Re: High Mileage Packard V8s

Posted by BH On 2007/6/4 19:10:26

Well, I'm just thinking that if the lifter noise is connected to premature wear of the pump, then the vac pump isn't at the root of that problem - else there would have been no need to advise Studebaker dealers of the sump tube kit (effectiveness of that kit not withstanding).

Wouldn't the pump gears be self-centering, under pressure, and help keep the driving shaft squarely in its bore - at least until there is significant wear of the gears and separator plate?

One problem might be that there never was a bushing for the driving shaft or - as you discovered - the Packard pump lacks an oiling channel for the driving shaft that the SBC pump has. If that channel had been there from day on, I bet the bore and shaft would have lasted a helluva lot longer - even with a sacrificial casting as it were.

As for the additional load on the Packard V8 oil pump, the vacuum pump is quite similar to the vacuum motors that drive so many air tools - just works in reverse. As such, I'm having a hard time visualizing the additional load as a problem when the pump is merely pulling only inches of vacuum - unless it is binding internally. Perhaps we ought to put a few drops of air too oil down the vac pump's intake pipe on occasion.

It's interesting to note that a 1957 Buick shop manual I have shows an oil pump with a vacuum pump riding piggyback, but that old Nailhead V8 never had the reputation for oiling issues that Packard V8 owners have had to endure. There's still a piece of the puzzle missing here that needs to be found.

One of these days, I'm gonna have to get out to the Funny Farm and my dad's old Exec (which never had a lick of oiling problems or lifter noise) and yank the engine for some serious forensic work so we can all compare notes.

Meanwhile, let's keep collecting data in this good thread.