Oil Pump Leak Questions, Normal wear, or....? Options

[BeatNavy]

I've had a couple of oil leaks on my fresh 2270, the most annoying of which seemed to come from the area of the oil pump and gradually got worse. Oil would drip on the underside of the engine mount cross bar in the center and air flow would then scatter it around (on engine, gearbox, exhaust, etc.). I bit the bullet this weekend and pulled the engine.

I then pulled off just the oil pump cover. I gather it's best to leave the pump housing itself in place if that's not the issue. I've got pics below showing where the lower oil pump gear has really ground against the cover, and a closeup of the gear itself showing wear on the gear. That edge on the inside lip of the gear is actually sharp to the touch. I would be guessing that metal on metal contact is not awesome right in the heart of the lubrication system, but I have also heard that those pumps do press against the cover.

Not sure if this is the cause of, or contributor to, my oil leak, but how does this look to the braintrust? Assuming this is considered "acceptable," any tips for sealing this bad boy up so it doesn't leak? I've seen McMark's video....

Here's a shot of the pump with the cover on. Oil can be seen collecting at the bottom on the lip. If I had to guess it looks like it actually came out around the studs, as the nuts were pretty oily on the inside.



Cover showing wear...



Oil pump gears....



Closeup of the bottom gear. It's actually worn a sharp lip on that lower gear.

[BeatNavy]

Ok, so the pump housing came off the case easier than I anticipated. I compared the old with the new. One thing that jumped out at me is that the idler gear pin seems to sit proud of the back of the pump housing on the old one. Here's a comparison:

(taken with my wife's iPhone 12 pro, with amazing resolution. Unlike my iPhone 6 which makes every picture look like a vintage loch ness monster pic)

Old pump with idler gear pin sitting proud:


New one from type 4 store:


I took a look at the old and new covers. For some reason on the new one from type 4 store they really got aggressive cutting off the corner on the one side to make it clear the case. They didn't leave as much "meat" on there as I would like. So I sanded down most of the galling on the old plate and I'm thinking about reusing that. I exchanged emails with John at the Air Cooled.net and he thought the cover was reusable if I ground out the galling. Hopefully I smoothed out the galling, while still leaving grooves for the Loctite 518 to bite into.

Here's a comparison of covers (taken with iPhone 6):


Just kidding, here it is with new one on top, old one on bottom. Took a lot off that corner when I don't think it's necessary to be that aggressive.


Anyway, about to install the new pump. Hopefully all good.