Hi guys, we have had a recurring issue on a few cylinder with rocker jam nut backing off. Harland Sharp rockers on EZ heads, solid roller valvetrain. We are trying to investigate and solve the issue. My plan is the check the lifters and pushrod wear and clearance. My dad thought he solved the issue before he passed away 2yrs back and we are just now getting the engine back in the car for initial startup only to run across this issue again. I would love to hear any feedback you guys might have to help solve the issue. We just want to get it fixed right so we don't have to keep worrying about it everytime we run the car. Thanks

Do you have an LSM tool when you do the valve lash? If not, you should get one. If they still loosen up, the rockers are worn out.

I think you have a couple of soft adjusters...
seen it a few times

Make sure the flat machined into the rocker for the nut to seat against is square to the adjuster, and that the bottom of the nut is also square to the adjuster/parallel to the rocker recess/pad.

we had a hardware coming loose problem a few years back. turned out to be harmonics as our balancer/damper was going south. we changed it & after that our problem was gone. are you using the same damper as before as you might want to look at this. i know its hard to believe something like this can happen but i've just changed the replacement damper as we were seeing things fail again.

That is a very nice tool, makes it easy to torque the nuts down while holding the adjustment.

This ^^^^

20 ft. lbs. if you are not using the LSM tool that is highly recommended here. Set the lash, cinch them down and when you are done go over them all with the torque tool. The damper is interesting, another tidbit to keep in the ole memory bank. HS can send you a new set of adjusters.

This is something I've seen also. Crane gold. Replaced adjusters, and used ARP 12pt nuts as jam nuts- instead of the short nut that comes with them. Never an issue after that.

I changed to a full nut instead of the short jamb nut cause i was having a hard time tightening down because of the way the nut fits in the pocket, with taller nut I was able to tighten the nut better and never had one come loose after that.

Problem with that approach is it adds weight right where do not want it by using full sized jam nuts.

Does Smith Bros have an adjuster screw that is the proper thread size for HS rockers? A set of better screws & 12-point flanged nuts could be the fix.

I've seen some pretty crude adjuster screws that HS supplied with their new rockers a few years back that shouldn't have made it past whatever QC checks they have. Burred-up threads... adjuster ball ends that looked like the were "finished" with a hand file... real POS hardware from a company that has such die-hard supporters.

I don't know if they still do, but they used to.

I believe Manton does as well.

Dang China Rockers.

That's an attempt at humor, right?

And a good one at that.... it is comical to watch this group work diligently to remedy an issue whenever an expensive part is involved in the issue; But if the price of said part is favorable to the buyer, or god forbid if it's manufactured in China: "it's just plain a crappy part, get rid of it, I would never own it, and you're an idiot for buying it."

A couple of well-known expressions come to mind when I read your comment above:
1. Don't throw good money after bad.
2. You get what you pay for.

There's a big difference IMO between an affordable fix to a reasonable quality product (regardless of origin) to keep it serviceable vs. spending additional money on a poorly engineered product (perhaps a cheap offshore "clone" of a popular brand-name item) to try and band-aid sloppy manufacturing processes and/or (lack of) quality control issues. So, it doesn't surprise me that people are more helpful in trying to resolve issues being experienced with parts otherwise known for good quality. After all, we probably have a good idea how much it cost to get those parts in the first place.

On the other hand, spending brain power to help make a poorly-made part serviceable is going to have a limited return on time investment. At what point does the cost to correct the issue raise the price of the "budget" part close enough to what the better quality part sells for that it's no longer cost-effective to mess w/ the cheap part? If it's got one problem to deal with because of the way it's been made cheaply, is another one going to pop up after that, too? How quickly does it take for a "good deal" to turn into a monetary sinkhole?

Sometimes a "good deal" on a part is really that: a good deal on a decent part. Other times, it's pretty obvious once you have the part in hand WHY you were able to buy it at such a "great" price. Anyone who is a total price shopper -- and looks for "deals" instead of reasonable prices on good parts -- is going to get burned on occasion due to the way the parts industry has been flooded with offshore products that range in quality from "It should come with it's own garbage can!" to "It's a good bang for the buck!".

And, to be blunt, some people only learn these things the hard way. I tell my kids without hesitation that I've never learned anything the easy way. I can say with complete honesty: "Been there, done that, paid the price."

Its just a bit amusing although unfortunate for the op to have an issue with a set of rockers he probably paid a grand or better for. Cause good god that dont happen with 1k rockers but we read about every brand having issues and wearing out, needing rebuilt, ect.

Ive posted before that alot of the china products are decent to use if one does there own QC straight from the box.

These in the pics are only off because im working on the short block, and although id not use them on a heavy roller cam I do use them on a high lift solid, nearly .700 and over #500 open, K motion K800 springs. Running 6.0s in my street racer this past spring at the track.

I actually do have a new set of HS in there shrink wrapped deal and they have been there for nearly five years because ive never had a reason to use them.

To me brain power means knowing the china man has no QC so I must do my own and normally find 2-3 rocker bodies in a new set I send back to swap out. It also means knowing the limits of the china mans parts, but if one has the time to do the QC process as we all should weather its a $100 or $1000 part or an indy head, mopar head, edelbrock head or chinaman head.

As I mentioned we see rocker issues across the board no matter what brand, head issues no matter what brand, like the recently posted leaking indy new castings, ect.

I think attention to detail, matched parts and more attention to detail in parts, machine work and assembly.

I put 65 hard 1/8 mile runs on these this summer which is actually more then many here put on there track car in a year. No issues, normal wear. But yes, I probably have 5-6 hours inspecting, test running on a bench motor so time vs money spent?

Just opinions.