What About a V Drive?

[David M]

Really goes to show that no propulsion system is perfect. There is always a compromise somewhere. Pick your compromise and live with that.

[SkiprJohn]

And Kassel v-drives might be spelled Cassel or some other way. Again, I can't remember.
Regards,
JohnL

[TOM]

I have a Borg Warner with a Haynes and Hellyer V Drive. Motor is a Brittish leyland 60 hp fisherboy all original 31 YEARS OLD !.Motor was recond in 2001 the whole thing just purrs along and is so compact . Like everything if its professionally installed it will be fine

[pbutler]

I've got pretty much the same setup as MainSail: a Westerbeke 27 with a Hurth V-Drive and a PSS shaft seal. I'll echo his comments about the value of a dripless, adjustment-free seal if you've got a V-drive.

While both a traditional stuffing box (which admittedly has both strong and weak points) and a dripless, PSS-type seal both require frequent inspection, the PSS seal is essentially maintenance free. V-drives make wrenching on your stuffing box a chore; a PSS is a natural choice in this case.

There's one positive feature of a V-drive I haven't heard mentioned here: they give you the option of removing the shaft without removing the shaft coupling. See that cutout in the floor in front of the shaft? If you unbolt the shaft coupling from the transmission output flange, you can pull the shaft *into* the boat (provided you have removed the prop, zincs, etc).

On an older engine installation, removing the shaft coupling from the shaft can be a real chore, and you have to send it out for a fit & face before you re-install it. Pulling the shaft into the boat can save you this trouble.

[btrayfors]

V-drives have been around for ages. They are very reliable. I had two on a houseboat for 17 years. I have had one on my sailboat for 20 years. I have serviced V-drives on other boats. Mine were Walthers...excellent pieces of gear.

All a V-drive does is allow you to place the engine further AFT than you otherwise could. It reverses the direction of the shaft coming out of the engine/transmission. You simply turn the engine around "backwards" and couple it to the V-drive. Then, a regular shaft extends from the V-drive aft thru the hull to the cutlass bearing, strut, and propeller.

Depending on the design, some boats need a V-drive in order to accommodate an engine, without having it sit in the middle of the cabin.

Bottom line: intrinsically, they're neither good nor bad. They're simply a necessary piece of gear on some boats.

Are they better than Sail Drives? Notwithstanding the apples and oranges comparison, yes, you better believe it!

Bill

[Jim Cate]

Another reason to not use sail drives on a cruising boat, mono or multi: when (not if...) it crashes, you must remove it from the boat to service it. This makes a big hole in the hull, so it is better (!) to do it on the hard. If you are in, say, northern Vanuatu, or maybe the Louisiades, or any other bit of the woop-woop, getting the boat on the hard ain't easy.

At least with a conventional drive,or even a V-drive, you can get it out to work on it whilst still afloat.

I wouldn't consider a saildrive on a cruising boat nohow, noway!

Cheers

Jim and Ann s/v Insatiable II lying Gladstone Qld Oz

[redcobra]

I have a Walter's v-drive on my boat. Works great, easy access.
Uses HD30 oil and has a water passage for cooling.
New Page 2
Pictures on request.

[scrumble]

Originally Posted by pbutler

I've got pretty much the same setup as MainSail: a Westerbeke 27 with a Hurth V-Drive and a PSS shaft seal. I'll echo his comments about the value of a dripless, adjustment-free seal if you've got a V-drive.

While both a traditional stuffing box (which admittedly has both strong and weak points) and a dripless, PSS-type seal both require frequent inspection, the PSS seal is essentially maintenance free. V-drives make wrenching on your stuffing box a chore; a PSS is a natural choice in this case.

There's one positive feature of a V-drive I haven't heard mentioned here: they give you the option of removing the shaft without removing the shaft coupling. See that cutout in the floor in front of the shaft? If you unbolt the shaft coupling from the transmission output flange, you can pull the shaft *into* the boat (provided you have removed the prop, zincs, etc).

On an older engine installation, removing the shaft coupling from the shaft can be a real chore, and you have to send it out for a fit & face before you re-install it. Pulling the shaft into the boat can save you this trouble.

Good Day All,

Please excuse me for using this thread to ask a question regarding the correct way to fit coupling to shaft for a ZF 15 MIV (new number/name for the Hurth V drive mentioned by PButler above and the same as the red gearbox photos in Maine Sail's post).
So far, what I have seen appear to be like a straight shaft arrangement, not tapered for the thrust, seemingly with the thrust transferred through the set screws???.
Please tell me that I have got this wrong and that something like a shaft taper or internal flange within the coupling is used.
The photos of an install in this forum and the two new engine /gear boxes I have awaiting installation are the sum total of my knowledge regarding fitting this coupling.
Thank you for your consideration.

Regards

[Cheechako]

I've had Hurth V drives in a Passport 47 (90 HP Mercedes) and Lagoon 42 Catamaran. Never had any problems at all. Amazing how small those trannys are. The shaft exposure from the stuffing box to the transmission on the Passport was awful short making stuffing adjustment a little hard.... but all in all.... it was forward of the engine for access instead of standing on my head under the cockpit!

[scrumble]

Good Day Cheechako,

Do you have any idea of how the shaft/coupling interface was handled?

Regards,

[pbutler]

Tom,

You don't have it wrong--there's no taper at the coupling end. But there is a key and two beefy set screws. Yeah, that seems kind of weak, but it seems to work fine.

[Cheechako]

Tom, not sure what the question is.... but it was just a simple keyed/flanged coupling maybe 10" (?) in front of the stuffing box on the passport/mercedes. The Lagoon had a lot more exposed shaft which is probably a better situation... theoretically! I will say that the Passport had very little stuffing box leakage problems. The Mercedes was a great diesel but had an inherent vibration at low rpm in or out of gear though.... kind of a harmonic thing.... I always worried about the limited ability of the shaft to flex with engine movement on the mounts due to it being so short.... but it worked... The Hurth V drives I had were not cooled.... the one in the Mercedes would get so hot you could fry eggs on it!.... but it was 10 years old when I got and kept going....

[scrumble]

Thank you all, your input has been most helpful.

Regards,

[Laidback]

Very reliable drives - not unusual to find many still functioning as good as new after 30 years :-
Red arrow shows connection to the engine and blue arrow connection to prop shaft.

[macbeth]

Originally Posted by pbutler

There's one positive feature of a V-drive I haven't heard mentioned here: they give you the option of removing the shaft without removing the shaft coupling. See that cutout in the floor in front of the shaft? If you unbolt the shaft coupling from the transmission output flange, you can pull the shaft *into* the boat (provided you have removed the prop, zincs, etc).

I have a 1988 Niagara 31 with a 30HP Diesel v drive, Hurth transmission. The stuffing box was re-stuffed in 2000. I think it's time for a change and the 1988 "connecting" hose attached to the stuffing box looks like it should be replaced as well.

Can I really pull the shaft inwards ? I would never have thought of that ! The shaft is keyed into the coupling at the front with two bolts screwed in the side, connected by twisted wire. Do I need to take that coupling off first ? In fact, if someone has the time, I'd love some instructions on how to do what I'm contemplating, as I've never done it before, and probably will never do again !

Finally, is the PSS still the best ? Thanks.