Torque # For Iron Rocker Lock Nuts?

[midnight340]

just did a road trip plus 1/8 mile fun drags. Had one adjuster shear off under the lock nut. Fortunately the nut/top of adjuster was sitting in the head!

Machine shop had told me I needed 30 ft/lbs on the ARP lock nuts. I didn’t go that high, but what would recommend??

And who makes the best adjusters??

 

[RustyRatRod]

For an ARP 3/8 adjuster, 30 is probably about right. I would think ARP or Crane would be good. Manton is also another.

If these are the stock 273 iron rockers, you should make sure the area under the lock nut has been machined or dressed with a file until it is completely flat. If it is left as cast, the lock nuts will work loose........and break the adjusters.

 

[brian6pac]

Are they 273 rockers ? if so are they machined flat were the nut sits or a rough casting?

 

[midnight340]

Machines flat. Not sure what the adjusters are, pretty sure they are new ones from when I had the 273 rockers bushed. Will replace them all for sure witH ARP OR similar.

 

[Lefty71]

Whos adjuster bolts are those??

LSM Racing Valve Lash Torque Wrenches TQ-100-3

 

[RustyRatRod]

View attachment 1715370714 Machines flat. Not sure what the adjusters are, pretty sure they are new ones from when I had the 273 rockers bushed. Will replace them all for sure witH ARP OR similar.

Dammit. Snapparoony! Almost looks cut!

 

[MOPAROFFICIAL]

I've never had one come loose or sheer before.
I tighten them as such... with a lil smack of my palm on the wrench...maybe 2.
With some things...the 'feel' from 'experience' is all you need and imo this is one of those things.

Ive used and reused ,with success, harland sharp adjusters...but none others. Maybe arp makes them... maybe not. never looked into it. Hope you figure it out okay.

 

[midnight340]

I believe these were new adjusters that were installed by Rocker Arms Unlimited when I had the rockers bushed and clearanced. I emailed them to ask what they are, but haven't heard back yet.

this next photo I tried to delete, but can't figure out how. Oh, well.
(This is the exhaust rocker at full lift.)

 

[70aarcuda]

Whos adjuster bolts are those??

LSM Racing Valve Lash Torque Wrenches TQ-100-3

Best tool I ever bought....been using one for several years now....also use it to torque rocker shaft hold down bolts..

 

[midnight340]

Gary at RAU just wrote to tell me that these are Smith Bros. adjustment screws and that they have never had one shear before!!!

Very apologetic and he's sending several extra screws. Nothing but great service from them, so no blame. I guess S*** happens, even with the best parts!

(He said he'd bring the torque down to 25# and should have no more problems.)

 

[toolmanmike]

Gary at RAU just wrote to tell me that these are Smith Bros. adjustment screws and that they have never had one shear before!!!

Very apologetic and he's sending several extra screws. Nothing but great service from them, so no blame. I guess S*** happens, even with the best parts!

(He said he'd bring the torque down to 25# and should have no more problems.)

Inch pounds or foot pounds?

 

[midnight340]

Ft/lbs. it seemed a lot to me, but my machine shop that builds a lot of performance mopars says they usually are closer to 30-35 ft/lbs.

I used 340 in/lbs (28 ft/lbs) because it’s easy to remember. Still sheared off.

Automotive Machine and Performance that I go to, says they epoxy rare earth magnets in the head corners and openings. Picked up some from Harbor Freight today. Peace of mind.

 

[Wyrmrider]

usually break is because rocker surface is not flat and parallel with nut face so nut is only sitting on one side
I'm sure Rocker Arm Rebuilders uses a jig so their spot face should be "square"
BTW hard to do the "square" with a file

 

[midnight340]

usually break is because rocker surface is not flat and parallel with nut face so nut is only sitting on one side
I'm sure Rocker Arm Rebuilders uses a jig so their spot face should be "square"
BTW hard to do the "square" with a file

I guess if I thread a long bolt into the rocker and lay a straight edge across the surface I could check it with a machinists square.

 

[MOPAROFFICIAL]

View attachment 1715371002


I believe these were new adjusters that were installed by Rocker Arms Unlimited when I had the rockers bushed and clearanced. I emailed them to ask what they are, but haven't heard back yet.

this next photo I tried to delete, but can't figure out how. Oh, well.
(This is the exhaust rocker at full lift.)

View attachment 1715371001

I like to see a couple threads above the nut and below the rocker. It doesn't look like that there...

push rods about .040-.050 too long?