SBC - adjusting rockers with engine running

OK, sbc 327 in my rod.....a rocker is clattering a bit so it's time to adjust them all. I'm planning to do it with the engine running. I plan to systematically (how? who the hell knows, but it sounds good) back off the nut on a rocker til it clatters (unless it's clattering already), then slowly tighten til the clattering stops, then give it another 1/2 turn.

I'm hoping that I won't be splattered with the slippery stuff, but a little preservation oil can't hurt this old goat, right?

Anywho, does this sound right to you engine guru's? Is this how you guys do it?

 

That's how you do it alright.
Grab an old pair of valve covers and cut the top open just enough to get a socket in the. No oil spraying everywhere.....

 

you can buy some little clips so you dont get sprayed with oil.

 

When we did it that way, we cut a slot in an old valve cover directly over the adjusting nuts and installed it. This allowed us to somewhat control the oil spray. Otherwise it gets messy real quick.

 

I'd rather do it engine off but that said, find a valve cover and cut a strip out of the top to allow access. Saves a ton of cleanup.

If you want to do it engine off there are several accurate ways. The easiest is to have a bar on the crank bolt. Slowly rotate the engine (plugs out makes it easier) until the exhaust valve starts to move, adjust the intake. Turn the engine (in normal direction) until the intake closes, adjust exhaust.

 

^^^^^
x2, this way you can take your time and not make a mess.

 

the other day I adjusted the valves that way (running) and the 1/2 turn was too much, I could not turn them down more than 1/4 turn after the noise stopped without killing that cylinder. So I just left them the 1/4 turn ...so far , so good.

 

I like the little clips, they divert the oil, even an old valve cover that oil seems to know how to spray you!
They just don't cost very much.

 

What are these "little clips" you speak of?

 

There used to be, maybe 30 odd years ago, an ad on TV for oil or filters or something that featured singing rocker arms!

Approxilutely so:
"We are the rocker arm as--sem--ba--lee
The rocker arm as--sem--ba--lee
The rocker arm as--sem--ba--leeee
And we don't like dirt!!"
(repeat until wife dials 911)

I always sing that when adjusting a running Chevy.
Adds lots of precision and style to the process.

 

ive used a vacuum guage as well , while adjusting when running

 

Mr. Gasket, around 10 bucks search: Rocker Arm Clips, Oil Deflecting

 

You're off the hook, Bruce! lol.

 

As everyone else mentioned, an old set of valve covers with the center cut out works real well for containing the mess...and there will be a mess...and, only 1/4 turn not 1/2 turn. I've used this same method since the 60's and it's never failed me. Doing it static as per hoop98 is the cleanest way, but also much more time consuming. Your call.

 

Thanks for the old valve cover trick tip, dudes. I have an old one that I will sacrifice for this daredevil stunt.

 

1/4 turn after the clatter sound is the way to go, 1/2 turn is usually a little more than you need.

 

As most everyone else has said it's a messy thing to do but it works. I found that it helps to turn the nut slowly to keep the engine from stalling. Most of my experience comes from a Pontiac engine; they have the same type of rocker arm as--sem--ba--leee.

 

Not very messy with the clips and 1/2 valve cover. Minimal I'd say.
No clips and you are likely to cover everything.
No valve cover and you'll be dropping oil on the headers.

 

One turn is the factory adjustment to center the plunger in it's travel. Using less pre-load (1/4 or 1/2) has been a way to minimize lifter pump-up. I'd go with 1/2 unless you have noise afterwards.

 

I fail to understand how one can do a static tune on hydraulic lifters. Solids, sure. Hydraulics need, well they need hydraulics: oil pressure. Running tune for hydraulics, static for solid lifters.

 

If you do it this way make sure engine is cold and you will need to spin the pushrod with your fingertips until you will feel a slight resistance in the pushrod when you have taken up all of the clearance. This is “zero lash.” Turn the adjusting nut to the specified pre-load – typically 1/4-3/4 of a turn, but this will vary based on the lifter number.

 

I used to do it with the valve cover, and the clips, and the oily mess from not using either. One day a friend was watching me, and when I was done, he had this big smail on his face....


