Hurth Shift valve testing

[Hy Pryluck]

A few days ago, I was coming into the marina’s channel to get to my slip. All was fine till I wanted to turn to starboard. I put the port transmission into reverse from forward and nothing happened. Neutral. I put it back into forward and it stayed in neutral. After some piling bumping and help from the dock crew, I got into the slip. Removed shift cable from transmission and shifted manually; stayed in neutral. Transmission fluid is clean, with no particles or burnt odor. I was told the shift control valve must have failed. Since this part is over $1000, I’d like to test it, either on the transmission or on the bench, to be certain it went bad. I used to do that with car shift valve assemblies, but don’t know if or how I can do that with a Hurth marine transmission. Any help or guidance would be appreciated. Transmission is a ZF631 V1. Thanks. Hy

Topic

[Hy Pryluck]

valve testing

Thanks, Steve. I’ll relay the info to the mechanic and do some testing myself, following your directions. Hy

[Tony Athens]

1st thing I’d do is see if the gear is turning the pump.. Maybe a total drive plate failure?………………………………….Install a pressure gauge?………………….Remove the pump assembly and crank the engine without letting it start and see if the main input turns?……………..

Tony

[Author]

Replies