Bill Erickson wrote:

I just finished the restoration on my '30 101 and have been trying to get the oil pump to deliver the proper amount of oil.  I know you can count drips if you have the proper plug but instead I chose to just monitor the level of the oil in the crankcase.  I take it for a 15-20 minute run, put it on the center stand and pull the upper oil level screw in the crankcase.  Each time I removed the screw oil came running out, and quite a bit at that.  I would adjust the screw in (clock-wise) a bit, then take another 15-20 minute run and again check the oil level.  I finally got to the point where the screw is almost touching the nut that locks it.  I may have 1/16" left for adjustment.  With the screw in this position I managed to measure 1 oz of oil that came out of the hole after the ride.  Was certainly better than the earlier runs but nonetheless it still seems to me that if it was adjusted properly maybe a little bit of oil might come out, but not much.  The other thing I noticed was that if I left the oil level screw out for a day or two, oil would occasionally drip and create a small puddle on the floor.  I assume that oil must be seeping through the pump and into the crankcase when it is just sitting.  Is this behavior normal?  Or does it indicate that maybe the pump needs some type of rebuild?  For the record, I am using 50 wt oil.

Any advice greatly appreciated.

The original screw length i measured some time ago was 890 thou ..  Just for reference .  Make sure your hand pump tap  is  sealing or turned  off .     These  pumps are near 100 years old   and do bypass   ,Usually  when sitting resting in the shed  mine will gain quite a bit.    when running i set my pump slightly high and never touch the Hand pump    I do run an oil ring on the  Rear cylinder.

I just checked my oil pump adjustment screw and the threaded portion is exactly .750".  I noticed a previous reply mentioned that his was .890".  Perhaps I have an incorrect screw?  Any other opinions?

Thanks Phillip.  I have not had the oil pump apart, but it sounds like that will be the next step to make sure the pivot pin you mention is in the proper position.

Was able to get to the oil pump today to disassemble it.  I ended up using a small punch on the pin (I will call this the center pin) that sits next to the adjustment screw to coax the cylinder out of the pump body.  Once the cylinder was out I tapped the pump body against the workbench and the hardened disk came out.  Since the center pin had been removed I am guessing that the disk can rotate enough to dislodge from the pivot pin and fall out of the pump.  Pivot pin is still in the pump body now.  If that is unlikely, maybe the pivot pin was never in the slot on the edge of the disk.  Other than that I don't see anything "wrong".  I cleaned everything up and am ready to assemble again.  One thing I am unsure of is the installation of the center pin - I assume it is driven in until it stops?  Or maybe when you tighten the screw cap down it will push the cylinder against the pin and it will end up in the right place once the screw is tightened?  Also I assume I am going to have to drive the pivot pin out to install the disk, unless there is a crafty way to install the disk with the pivot pin already installed.  See attached pic for a look at the parts that were removed.

Ouch. Center pin is press fit in body, and extremely difficult to get a tight fit correctly, as it locates at one end only. you may have to make a new one slightly oversized and maybe knurl the end. Take care to ensure that it is replaced straight and solid, and if you do need to make a slightly oversized end, be gentle, better to have to do it several times with different fits than cracking the body going too big first up. 
.does anyone have any experience refitting this pin with a loctite product, like loose tolerance bearing fit, that has worked successfully over a decent mileage?

For future reference, it is A LOT easier to remove and replace the pivot pin, which has a location at both ends, and can be carefully peened over at both ends like a rivet.

let us know how you go,

Tim R