Oil Pump Rebuild Question - 28-30 Plymouth

[johnRFain29U]

Dennis,
     I decided you were probably right and reassembled my oil pump with the bevelled part of the vanes on the trailing edge.  After some work with a drimmel tool, 600 grit sand paper, and much measureing and experimentation with different gasket thicknesses, I got it working.  It holds over 40lb or pressure at operating speed (40-45 mph), and at idle has about 25 lbs.  This is better than it was before the rebuild.
     Then and Now put in a new bushing and installed new vanes and springs.  They also smoothed the cover (a grove had worn there).
      I had a local shop smooth out the bottom - the large part of the shaft had worn a grove.  They also cut the top down an equal amount, so the depth would be proper.
     I used a drimmel tool to smooth out a vertical ridge that the vanes were also catching on, then smoothed it out with 600 grit sandpaper.
     The cover gasket provided by Then and Now was .012 inch thick. Thanks, John 29U 4 Door

[DENNISKS]

John

I am on my way to Waumsetter, WY. I should be back in Indiana by Saturday if the winds do not get to bad out here.  I will try to get a look then.

Dennis

[12905]

I think the bevel must be on the trailing edge. If it is placed as the leading edge, then the oil pressure will force the vanes inward and by-pass them. Note that I don't know this for sure. I am basing my opinion on what I know of the behaviour of fluids under pressure.

[johnRFain29U]

Dennis,
I think the beveled edge is on the trailing edge, although it seems counter-intuitive.? If you get a change to pull that cover and look, I would appreciate it.? (The pump turns counter-clockwise, looking at it with the cover off.)
John

[DENNISKS]

John

I have a spare pump over in storage. If you do not get an answer in a few days when I get back home I can take my spare one apart for you. Right now I do not have an answer that I am 100 % sure of.

Dennis

[johnRFain29U]

I am rebuilding the oil-vac pump on my 29U Plymouth.? The 2 oil pump vanes are beveled on the end.? Does the beveled side face the direction of rotation, or should it be the trailing edge?