Crane Rocker Arm Issue

[inviolet]

Hey Guys,

I've had some rocker arm issues of late. A have a set of Crane 1.5 rocker arms that I had bought used, After 10,000 miles or so, the pins that hold the ball bearing above the valve steam started walking out (Excessive valve float or Junk product?).

Its happened twice now(to different cylinders/sides), and so far I've been lucky twice catching the issue before it became a bigger issue.  Last time, as a precaution,  I took off all the Rockers and one by one I mushroomed all the ends of the pins so that they can't walkout no more. So far so good but needless to say twice bitten twice shy. Its a 496, the Cam is a hydraulic roller with roughly 550 lift. I'm thinking about buying a set of these Harland Sharp rockers that Mancini Racing sells. They look like they require the least amount of modification to go with my setup. Any suggestions?

http://chucker54.stores.yahoo.net/b15alrowibih.html

[cudabob496]

hmm, I have a solid roller in my 496, .625 lift, and crane gold rockers have been
perfect for 14 years.

wonder if you're getting good oil flow, or maybe the used ones you bought were abused.

[Chryco Psycho]

Personally I would look at a stainless rocker like PRW or Comp , or a nodular iron rocker Like the Crane , Alum is OK for racing , not so good for long term street use .

[cudabob496]

might get Crane's opinion

as far as valve float, what springs are you using, and how high do you rev it?

[72bluNblu]

I had a similar issue with a set of Harland Sharp's, the roller pins were hogging out the holes they were sitting in at the tip of the rocker. One was bad enough that it allowed enough room for the lash cap to part ways with the top of the valve. Mine was due to using incorrect (too light) valve springs. Fixed that, but unfortunately the Harland's were totaled. I'd look for a spring pressure or geometry problem. 

[cudabob496]

ya, this is a simplistic answer, but maybe some kinda valve train geometry issue,
like pushrods too long.

[1 Wild R/T]

Simply the best trouble free rocker arms for a cam with less than .600 lift & spring pressures less than 550 lbs....
Ductile iron body, Hardened steel wear pad at valve contact, hardened steel adjuster & this set has been to RAS to be receive bronze bushings & have the geometry corrected... No rollers to fail, no stainless steel to gall & seize... Just parts repeatedly proven to go 100K miles without trouble...

[cudabob496]

Simply the best trouble free rocker arms for a cam with less than .600 lift & spring pressures less than 550 lbs....
Ductile iron body, Hardened steel wear pad at valve contact, hardened steel adjuster & this set has been to RAS to be receive bronze bushings & have the geometry corrected... No rollers to fail, no stainless steel to gall & seize... Just parts repeatedly proven to go 100K miles without trouble...

What's RAS, and what geometry is being corrected?

[1 Wild R/T]

What's RAS, and what geometry is being corrected?

RAS is Rocker Arm Specialists   And virtually every rocker arm you buy is gonna have variance ratio wise, when they bore the rocker to install the bushing they take that opportunity to correct the variance....

Isky hasn't produced them in 20+ years but NOS sets are still floating around, FWIW these things are bullet proof, same design as original equipment  on Max Wedges & the Long Ram/Short Ram cars plus many successful S/S still seek them out today because they take the abuse without failure...

[inviolet]

Simply the best trouble free rocker arms for a cam with less than .600 lift & spring pressures less than 550 lbs....
Ductile iron body, Hardened steel wear pad at valve contact, hardened steel adjuster & this set has been to RAS to be receive bronze bushings & have the geometry corrected... No rollers to fail, no stainless steel to gall & seize... Just parts repeatedly proven to go 100K miles without trouble...

Are there oiling holes on both sides? I can't see from the picture.

I had bought a set of Harland Sharp's with the needle bearings, looked heavy duty, but they only had oiling holes on the push rod side, they say because the needle bearings drops oil pressures too low for additional holes. They told me to run oil restrictors and they would drill me the holes, but I'm not to crazy about that idea for street car.

How can I checked for geometry issue? But I doubt it's a geometry issue, after 10,000 miles or more I have had no other issues. FYI, The Crane's on there now look clean, no strange marks.

Here a close up picture of the Harland sharps with needle bearings. (no oiling holes for valve steam side)

[cudabob496]

Are there oiling holes on both sides? I can't see from the picture.

I had bought a set of Harland Sharp's with the needle bearings, looked heavy duty, but they only had oiling holes on the push rod side, they say because the needle bearings drops oil pressures too low for additional holes. They told me to run oil restrictors and they would drill me the holes, but I'm not to crazy about that idea for street car.

How can I checked for geometry issue? But I doubt it's a geometry issue, after 10,000 miles or more I have had no other issues. FYI, The Crane's on there now look clean, no strange marks.

Here a close up picture of the Harland sharps with needle bearings. (no oiling holes for valve steam side)

Looks like a defect in the roller surface?

[inviolet]

One of the new rocker bearings had a small notch in it. I don't think it would have been a big issue. However I did end up returning them because they didn't have the oiling holes on the valve side. 

[cudabob496]

One of the new rocker bearings had a small notch in it. I don't think it would have been a big issue. However I did end up returning them because they didn't have the oiling holes on the valve side.

not good quality control from HS

[1 Wild R/T]

The Isky's oil both sides...

[inviolet]

Does anyone run these Mancini Racing / Harland Sharp Rockers? Any experience with these rockers?

http://chucker54.stores.yahoo.net/b15alrowibih.html