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-   -   adjusting rocker arms (https://67-72chevytrucks.com/vboard/showthread.php?t=456804)

baller5040 04-02-2011 03:10 AM

adjusting rocker arms
 
I have looked all over the place to find out how the rocker arms should be adjusted so they will work properly. Anyone know of any good posts or pages that might explain how to do this in good detail even with pictures would help too so i know what i am looking for and looking at.

ppbr2001 04-02-2011 04:42 PM

Re: adjusting rocker arms
 
With the motor running and valve covers off, loosen until you hear them clack, tighten until it stops and SLOOOOOWLY give it a quarter turn more.

orbot 04-02-2011 05:11 PM

Re: adjusting rocker arms
 
I have never been able to do this, always take the truck to the shop...then again im not a patient person. just be carefull not to overtighten then you will bend the pushrods

85Bowtie 04-02-2011 05:27 PM

Re: adjusting rocker arms
 
I've never adjusted them on a Chevy, only Mopars. Mopars are usually non-adjustable, they're shaft mounted and you just bolt them down. However...

I have had to use adjustable rockers on 440's before after chopping the deck because of poor availability of pushrods. The first thing I do is take a tupper ware container or anything tall enough for a lifter and fill it with oil. Then I take the lifter and stand it up in the container and "pump it" with the pushrod until all the air bubbles come out. After I do all of them, I slide them in the bores and drop the pushrods in. Then I'll take the shaft with the adjusters all the way out and assemble the rocker assembly. Then I take the first cylinder and bring the crank around until both lifters are down (both valves would be closed). I set the pushrod in place correctly and adjust the rocker until the pushrod JUST begins to plunge the lifter, then go about an 1/8th turn. There usually should be just a few threads from the adjuster below the rocker arm and if you have correct length pushrods there should be no clearance/geometry issues between the pushrod and the rocker. Tighten the lock nut down and then I proceed to the next etc...

I know they have specs to set up your rockers at, but I've never had an issue doing it this way. The only difference is the Mopar shaft mounted set up gives you a more stable valvetrain so there may be some forgiving in using this method.

I've never been a fan of running any engine without valve covers on it, that sounds stupid to me, kind of like you're playing Beat the Clock. $.02

1LowToy 04-02-2011 05:59 PM

Re: adjusting rocker arms
 
That's why you snag and old set of valve covers and cut the top off the cover. Oil won't go flying around then. Post #2 ppbr2001 is correct on the adjustment.

3r!c84 04-02-2011 06:00 PM

Re: adjusting rocker arms
 
stock rockers? or rollor rockers with locking nuts?

dmsz28 04-03-2011 10:52 AM

Re: adjusting rocker arms
 
Quote:

Originally Posted by 1LowToy (Post 4595839)
That's why you snag and old set of valve covers and cut the top off the cover. Oil won't go flying around then. Post #2 ppbr2001 is correct on the adjustment.

That is the worst way to adjust your valves. Why would you ever do that?? Adjustment depends on if you're running a hydraulic or a solid lift cam. The easy way to do this is to set valves is start with setting the #1 cyinder on TDC on the compression stroke. Then set both the intake and exhaust valves at the same time. Then turn the crank 90* then set the next set of vavles on the next cylinder in the firing order. Go through the firing order untill you're done.

when setting solid lift cam, set lash to what the cam manufacturer recommends
when setting hydraulic lif cam, set plunger preload usually .040-.075 which is roughly 3/4 turn past zero lash.


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