Adjusting roller rockers - The 1947 - Present Chevrolet & GMC Truck Message Board Network

customizer76 · 02-03-2011, 12:37 PM

I know there are different methods of adjusting the rockers in the sbc, but the real question is. Which of the two is better with the engine running or with the engine off? I have completed them before both ways but I was told with the aluminum heads I should do them with the engine off. What is your take on this matter?

3r!c84 · 02-03-2011, 01:20 PM

Quote:

Originally Posted by customizer76

I know there are different methods of adjusting the rockers in the sbc, but the real question is. Which of the two is better with the engine running or with the engine off? I have completed them before both ways but I was told with the aluminum heads I should do them with the engine off. What is your take on this matter?

motor off. twist push rod till it starts to get hard to turn. go another 1 full turn on the bolt and tighten down the retainer.

3r!c84 · 02-03-2011, 01:23 PM

good info

YouTube - How to Properly Adjust Valves on...

customizer76 · 02-03-2011, 03:36 PM

Thanks for the info.

draggin86 · 02-03-2011, 04:54 PM

Great video! thanks for posting!

faribran · 02-03-2011, 05:04 PM

i agree.. with motor OFF.. another tip.. make sure you have the LOCK secured, after the adjustment is made......... i have seen this come "unlocked"

Dru · 02-04-2011, 01:52 AM

OMFG...that guy in the video needs slapped. I hate misinformation.

Your cam will come with instructions, most are NOT a full turn, only 1/2-3/4 after 0 lash. You go not get any benefit from tightening them more, and can possibly cause damage in some cases.

Also most Haynes, and motor manuals will tell a procedure to adjust the valves with only rotating the engine to TDC, then half over. With the engine off. I prefer doing them one by one, but the other method is fine too.

BigBlocksRule · 02-04-2011, 08:40 AM

The "twist 'em till you feel resistance" is bunk. Many will spin freely when the lifter is completely bottomed out and if there's plenty of oil in the rocker cup and lifter, you won't be able to tell when you're at zero.
Grab the pushrod between thumb and fingers and wiggle it UP and DOWN until you can feel all the slack gone. Do it a few times until you get the hang of it. Then adjust to your desired preload, 1/2 or 3/4 turn. When setting polylocks, back off from preload about 1/8 turn, tighten the allen set in the center of the polylock as tight as you can get it and then TURN THE ALLEN WRENCH AND WRENCH YOU'RE USING ON THE POLYLOCK AT THE SAME TIME until they're TIGHT. This is the only reliable way to lock 'em down. If you simply try to tighten the allen set down after setting preload, it will get loose again. That's a promise.
Make sure your rocker studs are perfectly flat on top. If they're not, the allen set can't tighten squarely and they'll work their way loose.

02-03-2011, 12:37 PM	#1
customizer76 Registered User Join Date: Nov 2009 Location: Virginia Posts: 26	Adjusting roller rockers I know there are different methods of adjusting the rockers in the sbc, but the real question is. Which of the two is better with the engine running or with the engine off? I have completed them before both ways but I was told with the aluminum heads I should do them with the engine off. What is your take on this matter?

02-03-2011, 03:36 PM	#4
customizer76 Registered User Join Date: Nov 2009 Location: Virginia Posts: 26	Re: Adjusting roller rockers Thanks for the info.

02-03-2011, 04:54 PM	#5
draggin86 Registered User Join Date: Aug 2004 Location: Folsom, Ca Posts: 573	Re: Adjusting roller rockers Great video! thanks for posting! __________________ My build thread. Boy what did i get myself into!

02-03-2011, 05:04 PM	#6
faribran Registered User Join Date: Jul 2005 Location: AL Posts: 1,828	Re: Adjusting roller rockers i agree.. with motor OFF.. another tip.. make sure you have the LOCK secured, after the adjustment is made......... i have seen this come "unlocked" __________________ "

02-04-2011, 01:52 AM	#7
Dru Registered User Join Date: Oct 2010 Location: Wichita, Ks. Posts: 89	Re: Adjusting roller rockers OMFG...that guy in the video needs slapped. I hate misinformation. Your cam will come with instructions, most are NOT a full turn, only 1/2-3/4 after 0 lash. You go not get any benefit from tightening them more, and can possibly cause damage in some cases. Also most Haynes, and motor manuals will tell a procedure to adjust the valves with only rotating the engine to TDC, then half over. With the engine off. I prefer doing them one by one, but the other method is fine too.

02-04-2011, 08:40 AM	#8
BigBlocksRule Registered User Join Date: Jun 2008 Location: Lubbock, TX Posts: 2,047	Re: Adjusting roller rockers The "twist 'em till you feel resistance" is bunk. Many will spin freely when the lifter is completely bottomed out and if there's plenty of oil in the rocker cup and lifter, you won't be able to tell when you're at zero. Grab the pushrod between thumb and fingers and wiggle it UP and DOWN until you can feel all the slack gone. Do it a few times until you get the hang of it. Then adjust to your desired preload, 1/2 or 3/4 turn. When setting polylocks, back off from preload about 1/8 turn, tighten the allen set in the center of the polylock as tight as you can get it and then TURN THE ALLEN WRENCH AND WRENCH YOU'RE USING ON THE POLYLOCK AT THE SAME TIME until they're TIGHT. This is the only reliable way to lock 'em down. If you simply try to tighten the allen set down after setting preload, it will get loose again. That's a promise. Make sure your rocker studs are perfectly flat on top. If they're not, the allen set can't tighten squarely and they'll work their way loose.



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