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Valve adjustments Rebuilt GM 57

J

jpflhr

Member
"I just had a rebuilt 1985 5.7

"I just had a rebuilt 1985 5.7 put in and found out after installing everything that the valves need to be adjusted because of the new Hdy lifters and it also seems to be no oil pumping up thru them?. Its the older style motor were the bolts for the valve covers are on the outside rim, It looks like I can get to 3 bolts easy and 1 bolt looks like maybe a swivel socket may work?? Will the valve cover come off with the exsaust manifolds on? Is there a way I can remove the valve covers without removing the exsaust manifolds from the block? Can I just remove the center rizers and will that allow covers to be removed? Or is it best to unbolt the manifolds from the block and can I do that and have them move a little without taking the whole exsaust apart?.Also can I set the valves on a cold engine Or? What is the best way? Thanks"
 
"On my 86 350 I have to remove

"On my 86 350 I have to remove the exhaust manifolds. The covers wont pass over the rockers with the exhaust on. Adjusting the valves is a time consuming process, but easily done. Check any 350 chevy book pertaining to your year at almost any auto parts store. You have to make sure the rocker in not on a downward stroke,usually make the other rocker for the same piston go down to be sure, tighten the adjuster nut until there is no play left in the pushrod, and give it another 1/4 turn after that. Do that to all 16 rockers in sucession as you turn the motor over, by hand preferrably, but you can bump the starter as well after pulling the ignition wire. And the only way to see if oil is pumping through the rockers is to run the motor with the covers off, can be done, but quite messy unless you're using the oil deflection clips made for that type of visual inspection."
 
"John,

One more thing:

E

"John,

One more thing:

Exhaust manifolds should come off. It's much easier. Cold engine ok, but warm is better to turn the motor over. I use a 18" breaker bar attached to the crank pulley to turn the crank 1/4 turn after each adjustment. This places the next cylinder in sequence at TDC. It takes me about 45 minutes from start to finish including removing the exhaust manifolds. Good luck!

Mike"
 
"John,
The above are all good

"John,
The above are all good ways to adjust the valves.
Depending on the room I have found at times the valve covers will come off if the manifolds are just loosened up some so they will clear the valve covers.
This doen't always work but most times I've had luck doing this.

Just make sure the gaskets are still ok.

The thing that concerns me is the lack of oil pressure you said it had.

If you have no or too little oil pressure the valves will not work right.

Most rebuilders will run the oil pressure up before the engine is installed.
This is done for at least two reasons. One is to make sure the engine will have oil pressure when started. The other is so the engine does not run without oil pressure when it is started.

It's a good idea to check the oil pressure with a mechanical gauge before you do anything else. If you have at least 40 psi at 1200rpm then all should be fine. Make sure the engine is at running temp but only if it shows pressure while warming up.

Good luck."
 
"If the lifters weren't pu

"If the lifters weren't pumped up before install, they will be empty and the lash adjustment will be way off. I like to immerse each lifter in an oil bath and pump them before dropping them in the bore. Also, I'd been taught that to get the lifter plunger into the middle of it's travel, one complete revolution of the rocker nut is required after zero lash. I've had good service out of the 10-12 sbc's that I set up this way."
 
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