Re-installing push rods and rockers

[thebikedoctor33]

I recently bought a 75 el camino with the 350 in it. it needs tons of work and i'm on a limited budget... anyway, i took off the valve covers and decided i was going to clean up the rockers and pushrods. being the amatuer mechanic i am, i didnt look to see how many threads were showing on the studs the rockers are on or anything of that sort. after installing them, i realized all the valves were at differant heights. this makes sense obviously but how do you know how much to tighten the bolts down? specific torque? as of now they are all just loose enough so you can just barely move the rocker or the rod. what to do? also upon installin new valve cover gaskets, do i need some silicon? i got rubber ones not cork.

[AlmostStock]

You need to adjust the valves on each cylinder when it is in the firing cycle. This means both valves will be closed and the lifters will be on the cam base. Your distributor rotor will also be pointing to that cylinders plug wire. To do this turn the engine by hand with a large socket wrench on the crankshaft center bolt (remove the spark plugs first) to TDC (top dead center) on each cylinders firing stroke. Once in this position you will notice the pushrods will be low and no longer rising or lowering as you turn the motor. Most people start with #1 and the timing marks will be lined up. #6 will also have the timing marks lined up (360 degrees turn from #1) so check the distributor rotor.

Now slowly tighten the rocker stud nut as you spin the pushrod with your other hand. When you feel all play has been taken out give it 1/2 of a turn more. Then advance the motor to the next cylinder and repeat. Each cylinders TDC will be 1/4 crank turn from the last. The Chevy firing order is 1,8,4,3,6,5,7,2 and the cylinders are numbered driver side front to rear (1,3,5,7) and passenger side (2,4,6,8). Since you already tightened your rockers down some, you should first back them all off several turns before starting.

The gaskets you got are the better ones. I like to use gasket cement to attach them to the valve covers and nothing on the other side. This makes future service or adjustments clean and handy.

[thebikedoctor33]

thanks for the rapid reply... doesnt sound too complicated... but how do i locate the crankshaft center bolt. i'm guessing thats behind the timing cover?

[public]

The crankshaft center bolt is in the center of the bottom pulley, removing sparkplugs will make turning it a lot easier. MARK YOUR PLUG WIRES WITH THE CYLINDER NUMBERS!! If your belts are good and tight it may be easier to turn the engine via the Alt pulley. Good Luck.