Valve Lash Adjustment

[pontiacgp]

I didn't find it to be extra work, I used the GM procedure for roller cams and with that method the engine was rotated 90 degree increments 8 times which is the same as this method. I found this method easier since I did not have to reference any material to adjust the proper rocker. I don't use the running method, especially with roller lifters.

 

[Bonnewagon]

I think it is a super easy method for a dry motor with no intake in place. With an intake there is very little room to spin a push rod but I guess it can be done. What about a motor that has oil in the lifters already? Does that matter?

 

[pontiacgp]

I think it is a super easy method for a dry motor with no intake in place. With an intake there is very little room to spin a push rod but I guess it can be done. What about a motor that has oil in the lifters already? Does that matter?

Oil should not matter since you only going for a zero lash adjustment. If you have poly locks you can tighten it by hand so it makes it easy to feel when you have zero lash. I was easy with the manifold off so you can see more but that method would work with the manifold on.

 

[Bonnewagon]

Yeah but he made a big point about a lifter being full of oil not adjusting right. I'm confused. If a lifter is empty, then you are compressing the internal spring a bit, right? Or not? And if a lifter is full of oil it will not compress at all. He said that is the wrong way. So on an empty lifter are you compressing the spring all the way until the push rod binds? And that gets the .035" ? Or just until it won't be loose? I gotta watch that again.......

 

[Bonnewagon]

See minute 3:20 to 4:25. He wants the lifter spring depressed .030-.035" and you can't do that if it has oil in it.

 

[pontiacgp]

Mark, I like to see how he gauges 30 to 35 thou. With a 24 pitch thread you get .041 for each revolution so if you want you can get zero lash without setting the lifter 30 to 35 and do an extra 2/3 turn on the preload. When I was looking to see what the preload is for my set up I read from no preload to 1 full turn. I ignored the 30 to 35 setting, set it to zero lash and then 1/2 turn to preload it and it ran great with no more noise than you get with a roller engine. I have the same cam as a ZZ4 engine and read that those engines are noisy cause art factory they set the valve lash to zero and leave it like that. I have heard a new ZZ4 engine and they are noisy, more than I like. The 604 crate that we had in our circle cars have the same cam as the ZZ4 but were never noisy like the ZZ4

 

[Bonnewagon]

Steve I agree with your method and I am sure it works perfect. But on any motor you have only one opportunity to do that on dry lifters. Once it starts you now have oil filled lifters forever. Maybe he should have said this only works on fresh lifters? I absolutely hate adjusting poly-locks on a running motor. But what else can you do? If you adjust for zero lash on a filled lifter, then add whatever extra turn for pre-load, when the motor starts the lifter will open the valves too much until a couple of cycles pass when it can bleed down and self adjust. That gets you the crappy running he spoke of. So I guess that this is a great way to adjust a dry motor but he should have mentioned that it HAS to be a dry motor.

 

[pagrunt]

If it's worth anything the shop I delt with suggested to gap the rocker at the valve at .002 with the lifters dry. This was for non roller lifters.

 

[pontiacgp]

Mark, with a roller cam it is risky to adjust them on a running engine

 

[Wraith]

I still adjust on a running engine due to oiling/pumped up lifters and I'll be the guy that bought the brand new ZZ4 that wasn't noisy. 😗