Re: V8 oil Pump ID?

Posted by Craig Hendrickson On 2012/3/4 14:25:28

Rather than start a new thread about the "fatal flaw" in the Packard V-8 oil pump relief valve design, I'll go with the current thread drift made by Brian and Jack.

Here's a picture of the cross section of the oil pump through the relief valve, spring and sump tube as shown in STAB-56T-20:



Here's a pic of the relief slide valve, spring and gland plug (no sump tube) out of one of my used Packard V-8 oil pumps.



NOTE the discolored area on the side of the slide valve and the recessed surface in the middle. The discolored areas are what causes the sticking in an open position. This is also the part that was supposed to be cleaned off with crocus cloth to "fix" the problem. IMO, the recessed middle exacerbates the sticking problem because the edges tend to snag on parts of the relief hole.

Here's a comparison between the Packard V-8 relief valve assembly and one from a new Olds HV oil pump.



NOTE that the Olds is much larger and has NO recess in the middle. Both are improvements over the Packard design.

Craig