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Adjusting Hydraulic Lifters On Small Block Chevrolet

Install all the hydraulic lifters and pushrods.

NOTE: New lifters do not have to be pre-lubed. Assembly lube should be put on the cam and the mating face of the lifters.

Install all the rockers and the adjusting nuts leaving them loose. Do not tighten the adjusting nuts before adjusting the valves. Make sure the pushrod is in the lifter and the rocker arm seat when making the adjustments.

Adjust one valve at a time.

Rotate the engine in the normal direction of rotation (clockwise looking from the front of the engine) until the exhaust lifter on the cylinder that you are adjusting just begins to move up. At this point adjust the intake valve on that cylinder to ‘0’ lash with no pre-load. Then tighten the adjusting nut ¼ to ½ additional turns.

Rotate the engine over again until the intake lifter has come to the full lift and then is almost all the way back down. At this point adjust the exhaust valve to ‘0’ lash and then tighten an additional ¼ to ½ turns.

Continue the above for each cylinder until all the valves have been adjusted.

NOTE: Rather than spinning the pushrod and attempting to get the correct ‘feel’, I suggest holding the pushrod between two fingers and lifting the pushrod up and down while slowly tightening the adjusting nut. When you reach the point where there is no up and down movement you will be at ‘0’ lash.

The problem with spinning the pushrod and attempting to get the correct ‘feel’ is that you can and will still be able to spin the pushrod even if you bottom out the lifter. This can cause you to over tighten the adjustment and can lead to bent and / or broken pushrods and valves.

Priming the oil system before starting the engine will fill the hydraulic lifters.
 

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Good advice on the "up and down" pushrod method, rather than the "spinning" method. I found out the hard way thta the up and down method is far more accurate.

Before you do your 1/4 to 1/2 turn, you want the lifter to have no preload, but be right on the verge of being preloaded. The problem with the spinning method is you can very easily have the lifter partially preloaded, and still spin the pushrod quite easily. So unless you have a lot of experience and great feel, you can easily make the valve too tight. And all the lifters can feel and preload a bit differently, so you can have them adjusted all over the place.

With the up and down method, there is basically no chance of midadjusting, and you don't have to have any "feel" or experience at all. It is VERY obvious when the lifter stops moving up and down and you are at "0" lash.

The method described in the post above will work great, but involves a lot of turning of the engine. Not a problem when the engine is on a stand, but when it's in the car, I found a great website that described a way where you only have to turn the engine once! You find TDC compression for Cyl 1, then adjust half the valves (he described exactly which ones). Then turn the crank 360 degrees and adjust the other half.

I used that method, along with the "up and down" method, and was finally able to get my valves adjusted spot on, after trying all the other different ways (engine on and engine off) without being able to get them quite right.
 

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retired 56 said:
someone told me I could adjust my valves in my 355 chev eng. without it running. It is on eng. stand. does anyone know how to do it. hyd cam ,thank you. also the intake is still off
The way I do it is with the firing order.. bring up #1 on compression stroke TDC.. #6 will be split.

Adjust #1 and rotate the engine 90 degrees and adjust #8 just follow the firing order and rotate the engine 90 degrees after and you only have to rotate the engine 2 times.

If you understand splitting the overlap on the camshaft you can look at the firing order like this

1 8 4 3
6 8 7 2

When #6 is split then adjust # 1 and so on..
 
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