper cylinder for adjustment, cylinders 6, 5, 7, 2, 1, 8, 4, 3 will have an exhaust valve rocking when adjusting the coresponding valves in the sequence above. i.e. if you're adjusting cylinder 1, cylinder 6's exhaust valve should be starting to rock. It's even easier if you have the intake off because you can watch the lifter

Hope that helps!

myltwon

Adjusting Valves and Zero Lash



Zero lash is when you go from having slack between the lifter, pushrod and rocker arm, to the exact point of no slack. The lifter needs to be on the base of the lobe when setting valve lash. When a cylinder is at TDC, both lifters should be at the bottom of their travel (base of the cam lobe).

Gauging zero lash by hand is not an exact science. When setting the valve lash with the engine not running, you can get close enough by doing the "spin the pushrod" method. Loosen the rocker arm until you can feel slack in the pushrod to rocker arm. Spin the pushrod with your fingers while tighening the rocker arm back down. When you BEGIN to feel drag while spinning the pushrod, you are at zero lash. Once zero lash is reached, stop and add your preload. DO NOT go back and try to feel the adjustment. The lifter will immediately begin to bleed down a little. Tension on the pushrod will relax and this will make it seem like your adjustment did not work. If you want to recheck zero lash, you must loosen the rocker arm nut and tighten it down again while spinning the pushrod as before. At that point you want to set the preload and LEAVE IT ALONE.
The hydraulic lifter has an internal plunger that has a specific amount of travel. On stock engines, the purpose of preload is to compress the plunger so the pushrod will be centered within that travel. With stock lifters, turning the rocker nut another 1/2 to 3/4 turn, will normally put you in the ballpark for quiet operation without being too tight. Specific lifters like the Comp Cams "Comp R's", have less internal travel. 1/4 turn preload is more than plenty, with 1/8 or just barely any preload being better for high revving engines. Comp actually recommends .002-.004 preload on a warm engine.

Consequences of improper adjustment:
Too tight - the valves will not completely close and you will lose compression. The engine will run rough, if it will run at all.
Too loose - the rocker arms will make noise from the slack and pushrods could be dislodged. Possible damage could occur from either extreme.



Engine Running Method

Some like to adjust the rockers while the car is idling. If you wish to do this, loosen one rocker at a time until you can hear it click. Tighten the nut, but don't exert downward pressure on the rocker arm with your socket. At the point when audible clicking is gone, tighten the nut another 1/4 turn for your preload (Comp R lifters, less as noted above).



Engine Not Running Methods
There are several methods for setting the lash with the engine not running and are listed below. Read through them all. You might prefer one method over another. They all accomplish the same thing.




Method 1

If you have never had the crank hub off (or know for sure that it's orientation is correct), you can use the arrow that is on the balancer to tell you where you are. You don't have to spin the crank every 90º with this method.
When the arrow is at 12 o'clock you will be at either #1 or #6 TDC. You might have trouble identifying whether #1 or #6 is at TDC when the crank arrow is at 12 o'clock. Probably the easiest way is to look over the other valves or lifter positions. Compare them to the charts below, showing which can be adjusted. Any valve that can be adjusted should be UP (closed) and the lifter/pushrod should be down. Valves that are not to be adjusted will be in varying degrees of being open or DOWN (lifters/pushrods UP). I used to recommend looking at the valves on the #1 and #6 cylinders, but sometimes it can be difficult to tell by those cylinders only. After looking at the charts below and your valves or lifters/pushrods, you should have it figured out rather quickly.




Valvetrain Movement Reference Diagram

When at #1 TDC you can adjust the following valves:

Intake: 1, 2, 5, 7
Exhaust: 1, 3, 4, 8

Rotate the crank one revolution until the pointer is again at 12 o'clock. This will let you adjust the remainder of the valves. If you did #1 the previous time, you should be now at #6 TDC.

When at #6 TDC you can adjust the following valves:

Intake: 3, 4, 6, 8
Exhaust: 2, 5, 6, 7




Method 2


If you want to set the lash by bringing each cylinder to TDC, watch the valves and the pointer on the balancer and follow the Firing order:

1-8-4-3
6-5-7-2
Adjust both intake and exhaust of the cylinder that is at TDC. You will have to make 2 revolutions of the crank, stopping at 1/4 (90º) turn intervals for each cylinder.



Method 3


Another cylinder by cylinder method that does not require looking at the balancer position, follows:

(A remote starter switch is quite helpful)

Turn the engine in the normal direction of rotation until the exhaust lifter for the cylinder you are adjusting starts to move up.
On the intake rocker arm, adjust for zero lash and add your desired preload.
Turn the engine over again until the intake valve on the same cylinder opens completely and then is almost all the way back up.
Now, adjust the rocker arm for the exhaust valve on that cylinder to zero lash and add your desired preload.
Continue the above procedure for each cylinder until all valves are adjusted to the same amount of preload. This procedure will work for any hydraulic lifter cam with adjustable rocker arms.

F*r*a*n*k*e*i

That said, I have a set of old school valve covers that I've modified (cut the tops off of) to do running valve adjustments without getting oil all over you.

HerHotRod

They forgot to tell you one of the consequences of overtightening, you'll also round the lobes on you cam . It's happened to me by taking it to someone who thought they knew what they were doing. It cost me my hydrolic roller cam, lifters, rods, and rockers. I could have had a few collapsed lifters, but I have a hard time believing it was that many. You should have seen the cam.

Since then I've done it myself and used the cardboard flaps of a box and pushed them down along the head to keep the oil from spraying everywhere. Works good if you don't have the covers like Frank mentioned.

B4C

Thanks. HerHotRod makes me a little nervous though.
Frank, If I tear it up, I will do it your way with the cut valve covers next round.
I drove it last night, easy again, and everything felt and sounded fine. I am just keep my fingers crossed til the first time I really flog it.

plan Z

first time i did it by the book, second time did it with the engine running and liked it better that way. guess its just personal choice though.

HybridSS

glad I have solid lifters and shaft mount rockers. Makes valve lash easy to adjust.

Gunslinger09

It has to be easy to adjust Al. With that solid roler cam you will be adjusting the lash constantly.