I'm in the middle of my cam swap and I'm trying to install the new LS7 lifters, trickflow 7.150" pushrods, and 1.6 pro mag roller rockers. I went to TDC on cylinder 1 and tightened the rocker nut until the pushrod slack is gone. I then tried to go antother 1/2 turn. The nut will not tighten another 1/2 turn. It appears that some of the lifter plungers are stuck. The plunger will not move down. Some of the lifters are ok and have plenty of give in the plunger while others dont seem to budge. How can I adjust the rockers for zero lash if I can't tightening them anymore? How can I unstick a stuck lifter?

I currently have them soaking in oil but that is not helping. I also pulled the clip off one of them to see why it is stuck. It is so tight I'm not sure if I can get the clip back on. Any ideas?

I really need to get this all back together by Monday.

Thanks

 

May sound overly simple but the set screw in the polylock is backed out far enough right???

If you bottom out the plunger it should start opening the valve, not stop turning.

"stuck lifters, or collapsed" are terms thrown around about 100 times more often than it actually happens.

Is there some reason you are not just reusing the stock lifters???

 

I'm actually trying to push in the plunger with a pushrod in my hand. I also tried putting one end of the pushrod on the ground and putting all my weight on the lifter. One easily moves in a 1/4 of an inch with little pressure. The rest are stuck.

I'm doing this with a cam swap. I am using all upgraded valve train parts.

 

They are just pumped up, that's all. Normal.

 

Check the stock lifters to see if they act the same.

I have always reused the stock lifters.

My definition of "upgrade" is different then most.

 

As mentioned, they are just pumped up... Ignore it and adjust the valves the extra 1/2 turn, regardless if the lifter goes down or the valve opens... Once you start the motor they will all 'act' normal and move the way they should...

 

Damn, I wish I would have caught your posts earlier. Here's what I just posted on another forum about what I discovered today.

Ok, I think I have it figured out. Based on what many have said I was probably way over complicating things. When I went to tighten the first two rocker arm nuts I was comparing the two together and how the lifters reacted to the tightening. One was very easy to tighten even for the half past zero lash. The other was extremely hard to tighten almost to the point where it would not go half past. I had pulled both lifters out and the one that was easy to tighten was also easy to push the plunger in. It went in 1/4". I thought the plunger on the other lifter was stuck because it would not move in at all. I checked all 14 other lifters and their plungers also could not be pushed it. I tried with the old pushrod against a brick wall while putting all my weight behind the lifter. I went to two dealerships. One had 10 lifters and 4 of those pushed in 1/4" and the others appeard to be also be stuck. I went to another dealership that had 6 lifters. All of those would not push in. When I got home I checked the stock lifters and those plungers also could not be pushed in. So I had now checked 48 lifters and out of those only 5 plungers could be pushed in 1/4" and 43 did not move. I'm guessing this may be normal and most people probably don't even look at the plunger before installing. When I got back home I tried to again install the LS7 lifters and I was able to get them all in and set 1/2 past zero. They had been soaking in oil all morning also but I don't this mattered. 15 of them were pretty tight on the 1/2 turn and that same one was easier then the rest. I'm pretty sure though everything will be fine. I don't understand the difference in plunger tension on the lifters. I thought maybe the ones I had were sitting on the shelf too long and were bad. I think I was over complicating things trying to avoid any mistakes.