I just got done putting together an engine with a cc306 cam and ported stock heads. The guy that did my heads set up my valve springs for the cam so I don't know exactly which springs I have. I am using TPIS lifters and have been having problems with my rocker arms coming loose. I just readjusted them and notice that most of my lifters could be pushed in by hand. I could turn my poly locks by hand and the pushrod will push down into the lifter. I'm assuming these are collapsed, and was wondering if the lifters could not handle the spring pressure. I am fairly positive that I did not over-tighten any of the rockers.
Thanks,
Jeff

 

If you can turn the poly locks by hand, you are not setting them right.

The poly lock puts pressure in two different directions so it locks in place, no matter where your rocker is. I usually set the allen head as tight as I can and then turn the whole nut/lock as far as I can with a 3/8 ratchet. Figure out where to start your lock if you get them too tight this way.

And yes too much spring can kill your lifters, but so could too little. You need to find out what springs you have and if they are close to what you actually need. If a lifter is not pumped up you should be able to push them by hand. (stock style anyways)

 

Try adjusting them when it is running and see if that helps. Some of them bleed down when the engine sits, but that's no big deal as long as they work when it's running. Tighten them like the other guy says to, thats the only correct way to not have them come loose. And if you have stock studs with the cupped tops, it's doubly important. Better yet, take the studs out and face the ends so they are flat.

 

I know how to use poly locks and I did tighten them the way you said. What I'm talking about is that I back off the allen screw all the way, I find zero lash, and then I can continue tightening the locks passed zero lash, by hand, compressing the plunger of the lifter. I've never had this happen before, and not all the lifters do this, so I was wondering if these lifters are collapsed.

I guess the main question I have is: if I have the proper springs for my cam, which is a fairly high lift cam, will they be enough to collapse stock or stockish lifters? I believe the TPIS lifters are modded stock lifters. I'm wondering if I will have to buy morels or something similar.

Thanks for the help

 

That's normal, some of the lifters have bled down. Those are the tricky ones to get adjusted correctly.

 

Should I still set them at zero lash with normal preload or go farther? Setting them up normally they seemed as though the rockers would bounce off the ends of the pushrods.

 

like stated before try to adjust them with the car running, that way you can be sure they are not bleeding down and go from there

 

I ran into the same thing years ago. It is really hard to tell where zero is with these. You should be able to set them the way you described and once it runs and pumps the lifters up it will be fine.

 

Setting the preload on a lifter that has been bled down should be done the exact same way as a lifter that has not yet bled. But here is a tip...

With ploy locks and studs that are in good condition finding zero lash should not be an issue, just turn the poly by hand untill the slightest resistance is found then back it off and turn down again. Do this untill you get a feel for zero lash with out putting pressure on the plunger spring. Once found you can make your preload adjustment weather it be 1/16,1/8,1/4 or 1/2 a turn past zero lash and you can do this by hand since there will be very little resistence. Tighten the lock and hold the nut, once set you should be able to push on the back of the rocker and have some movement which may seem like a lot, this is normal and that clearence will be taken up by the hydraulic pressure behind the plunger once the engine is started. It may clatter for a moment until oil pressure builds but will go away. If you overtighten the preload or miss the zero lash point it may hang a valve open. Personally I prefer to set lash on a bled out lifter, it makes you take your time and avoids the possibility of setting preload on a lifter that my be fully pumped up.

 

Ok thanks guys. That is how I set them up, I was just unsure if this was normal or not.