Boundary pump gears showing galling
 

I’ve had my engine out for rebuild after a persistent rear main leak and loss of compression. The engine had dyno tune hours only.

The engine builder is checking everything and he sent me photos of the boundary oil pump gears yesterday which are showing galling along one side of the meshing face of the gears. On measuring he has found that the gears are tapered by about 2 thou and this is resulting in contact and the galling. Has anyone encountered this with Boundary?

https://cimg8.ibsrv.net/gimg/www.mia...aac8102b6.jpeg
https://cimg9.ibsrv.net/gimg/www.mia...d4375516a.jpeg

I had a similar issues when i was rebuilding my engine. I got a brand new boundary pump and when I installed it and was turning the engine by hand, I noticed that there was a tight spot. Thankfully I noticed before I started running the motor, so I sent it back to boundary and they sent me a new pump. I checked everything on this one and it seemed to be working just fine, and after 2500+ miles its given me no issues.

here the photos of the imperfections on mine.
https://cimg1.ibsrv.net/gimg/www.mia...4b5d96d69f.jpg
https://cimg2.ibsrv.net/gimg/www.mia...9682dc8652.jpg

What are the main bearing clearances?

While boundary issues aren't unheard of, the oil pump is also one of the first things to be damaged by debris and other rotating assembly issues. That gear definitely needs to be replaced, but I'd have a hard time telling you if it's a machining issue.

They are now .002 I don’t know what they were before.