Small block chev help needed (305, rocker arms)
 

It's in an 89 camaro. we redid the valve stem seals, and have had issues getting the rocker arm bolts to the right torque. The manual is useless, 85 inch pounds or something dumb like that...

Either they're too loose, and make noise, or too tight and it wont run.

Please help, what's the correct way to tighten down the rocker arm nuts after replacing the valve stem seals?


Thanks for the help
~Nate

Nate:

PM me and I'll set you up with a guy in Independence that re-built my 283 Chevy SB a few years ago...his name is Steve...

You dont torque them down they are adjustable. Here is how you do it. Put the lifter on the base circle of the cam ( top dead center on compression stoke) loosen rocker so pushrod can easily turn back and forth with oily fingers. While turning the pushrod slowy tighten the rocker untill the pushrod stops turning (thats zero clearance). then tighten the rocker 1 full turn.
If you get a manual it will tell you what 8 rockers you can adjust at tdc #1 then turn the crank 1 turn and do the rest. Or you can just do one cyl at a time.

I always did mine with the engine running but you have to have the clips that keep the oil from squirting everywhere.

Tighten each one down until it just quits clicking then turn 1/4 turn, listen for the engine to bog down then smooth out, turn another 1/4 turn, wait and then a final 1/4 turn...

Yikes! I believe the above procedure is for fully pumped up lifters. If you aren't sure they are pumped up, you could put your valvetrain in a bind and break something.

Here's a better way.

On the base line, as done above, tighten the rocker until the pushrod displaces the lifter plunger to about half of its travel. To find the travel of your particular lifter, compress the piston to the bottomed out point. Then back off halfway.

USE GM EOS assembly lube on non-roller lifter engines!!!!! One 16 oz can per 5 quarts of oil. Make sure you also generously apply assembly lube to the cam lobes and lifters.

THIS IS CRITICAL!. ZDDP has all but been removed from conventional gas engine oil to protect the catcon. ZDDP is what intimately protects wiped surfaces in your engine - lifters and cam lobes. Then use DELO400 or other diesel engine oil as the lubricant. It still has a decent amount of ZDDP is it.

That's the way I've always adjusted GM rocker arms with hydraulic lifters, even without the clips. It gets a little messy but I just take the car to the car wash afterwards and spray down the engine compartment.

There is a spring inside the lifters keeping the plunger at the top. You can even use this procedure on a new lifter. One turn will put the plunger at mid travel.

I've been able to spin a pushrod all the way to the bottom. I lubed the heck out of everything. I learned from my mistakes. My way takes out any guesswork.

And these days, with the oil being sold, adjusting after start up could be disastrous.

well beings you just did valvestems seals there should be no need for a break-in oil.i usually just run the rocker nuts down til the slop is gone.start engine,tighten up the loose ones til they just quit clattering,get them all quiet,shut off engine then give em all a half turn.i never give them a full turn.

I always did the 3/4 turn past quiet while running technique. I was a teenager back then, and was not a bit concerned about the oil. It disappeared into Dad's gravel driveway pretty quickly.

Oh, my bad. Somehow I thought this was a rebuild. As RosannaAnna Danna says - Never Mind.............


But, if you could fimd an old sbc valve cover somewhere, and cut the top off, it will keep thing clean.

i've seen people do that.only problem he would have is on an 89 they used 3 bolts down thru the top of the valvecover,not the 4 bolts on the outside lip of the cover.

Yeah, they're stupid, and a ***** to work with...

What are theese clips called, the ones that keep the engine oil from squirting everywhere...

So, plan of action consists of:
Take covers off, install the clips, and loosen the tight ones, and then (when running) adjust them so they just stop making noise. Then shut it down and tighten them 1/2 turn?

Mondays the day
~Nate

Loosen all the rockers until you can spin the push rod with your fingers but not lift it up and down. Start the engine and loosen each rocker until it clicks then slowly tighten it back down until it just stops clicking. From there, with the engine still running, tighten it 1/4 turn and wait for the engine to bog down and then return to a normal speed. Repeat this two more times for a total of 3/4 turn on each rocker.

It should go like this for each rocker:

1. Loosen or tighten rocker (all of them) until you can just spin it with your fingers.
2. Start engine.
3. Loosen rocker until is starts to click.
4. Tighten rocker until it just quits clicking.
5. Turn 1/4 turn, wait for the bog and return to speed.
6. Tighten another 1/4 turn, wait for the bog and return to speed.
7. Tighten a final 1/4 turn.


Clips:

http://www.jegs.com/p/Mr.+Gasket/748856/10002/-1/10797