oil pump seat repair

[Guest]

Is there anyone I can send my 58 pan oil pump to that can recut the check ball seat? I have tried lapping and burnishing without any luck. If not then I will have to try a new replica pump from J and P. Does anyone have experience with one of these replica pumps? Are they any good? Thanks.

[T. Cotten]

Dustydog!

I have no experience with the 'replica' pumps, but I do have experience working with the original seats, and not always good experience.

Once upon a time, I dreamt up "burnishing" the seats, and produced a tool for it. It turned out to be a disaster, as the variety of pump casting materials proved some to be hard "chilled", and the burnisher suffered as badly as the pump. So I have dis-avowed the practice.

Once I began bubble-testing the seats on the bench at very low pressure (first attachment), I soon found that any practice of cutting, lapping, burnishing (second attachment), or punishing with a drift only made a simple flat-grind from the top much worse. The stone on the right in my second attachment, piloted of course, did best.

Tragically, the threads for the cap are rarely centered upon the hole below it, so no piloted tool is usefull except the flat-faced stone.

I doubt the factory's seat was much better.

....Cotten

[Guest]

Can I send you my pump?

[T. Cotten]

I had hoped I discouraged that, Dustydog!

My shop is only accepting established carburetor service accounts, and float and manifold service requests.

If anybody at all wants to step up to the plate and bat at this pesky problem, I'm here to support him/her!

....Cotten

[Guest]

Well thanks anyway Cotton. I appreciate your response. Anybody else know of a place that fixes these pumps. Surely someone has bought one of the aftermarket pumps?

[MMasa]

Cotten
Ever try it with a solid carbide ball bearing on the burnishing end?
Mark

[T. Cotten]

Mark!

Bubbles don't lie...

Once again, the variety of castings is the issue.
Aluminum bodies were most successful for 'burnishers', but chilled castiron would spall and fracture with any attempts.

My losses were heavy, and I can only suggest avoiding anything other than the factory probably provided: a simple hole with a very sharp edge, with no pre-formed seat at all.

As most know from cutting other valve seats, the narrower the better for a seal. There is no need here for heat transfer like a cylinder head.

....Cotten

[Steve Little]

Hi Cotton. Your Gyro Gearloose when it comes to homemade tools .
When you made the burnishing tools, did you send them for case hardening?
Maybe a fine diamond coating.
Any old HD dealers or mechanics (Robbie) that can recollect or heard stories of new Pan heads or early generator Shovels leaking on the showroom floor.

[Rollo]

Send it to Paul Friebus at American Cycle Fab in Bloomsburg PA he does it. He has perfected the oil pump son old HD's. His add is in the club magazine.

Tom (Rollo) Hardy
AMCA#12766

[Guest]

I know of that shop. I'll give them a call. Thank you very much.

[Guest]

Even if I could just slow the leak down would be an improvement. This one really leaks bad. Worse than Trump's White House. Thanks again.