Thanks John.If the problem persists with the new shaft assemblies I will have to install a restrictor as others have done.

  

Mark:

Too much oil is what you found.  The drains can't keep up, so the oil level rises until the oil drains through the pushrod holes.  At that point the valve guides are flooded and oil can run down the guides and be burned, not to mention the gaskets being submerged in oil and more prone to leakage.  Plugging the drain tubes to "pressurize" the rocker shafts as many do only makes the problem worse.  I can run my engine with the covers off, there is a gentle stream coming from the overflow tubes which exit into a pushrod hole.  I have 60 psi oil pressure at hot idle.

John - "The Hoosier Hurricane"

Frank, only about 1/16" wide and .030" deep, i figure it has oil pressure at feed holes so joining them together by adding groove completes circuit, so to speak.

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

Bill,

    How big? Wide, deep etc.

Frank/Rebop

Bristol, In ( by Elkhart) 

I regularly  machine a groove in the x drilled cams and it works for me.

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

if its to much you can always put plugs in the bottom of the rocker stands.thats what i did with my last engine.i got a cam from neilsen cams that was both cross drilled and grooved.anybody else ever get one of those.

How much oil to the rockers is too much oil?When I rebuilt my 292 last year I had the cam oil groove deepened as I was advised the original cut was too shallow at .019(I think thats what it was).Now I have LOTS of oil to the topend ,so much so I cant  run the motor with the covers off.The oil wont drain fast enough to stop from overflowing the head.Now that was with the old worn shafts and arms which I reused for the time being.I just purchased 2 Ford remanufactured rocker assemblies(with the newer self locking adjusters) which I have not yet installed(waiting for warmer weather).Should I be able to run the motor at idle with the covers off?Hoping that the old assemblies were simply worn to the point that the oil was passing at higher volume than it will with the new assemblies.

  

Ted: It's just as likely that because Ford knew the Y-block was to be phased out, they cleared out there remaining old stock of cross drilled cams.

Paul

Cross-drilled camshafts in the late production Y pickup engines are common. While the cross-drilled camshaft oil design permits an intermittent and back and forth oiling to the top end, the grooved camshaft permits a continuous flow of oil to the rockers.  The grooved camshaft oiling design has a propensity for shutting off the oil supply to the top end with any appreciable center cam bearing wear which may be why the last of the Y's went back to the cross-drilled oiling supply for the top end.  As John mentions, putting a groove in the block behind the cam bearing permits a much larger supply of oil to the top-end and so much so that a restrictor at the rocker arms may be required.

Lorena, Texas (South of Waco)

When I grooved my block behind the bearing, I found I had too much oil to the rockers, had to put restrictors in the feed holes in the rocker stands.  I used .032 restrictors.

John - "The Hoosier Hurricane"