Pulled the pump off the bike, cleaned and rebuild. Used the following to re-seat the check ball. http://www.bigboyzheadporting.com/showthread.php?t=87.

I did notice my “Bypass valve spring plunger” was not so smooth anymore (did not mess with this at all) – upon re-assembly, I lubed the port and inserted the plunger, it felt like it got binded up, removed & cleaned, and did again – same thing, third time after another cleaning – was smoother, but still did not feel right. I tested each spring by reassembling and holding the spring down with oil filled in cavity – on the plunger side, a little drop or two would leak through the body – sure much more when real pressure is going! Check ball was perfect, nothing came through. I put it back together, and on bike. Checked all lines four times to correct routing (Filter hoses such a pain to remember where they go (on return)) started bike and everything flowed as it should. Crap load of oil came out of the sump, as expected – BUT here is where I am having an issue, the bike was all set, cleaned up and figured job well done – next morning I came out, I had a pond of oil under the bike (6’ X 3’) spot! What is going on! Pump was fine, noting through the seals, it all came from the sump breather hose.

So I took the pump off once again, cleaned and double checked that the right springs were in the right spaces, put it back together, made sure the check ball was in, nothing missed – put back on the bike, triple checked hoses once more – all look good. Second night, another drain out – this time I had an oil pan to catch what looked like two quarts at least!

What did I miss? Now I am thinking I did not seat the seal on the drive shaft correctly on the re-build, or it is that “Bypass valve spring plunger” – what could it be?

Shopping for a new oil pump now, but don’t want to spend the big bucks on a S&S, so options are RevTech, Sifton and the Ultima – with a lot saying Ultima is a good product.

Anyone come across this before? Any suggestions?

 

the ball check is the cork for the engine so to speak - it allows oil to come by like a one way valve when its bypassing, and when its not the spring is susposed to stop the oil from sumping - yours is not -- what exactly did you do to RE SEAT the ball

every once in a while someone brings in a pump they re seated, and to my eye it looks to be the seat in the ball area is NOW cracked -

very carefully look at that area for a crack around the seat

 

The " be careful and give it a few lite taps on the punch " usually ended up being whacked hard enough to rock the bike . Got a few trashed pump bodies making homes for spiders in the shed .

Here's my version of a pump check ball reseat .

https://www.hdforums.com/forum/tech-...ll-repair.html

 

love that tool you made //////////////////// mine is a lot less low tech - nothing more than a steel rod with a pump ball welded to the end --