Water in transmission AFTER riding 05 EC 250

[Alejandro]

Hello, I am new to this forum. I have a 2005 EC 250 I bought in 2008. I love the bike, but I"ve been having a weird problem.
I get water in the transmission after I ride.
I changed the seal several times, then I go ride all day without any problem, when I put the bike back in the garage, next time I look at it, there is water in the oil.
I use automatic transmission fluid in my bikes, and I am happy with it.
But this issue has me very confused. I already changed the water pump seal a few times (4 I think).
I thought I could have a compression leak so I changed the cylinder head o-rings too.
I am very puzzled because the issue normally happens after I ride. Thought once it happened while riding.
Has anybody had this problem or heard of it?
Thank you,
AL

[(F5)]

Yes. You need to change the pump seal. . . and the shaft. It is quite cheap but have a look at it close. There will be pits. That roots the seal.

Some preloaded the seal a bit with a thin washer like a suspension shim.

When changing the oil pour a litre of diesel in it and run the bike carefully on a stand in in gear for a few seconds. Drain and repeat. The diesel picks up the water.

[Alejandro]

Thank you for your fast reply.
I have already replaced the pump shaft too, and I got the same problem. My bike already came with the shim for the water pump, so I kept using it even though it was not in the parts manual.
I have a new shaft I can replace again, but I just installed my last seal, i will have to order a new one again! Parts for these bikes got so expensive in the last few years!
Thanks again.

[Zman]

I have seen some cylinders that had thin castings near the water port where it mates to the cases. It may be worth a look to verify it is not leaking between the cylinder to cases or between the outer clutch case and inner case.

[gasgasman]

Also, double check the seal orientation.
You should not have that many leaking.