[firstlight]

I recently purchased36 ft. Open with qsb 380 Cumins. The boat has ZF transmissions.
When in gear at low rpm transmissions whine, but operate fine. Is this normal?

[momentum]

Hydraulic pumps can whine , check oil , watch temps and pressure . Run it like you stole it !Also consider is your turbo talking to you or the gears ? I have a mack which has a turbo whine so loud you look for sirens ! Somewhere along the way the wrong oil may have been added . too thin ,So if your scared do a service . My zfs use straight 30 motor oil with spin on filters . Trolling valves may also play into it . My express does not have them . So I can't really comment on those ,I do know that they allow slower speeds ?

[Jeff]

Sorry to say this, but I'm glad to see this post. I have a 36 Sovran with 450c's and ZF transmissions. We just finished our second season with it and I started noticing early this season that I have a whine at low rpm's. It's more noticeable around the harbor, for example, with the quieter surroundings. I've lifted the day hatch to the engine room and the trannies are right there and I can't hear anything that makes me nervous. I changed the oil (straight 30w) when we bought it and check it regularly, and it's still perfectly clear. Let us know if you learn more!

[trit21]

You may be able to find some information on boatdiesel.com. I remember someone there mentioned that whine is fairly common with these trans. I have zf 220a trans and slight whine maybe but hard to tell really since all the noise has been there since I bought boat 2 yrs ago. 2000 3500 cummins power

[CAPT. JEFF]

I learned today that the whine in my ZF, while in reverse, is perfectly natural and expected. However, a forward gear setting, the whine could be oil pump. I was told to change oil and filter before going deeper. Boat is on the hard for lots of other problems, but will post with outcome.

[Vic]

I own a 2002, 3100 express with Cummins M1.0TA (6BCTA) motors and ZF transmissions.
I am having trolling valves installed.
My mechanic and I are having a hard time deciding how to control the valves at the helm. There is limited space.
An suggestions?