Valve adjustment SBC

[ClassicGuy]

Ok Gents,
I have a SB 350 with hydraulic lifters and I'm replaing the stock rocker arms with steel roller rockers. Do I need to torque the rockers to a certain level or is there a different way? I have never done this and want to learn on my own so any advice would be very much appreciated.
Thank you.
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[oklalawnboy]

Originally Posted by ClassicGuy

Ok Gents,
I have a SB 350 with hydraulic lifters and I'm replaing the stock rocker arms with steel roller rockers. Do I need to torque the rockers to a certain level or is there a different way? I have never done this and want to learn on my own so any advice would be very much appreciated.
Thank you.
Posted via Mobile Device

My 2 cents. You have to make sure the valve your working on is in the closed position. I spin/turn the push rod (thing that sits in the seat opposite the roller tip) with one hand while tightening the new lock nut. When the pushrod quits spinning freely I tighten the nut a half turn more and stop. The go to next closed valve and repeat. You'll have to "feel" when the pushrod quits being easy to spin. Or the older way and tighten them down while the truck is running and they quit clacking. Can be messy if you don't have clips to deflect the oil back into the head. Good Luck.

[ClassicGuy]

Thanks for the help, Sounds pretty strait forward.
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[truckster]

Here's a good tutorial:

http://www.hotrodders.com/forum/smal...nt-206144.html

[GMCJOE]

You adjust the hydraulic the same as you would a flat tappet. The only difference is that you give them a 1/4 turn preload after you get zero lash on the push rod. It is recommended that you only do an 1/8 of turn if you are going to be running high rpm's more often than not, more towards a race application than street application.

This link says to do it after the engine has been running, but you will be fine doing it with out running the engine. Though most of the time it is recommend to do readjustment after you break the cam in after running the engine at 2500 rpm's for 15 minutes. This is one of the better break downs of the adjustment I have found that explains pretty in-depth about it.

http://www.centuryperformance.com/va...procedure.html

I suggest just doing the 1/4 turn for preload after zero lash. It has worked just fine for me thru out the years of doing this with no failer.

[68Gold/white]

Not knocking anyone, but I've never got the pushrod spinning method to work...however...

It's a simple deal. The lifter HAS to be on the base of the cam, NOT on the lobe, when cam lobe is pushing the lifter up to open the valve.
Tighten the rocker down until there is NO clearance or jiggle between the rocker and top of the valve stem. Then tighten the rocker nut another 1/4-2/2 turn. That's it....You just have to make sure you are NOT campressing the plunger in the lifter, when taking up the clearance out of the rocker/valve area...

[GASoline71]

1/4 turn is for a higher lift radical cam. Stock is one full turn. Depending on your cam I'd say 1/2 to 3/4 turn.

Personally I've always used 1/2 turn on my performance engines, and 3/4 turn on a more mild stockish build.

Gary

[cdowns]

i'd think if you never done it and dont have engine experience a service manual might b a good investment for you or at the very least a daytrip to the library

[yuccales]

If you like wrenching on small blocks, this is a good book to have, "How to rebuild your Small Block Chevy" by Dave Vizard. It's got some good info.

[GASoline71]

Originally Posted by cdowns

i'd think if you never done it and dont have engine experience a service manual might b a good investment for you or at the very least a daytrip to the library

Couldn't agree more. It always makes me wonder why cats that own 40 year old vehicles don't have the basics like a service manual. I actually own some sort of service manual for every single car or truck I own.

Gary

[68Gold/white]

Originally Posted by GASoline71

Couldn't agree more. It always makes me wonder why cats that own 40 year old vehicles don't have the basics like a service manual. I actually own some sort of service manual for every single car or truck I own.

Gary

A lot of the best info and details are not always in books.... I've been blessed to have as friends a REAL engine builder, and a REAL machinist, and my Dad was a mechanic before he retired....

AND when I was younger, a couple of my buddies built several engines... I got to learn from their mistakes...

Most of the stuff (my opinion) on 40+ year old cars, mechanically is visual stuff, brakes, suspension, even electrical, you can see what you are working on, and don't have to visualize what the problem might be, you can see it, NOT so w/ modern computer cars........