Harland Sharp Roller Rockers -340 ??

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65 Mopar

65 Mopar

66 Ficks
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I had PRW aluminum full rollers on my 340 and last week nbr 7 intake valve adjuster broke off
Lucky I found all the pieces in the head.. but I'm not taking any more chances with these.. they've been in the engine and fine since last year but after a smoke show I heard the valve clacking..

Fast forward, I bought a Harland Sharp set up from Summit .. love the rockers but the hold down holes through the shafts are 3/8 and the ones on my heads are 5/16!

Is there any way to use these new Harland Sharps without tapping out the heads for 3/8 studs/bolts?
 
Check where the adjusters were set, they don't look threaded very much at all. Shouldnt show that many threads above the adjuster.
 
I agree. There should be at least a minimum of 2 threads showing on the ball end of the adjuster for correct geometry.

Ken
Edison, NJ
 
I broke off two adjsuters on my harlands, come too find out the torque setting on the lock nuts is only 25ft-lbs... whoops! dont over tighten them and buzz the motor up or they will break the nut off!
 
MOPAROFFICIAL said:
Check where the adjusters were set, they don't look threaded very much at all. Shouldnt show that many threads above the adjuster.
Click to expand...

I haven't even put them on yet, I am at a stand still till I find out about the hold downs. I spoke with summit and the person I talked to didn't know.. I tried calling Harland Sharp and Friday's is the only day they are only open till 11:00am
My engine machine shop is on vacation this week..
 
How much open spring pressure are your running, OP? That would have some bearing on whether you would want to go up in bolt size.

One possible solution is to use shoulder bolts. Here are some high grade ones that have 5/16" thread and 3/8" shoulder diameter that is available in 1/4" overall length increments. The only issue I have with these particular ones are that the threaded length is only 1/2" long, which is a bit too short IIRC to get full threading into the rocker stands. But there may be others out there. McMaster-Carr

Or you could cut some 3/8" OD steel tube sleeves with .031 wall thickness and custom make your own shoulders to go over the present studs. Swedge or epoxy the sleeves to the studs so that they are close to the underside of the nuts when torqued; they need to be just a hair shorter than the total top to bottom thickness of the shaft + clamp; you want them to extend through the shaft and clamp to locate them properly, but not be so long that the nut torques down on them; the nut should bear only on the clamp.

Either way you go, just pay attention to the 2nd from the left rocker stand on each side where the oil comes up pas the fastener into the rocker shaft. Make sure the clearance around the bolt or shoulder and the hole in the bottom of the shaft is maintained as this is one of the main flow restrictions in the system.
 
And BTW, the reason I would not hesitate to do the sleeves is that the shafts are located 100% in the vertical and in the sideways directions by curved machined surfaces in the clamps and rocker stands. The only direction that needs any location help is fore and aft, and 3/8" sleeve would work just as well as 3/8' bolts in that regard. It is really needed just to align the shaft when mounting; the clamping force does the real work of keeping the shafts located.

Now if you are running 400 or 500 lbs open spring pressure, then IMHO, you ought/need to go to 3/8" bolts anyway.
 
nm9stheham said:
And BTW, the reason I would not hesitate to do the sleeves is that the shafts are located 100% in the vertical and in the sideways directions by curved machined surfaces in the clamps and rocker stands. The only direction that needs any location help is fore and aft, and 3/8" sleeve would work just as well as 3/8' bolts in that regard. It is really needed just to align the shaft when mounting; the clamping force does the real work of keeping the shafts located.

Now if you are running 400 or 500 lbs open spring pressure, then IMHO, you ought/need to go to 3/8" bolts anyway.
Click to expand...
nm9stheham said:
And BTW, the reason I would not hesitate to do the sleeves is that the shafts are located 100% in the vertical and in the sideways directions by curved machined surfaces in the clamps and rocker stands. The only direction that needs any location help is fore and aft, and 3/8" sleeve would work just as well as 3/8' bolts in that regard. It is really needed just to align the shaft when mounting; the clamping force does the real work of keeping the shafts located.

Now if you are running 400 or 500 lbs open spring pressure, then IMHO, you ought/need to go to 3/8" bolts anyway.
Click to expand...

Thanks nm9! I need to get in touch with Harland and see if the offer the same rockers with a 5/16 setup or maybe they offer a kit to use these.. but I have to wait all weekend till Monday to find out That's the hard part:-(

I don't have crazy spring pressure; can't remember off hand..but they are oversized doubles running/matched for a solid cam.
 
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