Rockers won't adjust

[Southtowns27]

I got a free set of 1.6 rockers for my 283. They were all brand new in the boxes. I put them on, adjusted them to zero lash, and started the engine. LOTS of clacking. I figured maybe they were just a little loose so I started snugging them down a little at a time. It got much better, but they're still clacking away. If I tighten them any more than they are now, I can hear the sound of the engine change since the valves aren't closing all the way. Anyone have any ideas?? :? I've never had a problem adjusting valves before

 

[dq409]

Sounds like you need longer push rods with the higher lift of the 1.6 rockers,,,, dq

 

[Southtowns27]

Hrmmmm...You may be right with that. I wish I rod a pushrod length checker. Maybe I'll pick one up. But I don't really see how longer rods would help a whole lot....They're currently ticking, but if I tighten them more, the valves don't close all the way. It's not like I'm out of stud or anything. Maybe I'm missing something here. If I am, please explain. Thanks!

 

[dq409]

Sorry,,, brain fart !!

Coffee had not kicked in yet !!

hmmmmmmm,,,,,dq

 

[gtendow]

are they hydraulic lifters?

 

[Bungy]

Maybe your pushrods are hitting the heads? The 1.6 will move the pushrod closer to the stud. Don't think that would make a clacking sound though. Check for wear on the pushrods at the head opening. Do you have enough clearance between the rocker stud and slot in the rockers at full lift? Are the rockers the late model type with the guides at the valve tip end?

 

[Southtowns27]

Yes they are hydraulic lifters. The pushrods aren't hitting the head. The slot on these rockers is huge, plenty of room for the cam I'm running. No, these aren't self aligning rockers. I don't see how much difference it could make since my 1.5's weren't self aligning either. I actually put them back on, now it's nice and quiet again. It doesn't happen often, but I'm completely lost on this one. It doesn't make sense that one is nice and quiet and adjusts easily and the other sounds like a machine gun...

 

[Bungy]

It would only matter if one set was self aligning and the other wasn't. Were you using the same rocker balls and nuts as the 1.5 set? The 1.6 set are stamped steel just like stock correct?
I'm very confused also (of course that doesn't take much)

 

[Southtowns27]

The 1.6 rockers came with their own pivot balls and new nuts. They're stamped steel just like the 1.5's.

 

[dq409]

South, I would post this over on ChevyTalk in the performance forum and see what kind of answers you can get. ,,,, dq

 

[Southtowns27]

Thanks for the idea

 

[60convert]

I would start by swapping back to the 1.5s to see if that gets rid of the noise at least then you know your cam lifters and push rods are the same. Then after that if its quite i would swap 1 set of the 1.6s on at a time and see where the culprit is otherwise mayber there is interferance with the push rods and the 1.6 rockers??? maybe a different length???
Jesse