Lifter Preload and Noise question

[rwkhaussupply]

I have read more than I care to over the last 12 hours about lifter preload and pushrod lengths etc...

I dont know any of the exact specifics now on head milled, or decking etc. I have a new clearwater head with their recommended springs for the Mopar mid level cam I just installed. Engine fired up for the first time last night. I started it and pulled it up to 2100rpm and set a feeler gauge under the throttle stop screw to have it hold at 2100rpm. Got out and was just observing everything, since it basically is new everything but a basic short block. Everything looked good, it cooled exactly how I figured it should 190 up to 210 dn to 190, etc.

The valve noise seemed excessive. I dont know if it was just the higher RPM and hood off and just being right there, or if the preload is playing a factor.

The pushrods I think I last installed were 9.650. I had read that in the middle of the lifter was good. SO I got just about 3 turns of preload out of a lifter and with these pushrods I got 1.25-1.5 turns. I am using HS non adjustable 1.7 RR's. I did not check valve tip to roller area, as I didnt even think it was needed to be checked. But after reading I guess I could/should have.

But wouldnt having a bit to much preload eliminate noise, not cause more noise?

I am prepared now (it only has 7min of the break in so far) to pull the PITA valve cover off (its in a TJ and the area is Tight with the wire harnesses) and check the tip to valve area with a revolution of the cam. And if ok install a ford spacer, or a shorter pushrod.

My main concern though, is would a bit too much preload cause noise? And I am reading that about 1/2 to 3/4 turn of the rocker retainer is about where I want it, optimally?

[Cheromaniac]

And I am reading that about 1/2 to 3/4 turn of the rocker retainer is about where I want it, optimally?

One full turn of the rocker arm bolt from the "zero lash" point is equal to 0.060" of lifter preload, so ideally you'd indeed want the rocker arm bolts to reach the correct torque about 1/2-3/4 of a turn past zero lash.

[rwkhaussupply]

That part I have read and found now. BUt would you think having too much preload (about .090) would cause excessive valve train noise?

[BADASYJ]

I dont see how a little too much preload could effect noise. Now if the valves don't close completely because of to long of pushrods it will make a racket.

[rwkhaussupply]

I dont see how a little too much preload could effect noise. Now if the valves don't close completely because of to long of pushrods it will make a racket.

I think I found it, but wont know till I get a few to pull the valve cover. The springs that clearwater uses are 1.460od and I have read a few that say the comp extreme springs are 1.47 and they rub on the alum valve covers. SO I am assuming I have springs rubbing on the valve cover. Will pull examine and then swap to a stamped steel OE to fix if so.

[BADASYJ]

Ahh hell it'll stop after a few more hours of running. It'll make its own groove in the aluminum, those are self clearencing valve springs. Lol

[rwkhaussupply]

Ok so...

A spring and retainer with a 1.460od will rub on the alum valve cover by only about .020 I think. But they will rub. This was With a 5/8 spacer that likely isnt even needed, as I have the HS 1.7 roller rockers. But was trying to be safe. With that spacer though, the OE valve cover went right on and now quiet.