[joey308]

ok i have a 91 mustang with trickflow stud mount heads that i just installed. i set the valve lash and got everything right and i rotated the motor over a few times and all of the rocker arms i can move side to side there not tight but when i set them they were tight and i couldnt move them. please help because i dont want to start this thing up and blow it up. and when i set them i primed the motor so the lifters were pumped up. thanks joey

[lxarlo]

you couldnt turn the motor over after you set valve lash? had you already primed the engine at this point? that may be why.

[mmb617]

How exactly did you lash the valves? Did you use the exhaust open / intake close method? When the valves are properly set you can move the rockers a little on cylinders that the valves are not partly open.

Let me give you a little heads up, when you tighten the poly locks, you need to be sure they are really tight. I had a few rockers back off on my new motor. The second time I tightened them till I heard them "squeek", and they haven't moved since.

[EagleAutosports]

Originally Posted by mmb617

How exactly did you lash the valves? Did you use the exhaust open / intake close method? When the valves are properly set you can move the rockers a little on cylinders that the valves are not partly open.

Let me give you a little heads up, when you tighten the poly locks, you need to be sure they are really tight. I had a few rockers back off on my new motor. The second time I tightened them till I heard them "squeek", and they haven't moved since.

I agree. The rockers need to be able to wiggle a little bit because having them too tight is just as bad. As long as the roller tip isn't coming off the valve tip, and the rocker body is all that's wiggling, they should be ok. Don't forget that lifters can still bleed down even after being primed.