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351W roller rockers valve adjustment

9652 Views 4 Replies 3 Participants Last post by  whisperer
Is the time for me to readjust the roller rockers on my '69 351W Are we using still same adjustement as described bellow (zero lash) or what is the best adjustement.

Loosen ALL the rocker nuts a few turns. Start with #1 cylinder, rotate the engine until the balancer reads TDC on the compression stroke (that is the next TDC rotation AFTER the intake valve opens) Grab the pushrod between your thumb and first finger and rotate it as you tighten the adjusting nut until you feel the rotating pushrod get tight. You want to achieve zero lash and stop turning the nut as soon as the pushrod just gets a bit tight. Do not tighten it so it compresses the piston in the lifter. Then add 1/2 to 3/4 of a turn (use the 3/4 if you don't want to ever have to open up the engine and do this again) Then do the same on the next valve in line on the same cylinder. Then rotate the engine until the next cylinder is at TDC on the compression stroke. repeat the above procedure for the rest of the engine, just going down the rows one at a time. The entire job takes about 15 minutes.
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That will certainly work, but it's complicated and a PITA. That's the way I do it on the stand when building a new engine before it fires.

I always adjust while the engine is idling once the engine is up and running. These are hydraulic lifters right? It's best to cut the top out of an old valve cover and install it finger tight to avoid loosing oil all over the side of the engine.

With the engine warmed up and idling just loosen each poly lock and back the adjustment off untill it starts to click. Then slowly tighten it back down untill the click just stops. Then give it about 1/2 of a turn and lock the poly lock. Move on down the line untill they are all done and then do the other side.
"It's best to cut the top out of an old valve cover and install it finger tight to avoid loosing oil all over the side of the engine. "

That's tough to do with roller rockers. I have a valve cover that I use just for adjusting valves (top cut out) and tried like hell to bend it to accomodate my roller rockers, but by the time you can access the first and last rocker in each bank, there wouldn't be enough valve cover left to retain any oil.

I just use the valve cover for the engines with rail rockers, and adjust the roller rockers with the engine off, starting at #1 with #1 at TDC of compression stroke, then going through the firing order, rotating the crank 90 degrees between each set of rockers.
Thanx, guys for the info. Just need it to refresh.
Guess I should have said "cut the top out of an old used tall valve cover"............ *G*.
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