I want to install a restrictor in the rocker shaft pedestal to cut down the amount of oil flowing to the rocker shaft.I deepened the oil groove in the cam when I rebuilt the motor last year.Now I have too much oil and its flooding the head because the oil can't drain fast enough.What size drill bit should I use to drill the restrictor plug?This is a stock motor. 

  

An oil restrictor size of 0.078” (5/64” drill) should accomplish what you want.  Any bigger than this will end up being an excess of oil.

 

Here’s the link to a recent thread discussing the oil supply to the top end and restrictor sizes.

http://www.y-blocksforever.com/forums/Topic10041-3-2.aspx

Lorena, Texas (South of Waco)

Thanks Ted! What does a set screw look like?I was going to use a small pipe plug with the Allen key head like the oil gallery plugs do.What is the size designation needed for a plug/set screw  thread/size?

  

I use a 1/16" (.062") drill and still get plenty of oil to the top.

   God Bless.   Tim                           http://yblockguy.com/

350ci Y-Block FED "Elwood", 301ci Y-Block Unibody LSR "Jake", 312ci Y-Block '58 F-100, 338ci Y-Block powered Model A Tudor

tim@yblockguy.com  Visalia, California    Just west of the Sequoias

Mark:

The setscrew looks like the plugs you refer to, but come in much smaller sizes.  The oil feed hole can be tapped with a 5/16 tap, and a drilled 5/16 set screw installed.  Only tap partway through the stand, so the screw can "bottom out" and stay put.  Set screws come with straight slots or allen hexes.  Local hardware stores should have them.

John - "The Hoosier Hurricane"

Mark:

Just to add to John's advice.



You will have to grind the allen set screw shorter as it will be too long and either hit the rocker shaft or be exposed at the bottom of the rocker stand. The allen screw has a tapered end with a circular area to lock pulleys etc solid to shafts. You need to grind this area flat first. Do not take anymore off the bottom than is necessary or you could get through to the hex and loose the orifice you have drilled. The top will need to ground also, just leave enough for your allen key to fit to snug the set screw and slightly below the rocker stand. Trial and trim to do it.

marv

Thanks guys! Great advice.

  

Mark:

You can find setscrews as short a 1/4" which will not have to be shortened.

John - "The Hoosier Hurricane"

they are hard and dont drill easy.

I took a somewhat different approch,  I pressed a plug in the inverted U tubes with a 1/16" hole in it. That way you get oil flowing down the front and back of engine to lube the timing chain and dist gear and pressure in the rocker shaft itself. I also have early Dove Rockers which did not have an oil groove in them until I added it. I felt that the added oil was necessary through the rockers to the roller tips and the pushrod ball.  I have PC teflon seals on the valve stems which are supposed to be better oil control so more oil in the area is not a problem.  I have not had any wear problems in the valve train and the last time I had it apart the were no signs of wear on the rockers with something like 10,000 miles on the engine.

Doug T

The Highlands, Louisville, Ky.