Drive Saver

[Dave Dawe]

I am preparing to depart lake Ontario and head south on the ICW this September. It has been recommended that I install a DRIVESAVER. Does anyone have experience with these? I have an M-35 in my 1991 #1159. Here is a copied description...

Absorbs vibration, reducing noise.
THE DRIVESAVER provides a flexible, non-metallic barrier between your transmission and shaft. This barrier reduces not only drive train vibration, but the transmission of vibration and noise to you, your crew and the water. Both you and your vessel are more efficient in this quieter environment

Absorbs shock.
THE DRIVESAVER effectively absorbs thrust and torque from the propeller shaft, as well as excessive shock from changing gears and high speed planing. It also helps control damage and misalignment from torsional engine movement. And THE DRIVESAVER keeps on working, under normal conditions, for the life of the drive train, with no lubrication or maintenance.

Prevents electrolysis.
THE DRIVESAVER provides an impervious barrier that blocks electrical currents from the water. Your engine and transmission are protected from damaging corrosion.

Acts as a circuit breaker.
Repeat users of THE DRIVESAVER install new ones not because an old one wore out, but because of a hidden log, line, or rock that destroyed the coupling. That's right, THE DRIVESAVER was destroyed, not the costly transmission and engine. By acting like a circuit breaker, THE DRIVESAVER absorbs the extreme shock and torque of collision, breaks apart, and leaves your transmission and engine intact. You're back in operation faster, at a minimum cost. That's the kind of total protection you can't afford to be without!

Installs easily.
THE DRIVESAVER installs simply and quickly. Without cutting or machining the shaft. And without hauling your boat out of the water. Just separate the drive flanges, insert the coupling, align and bolt.

[Braxton]

How much high speed planing are you planning on doing?

I don't have any first hand experience with DriveSaver but I couldn't pass that up.

Some of their claims seem slightly dubious.   You'll still have electrolysis issues via the raw water cooling system.   The flexible, non-metallic barrier between your transmission and shaft seems as if it would reduce fuel efficiency.

The one claim that makes sense to me is "THE DRIVESAVER absorbs the extreme shock and torque of collision, breaks apart, and leaves your transmission and engine intact."    If it can truly do that it may be worth it regardless of how dubious their other claims may be.

[Stu Jackson]

I recommend doing searches on BOTH "drivesaver" and "drive saver" - there are a few threads worth reading.

Another approach is that the keel and rudder are deeper than your prop, so what's gonna hit the prop?

[Bill Asbury]

Dave, the Drivesaver seems more appropriate for a powerboat than a sailboat, as indicated by other comments above, so I would file it in the round file and forget it.  The various drivetrains and props on power boats, including outboards, inboard/outboards and shaft drives are far more vulnerable to damage from hitting submerged objects than your C34, which ain't about to do any highspeed planing.
Cheers!
Bill

[Ken Krawford]

Dave,

I installed one of my 1988 about 15 years ago.  The bottom line is if I had it to do over, I wouldn't.  If your engine/drive shaft are out of alignment, the boat is still going to shake.
Just my 2 cents worth.

[Ron Hill]

Dave : I had a Drive Saver and it did little to nothing in the way of damping vibration.  I got rid of it and put on a flexable coupling. 
So take the $$ and go for a flexable coupling and you'll be much happier.  A thought

[Dave Dawe]

Thanks everyone - great insights and thoughts - once again proving the value of this forum!! I have so much to think about and prepare, I'll take this one off my list!

Dave

[Jimlad]

Dave, what did you do eventually regarding a flexible coupling?  which one did you choose?  and what were your experiences?  I'm considering the same route and think there may be a limited choice.  I have a MK II (1620) with an M35B and a PSS shaft seal and from what I read the only choice is a Federal coupling. 

[Ron Hill]

Guys : Those of you with a 4 cylinder M35 have a particular problem of space between the packing gland locknut and the end of the transmission. 
I'll guess that only the PSS and maybe the federal flexable coupling are "skinny" enough to fit in that small distance. 

[canuck]

If you want to plan for every contingency, you will never leave port. Pass on the drivesaver and go with a PSS seal with the vented version.
Works great and no problems after 4 years.

[Dave Dawe]

Hi Dave
I ended up taking the advice above and leaving it alone. I have been travelling for 3 months from lake Ontario to Florida and no problems.

Dave