He went and loosened every valve when I went and was washing my hands. I said WTF. He said, let me show you how to do this right.....


AT the point of the intake valve opening, he would take that cylinder exhaust valve pushrod spin it in his figners as he tightened the rocker. He also checked uop and down. AT the very point of no play or gap, he then turned the rocker nut another 1/2 turn, and moved on.....

His way made no mess, he is a GM tech. I then did it, and really liked it. But I had the advantage of a tech there showing me, not a guy typing it on the internet....

You may try youtube..... I will never go back to the clips or the valve cover method.

Bobby typed faster.... But that's the method I like alot

 

That's the way I've always done it with hydraulic lifters.

 

The radiator cooling fan spinning also causes a lot of oil to be thrown about due to turbulence, remove the fan belt but watch for overheating. After adjusting the lifters to stop them from "clacking", you wait a few seconds, then finish tightening them down a quarter turn at a time, waiting a few seconds between quarter turns for the engine to smooth out. I've had my valve adjusting, modified valve cover, for about 45 years now. I also have the clips, but prefer the valve cover method. No matter which way you go, there's going to be some oil splashed/throw about. Butch/56sedandelivery.

 

The reason 1/2 turn kills the cylinder is because it takes the lifter a few seconds to bleed down. The valve doesn't close all the way for that short time. You have to give it some time to smooth out. Anywhere from 1/2 to 1 full turn will work.

 

You can static adjust hydraulics, it's very easy with the intake off.
You can measure the lifter preload and off you go exact as you can measure.
Just like lash only different.


I've never measured the thread pitch on the rocker studs and don't know the exact dimension of preload a 1/2 turn on the nut will give you?

Some engines do not give you the luxury on lifters.
Bolt them down and you are done.

 

Building these units for a living, we've adjusted maybe 1000's of the SBC/BBC hydraulic lifters and have never had to have the engine running.

It isn't necessary and it is much neater. All pushrods/rockers must be backed off beforehand. If this a new build you start with the 2 rockers on #1 cylinder first! (We are talking SB/BB Chev's here)

(Add) Intake on or off doesn't matter, it is easier to "see" having it off however!

It does require an oil-priming tool, we use an old distributor, and proceed to set them on the engine stand. Never a single issue! We use the firing order and by the time the crank makes 2 turns all 16 valves are set! Simple, doesn't get any easier? (We aren't talking "all-out" race cams here but most hi-perf deals!)

Thanks, Gary in N.Y.

P.S. The adjusting nuts (7/16-20) give you .025" per 1/2 turn. This is the normal setting we use with the "Johnson" tappets. You can run a 1/4 turn but we feel this isn't quite enough when you consider "temperature" changes (expansion and contraction) during normal operating conditions.

 

also always better a little loose than a little tight...I had roller tip rockers that inherently clicked due to their design, I put a little more on it to get the click out, car ran like poop, readjusted and ran fine..just make sure it is adjusted correctly....you can get it in the ballpark prerun adjustment but for hydraulic, really needs to be running to get it right as others mentioned

 

In high school (1968), I blew the head gaskets on my ’62 Fairlane, my dad brought home some tools and said, “Well, fix it.” I took it apart, had the heads milled and put it back together. After a few hours of cranking on it, my dad came out and told me to adjust the valves to 1/4 not 3/4 turn as the book said and set the ignition timing as close as I could to factory. About an hour later I had it fired. He then came back out and showed me how to find the best ignition timing. He was a true “Tune it by ear”, kind of guy. (I figured out later that even 1/16 over the factory 3/4 turn on my sbf would cause a problem.)

If memory serves me the factory said to set the valves at 3/4 in my 221 cube v8. As a test, I did this once, as well as factory ignition timing. It ran just like it should. My grandmother would have cruised to the market in style. But with only a 1/4 turn on the valves and an advanced ignition timing, it was a lot crisper and way more fun to drive.

I always liked tuning a running motor. Do it enough on the same motor and you can hear when the power is balanced and it sounds just right.

As for the oil spraying, I say just drain the oil pan, tune fast and buy a pressure washer.

 

I remember that. I still sing it too. I think it was Mobil.