Hi everyone,

I have a problem regarding my Merctrans II Transmission. I had a leak coming from the input housing. (the big O-ring)
Now I rebuilt it and renewed all the gaskets with an original seal kit. I also replaced the old clutches and plates with new ones and cleaned everything up and sealed it real tight.
Running on ATF Type A.

I've put everything back together in the boat and let it run on the waterhose. Engine ran good and also the transmission shifted forward, back in neutral, reverse and back in neutral.

I let it run for about 10 more minutes, but then the problems started: It would shift in forward, back in neutral, in reverse, but from there on it was stuck in reverse.
If I now shifted back in neutral nothing happened. If I put it in forward from there the engine stalled.

When I fired the engine back up, it was in neutral again!?

What could be wrong?

What I don't get is that it worked normal for the first 10 minutes.

- too much or too little oil? (dipstick reads "full")
- reverse band adjustment? (tried to turn it out bit by bit, but nothing changed)

Every help is apprechiated! Thank you!

Okay, so I try to exchange the control valve housing now. I hope that the valve maybe is blocked in either way and that it will work then.

One more thing came to my mind: Does the prop need a certain resistance from the water for the transmission to shift out of reverse? Could that be a plausible explanation?
Maybe it just does not work on the trailer with a hose attached.

Maybe I will try it again with the drive in water.

I you have other ideas please let me know.

hoping BAM could chime in !!!

Okay, so for those who have a similar issue: We initially used some sealant with the gasket on top unter the valve housing.
This sealant went into one of the oil-canals and blocked it... pretty dumb story haha.

I cleaned everything up and we ran it again. Everything worked as it should.

But you can be sure that the oil flow is blocked somewhere if you have the same problem.