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Here is the pump out of the engine I have. Packardv8 has confirmed in my build thread that the pump is a 1st Generation pump that has a "hash pipe" attached to the pressure relief valve, which is a dealer fix.

https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?post_id=23692#forumpost23692

However, the wear on the end of the shaft that goes into the distributor troubles me. What do you think? It pumps like crazy when I attached a cordless drill and put the pick up screen in a pan of oil. It shot oil across the room!

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Hash pipe?!? Rather than draw the attention of the authorities with such talk, let's just call it a 'sump tube'.

That tube was promoted by the factory (see STB 56T-20) for field service of the early design pump WRT to lifter noise caused by low oil pressure. For some reason (and perhaps more than just warranty cost), they didn't want dealers replacing those with the late design pump that had been introduced in engine production.

The second design pump has the pressure relief bore threaded and plugged (with some other internal differences); the body casting number is 6492430. So, you definitely have the early design pump.

Dunno what to make of that spot on the shaft. Doesn't look like simple wear. That end of the shaft just slips into a socket in the bottom of the distributor drive gear. Did you inspect the mating part for any corresponding marks?

Meanwhile, with no load on the outlet side, I'd expect any pump that's capable of turning at speed to shoot a stream of oil.

Were you having a problem with the pump, lifter noise, or low pressure prior to its removal?

Whichever way you go, definitely do not re-install that intermediate drive shaft. It's the worst worn I've ever seen.

Check the distributor also. When the intermediate shaft is so trashed, there is usually some corresponding wear on the mating surface.

There had to be some serious resistance somewhere to cause that damage. When you disassemble the pump, shoot some photos of the inside of the body, the gears and the vacuum pump driveshaft.

Since the pump is out and the engine is apart, if you want to retain the vacuum pump, I'd recommend my rebuilt Packard pump with the longer pump body bearing.

If you choose not to retain the vacuum pump, go with the Oldsmobile conversion kit.

jack vines

Also, I'd remove the distributor to see if it has some serious resistance to rotating freely.

That is unusualy heavy wear. How many miles on it???? Most likely the vacuum pump was binding. Look at the hex key that drives the vac pump. Probably broken at the center.

Pay close attention to the screws that hold the die cast vac pump housing to the pump to see if any of them are loose.

Also, I'd remove the distributor to see if it has some serious resistance to rotating freely.

Just thinking about it, that was a stupid suggestion on my part. Sorry about that.

remissa sunt tibi

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Yet, if there's corresponding wear on the distributor drive gear, is it possible that worn distributor housing bushings and resulting misalignment of the mainshaft caused this wear?

Bob Aller told me how to build a oil pump pressure tester out of aluminum plate. You cut a piece to fit over the output of the pump. You drill and tap for a gauge in the output , and put the pump on a drill.

You can test with oil above and below the area where the shaft enters the casting. The area where the air enters the pump if not bushed.