Hurth transmission help

[Mullady76]

I have a pair of ZF63A (HSW 630 actually) transmissions behind my Mercruiser 5.7’s. This morning I backed out of the slip with both engines in reverse then tried to spin the boat by shifting the port gear into forward and nothing happened. This transmission will not go into forward or reverse. The shifter on the side of the case moves but it won’t go into gear. The fluid is clean and at the correct level. Are there any sensors on this transmission that would cause this? I have a gut feeling the pump went and I’m looking at a rebuild or replacement.
Thanks, Sean

 

[alldodge]

If the dipstick has threads then its checked by not threading in.
If dipstick does not have threads then its inserted fully to check

Oil pressure should be 25bar (363 psi)
No for sure but there is a allen hex plug on the shift selector, should be able to get the pressure reading from it

Is the filter clean?

 

[Mullady76]

Thanks I’ll get a gauge and check the pressure. I did notice this transmission had a little whine when I put it in the water.