Farymann Diesel Hydraulic Drive INFO?

[Chief Engineer]

I just came across one of these....it needs new engine mounts, that should not be a problem....I would like a source for other tech info.

[never monday]

I've seen one. I think the boat was a Carter? 30. I want to say it's a 15W engine. Might be the bigger one though. It was about 5 years ago when I messed with it.

[Chief Engineer]

I know why I got the call. The other "yards" in Baltimore don't want to mess with it.

They have parts swappers in most cases not people who are willing to troubleshoot things.

I love challenges.....that's why I love what I do.

[never monday]

what's the complaint?

[Chief Engineer]

Other than needing some engine mounts, none from the customer. (it has two "yanmar" style mounts and is missing an isolation type mount on the tail end under the pump assy...so it kind "rocks"

But I would like to know if there are any sources for info on the hydraulic drive. Just in case.

[Southern Star]

Chief, Bayfield installed hydraulic drives on Farymann diesels in the Bayfield 32 back in the mid 1970's. As I recall, the drive was not manufactured by Farymann. The swisher plates may occasionally need adjusting - again, from memory, if one ties the boat to a solid wall, you should adjust so that you reach about 3200 rpm's at full throttle. The pumps may also tend to develop leaks - if parts are no longer available, a hydraulic mechanic advised me that one could easily swap for a hydraulic drive designed for a riding mower of the same approximate horsepower.

Brad

[Stranded Mariner]

You might want to check out as well the diesel hydraulic drives that Vetus offers. Personally from an engineering point of view, I don't see the advantages of a diesel hydraulic drive system. It adds a lot of complication, and extra sources for failures.

[Southern Star]

There are a few distinct advantages, actually, if you have ever had one: firstly, it allows installation of the diesel in the best possible location in the hull and without concern about the location(angle) for a shaft, v-drive or saildrive; secondly, it allows you to move directly from forward to reverse and back without a clunk or wear and tear on gears (it is simply a valve that reverses flow of the hydraulic fluid); thirdly, it permits you to dock at a constant rpm and to increase or decrease the power to the propellor through gradual engagement/disengagement of the hydrualic drive.

Brad

[Chief Engineer]

Just finished putting a missing vibration isolator in....Put the right belts on....checked hoses....engine runs smooth....has a good bit of thrust....but probably not enough to get it up to hull speed.....

Oh and did I mention I had to hang like a bat and cram into a hole at the same time.

Thank God it wasn't 90 today.

(That's why we get the "big bucks" [bruises, cuts, scrapes, and pulled whatevers])

[clausont]

I would like to know more about this. I am not sure that my old Nanni transmission is all that good (somewhat noisy) and if I have to replace it at some time, I would be interested in installing a hydraulic drive.

[Alan Wheeler]

secondly, it allows you to move directly from forward to reverse and back without a clunk or wear and tear on gears

Not entirely. The big issue with Hydraulic is that you can twist or shear the shaft or Prop. There are no "soft" stop-start's. Of course on smaller systems, it is not likely to cause a problem, but the bigger the Prop, the more possible damage.
The big negative with Hydraulic is the tremendous loss of energy. It takes effort to move oil through hoses and Hyd.motors and pumps and valves. It also takes a lot of energy to turn the pump and the Hyd.motor just on their own. The result is about 50% of the Diesel motor power goes into just running the hydraulics themselves.
Plus to get the best most efficient power from a Hydraulic system, you really need to run the Diesel motor at full RPM.
Then to add, the noise from Hydraulics is quite high.

[Chief Engineer]

That's funny...I didn't find the noise to be that much different.....

[wlupton]

I have one of these monsters in a Morgan 33 from 1974.
How do you adjust the swisher plates?

[Chief Engineer]

What is a "swisher plate"?

[S/V Antares]

The throttle can be variable or FWD/Reverse depending on the type of valve used. not uncommon in Europe. You can add thrusters and other gadgets if you have a good system. Camper Nicholsen made a few boats that way.