Engine: Harland Sharp rocker arm users, take note...

[Mike Van Veghten]

For ALL that are or will be using Harland Sharp roller rocker arms with the OEM style cam/lifter -

Here's what I've found:
1. Studebaker uses 3/8" dia. ball on both ends of their pushrods.
Harland Sharp furnishes 5/16" cup adjusters when you buy their rockers.
BAD for oiling..! Very little bearing surface.

2. T&D Rocker Arms seems to be the only place in town (many calls all over..!) that has 3/8" cup adjusters.
They are $10.00 each. Plus they may not be long enough. I have "one" in the mail now to see if they will work properly.

3. Smith Brothers will furnish thin wall 3/8" dia pushrods (like Stude only better material) with 3/8" ball on one end and 5/16" ball on the other end.
They are $9.00 each.

Actually most pushrod builders will do this, but at $9.00 ea, I felt in not nesessary to continue my search. I'll get them out a sample pushrod hopefully tomorrow.

Mike

P.s. - T&D can also build basically one of the best, most accurate rocker arm assemblies in the industry, but to do this for the Stude engine AND make it somewhat affordable to us, they'll need to build 20 sets (sound familliar ?).
And for what it may be worth, they use roller bearings rather than bushings like most. Their shafts are designed for this.

Any thought's out there..?

[allstudedude]

Thanks for the tip Mike, I've just ordered a set from HS, that's why there has been no rebuild updates. Do the stock Stude adjusters not fit the HS rockers.

Phil.

[Mike Van Veghten]

Phil -

Unfortunatly not. First thing I looked at. The Stude adjusters are smaller in diameter. I even thought about inserts in the rocker arms..!

The best thing I've found so far (and have done), is to buy new pushrods with the 5/16" ball on one end.
The T&D adjusters are actually "more" expensive thAn new pushrods..!

I called Smith Brothers Pushrods. A new 3/8" dia thin wall (same as stock but better material) tube, 3/8" ball on one end, 5/16" ball on the other end for $9.00 ea. Don't know the delivery time yet.
I sent them a sample pushrod so they know the length to make them.

VERY important - Make SURE that the rocker roller sweeps across the valve tip correctly before ordering pushrods. Use a felt tip marker to mark the valve tip, install a rocker, pushrod, set the lash. Rotate the crankshaft one full turn. Remove everything. Notice where the witness mark on the valve tip is.
It needs to be as close to center of the valve tip as possible, for several reasons. You may have to add shims under the stands, or (like me) you may have to remove material from the stands. And in either case, the pushrod length will change.

If you don't do this verification -
1. You'll get side loading on the valve from the rocker (extra friction, premature wear of the guides, valve seats).
2. You'll loose valve lift.

Also, one thing I did that will help everything last. Another thing that Stude did.... Drill the hole in the adjuster all the way thru. There is a hole part way thru the adjuster now. Just finish the hole the same diameter as the existing hole. This will allow oil splash to go down and lube the ball & socket. It's easy to do. Only the socket is hard and it's got the starter hole in it, so the remainder is like drilling normal good steel. Use a drill/tap lube.

Hope this helps some.

Mike

P.s. - Don't try to mate the 3/8" and 5/16" ball and socket. It'll fail.

[Mike Van Veghten]

I received the adjuster from T&D Machine today. As you might expect, a very nice part.

AND, it "will" work in the H.S. rockers with stock Stude (3/8" ball) push rods.

I was a little concerned because of their length measurement and the H.S. measurement, which is one reason I just bought one..!
But holding side by side with the H.S. adjuster....perfect.

So there you are, two options for making Harland Sharp rocker arms "work properly" in the Stude engine.
And while I don't know if, like the H.S. adjusters, the T&D adjusters can be drilled thru, if anyone does buy a set, I'd recommend doing this if possibe. Oil needs to come from somewhere.

Will also let you know how the pushrods turn out.

Mike

[Xcalibur]

My experience has been that HS's adjustment tends to loosen more than others. Of course, that was under VERY hard use.

[Mike Van Veghten]

X -

That would fit with the larger ball and the smaller cup and the lack of even "sorta" proper oiling..! The wearing of the softer part into the harder part.
Thanks for your note. Just adds credence to the problem I'm trying "not" to have..!

I should have the new pushrods by Wednesday or so.
I've also finished drilling the adjusters all the way thru and deburring all of the holes. Even the side hole that Harland Sharp SHOULD HAVE USED to pressure oil the pushrod / adjuster interface...!

Mike

[Mike Van Veghten]

Update -

Got my Smith Brothers pushrods today.
The balls are as you might imagine are machined, have a nice solid shoulder to seat on the tubing. The balls even have the small flat on the end like the Stude balls do. I noticed no signs of a crooked cut on the tubes at the tube/ball interface, a nice tight joint. The balls are of the full round type. I think they call them the 270 degree ball. The tube isn't tapered, the 5/16" ball's shoulder/plug is made for the larger tube.

I had 17 made, measured them all, all are within .003" in length. They "are" .008" longer than stock..! No concern here.

I may have mentioned that I spaced the rockers to sit inline with the valves. This puts the pushrods REALLY close to the hole in the heads add to that these are 1.6 ratio rockers...so they are CLOSE. When I was doing the porting, I deburred the crap out of them...and luckilly it looks like I took enough off of the pushrod tubes to clear...NOT by much but at least one head is good. I rotated the crank to put the rockers at full lift and with everything static, all is well. Yes, I'll check them after a few miles..
One head is finally torqued...!

Note - I also deburred "all" of the holes in the adjusters, even the little side oil hole, they were sharp as razors...where they told me that they had breakage problems..!

So there you have it, two ways to properly utilize your Harland Sharp rockers, new adjusters from T&D Machine with the 3/8" cup or new pushrods with a 5/16" ball on one end.

A hand full of money I/we shouldn't have had to spend, but it's now done and ready to run.

Mike