Sunday, March 14, 2010

Drivetrain Options......

On my last boat I installed a Vetus Bullflex between the shaft coupling and the transmission. It worked as advertised. However, the $900 price tag seems a bit steep.

Another option that I think is interesting is the "Powertrain Marine Joint".


robert said...

That powertrain joint looks similar to AquaDrive and PythonDrive yet doesn't require a separate thrust bearing. I wonder how the stresses from misalignment would affect the transmission? May not be a big deal for <100hp. And may depend on the quality of the transmission.

Ocean Dove said...

On Ocean Dove I am installing a R&D flex coupling and a Buck Algonquin Split Coupling.
Check them out

The Incredible Hull said...

Thanks for the comments guys. I have always lusted after the Aquadrive but I was not about to spend weeks head down in the aft bilge glassing in a bulkhead. The Powertrain Marine Joint looks interesting and at $600 is not completely nuts. Part of the logic is that my existing shaft is too short for a direct connection so I will have to buy a new one if I go the R&D flex coupling route. So cost of new shaft + cost of R&D Flex might take a big bite out of the Powertrain Marine Joint (this is 7.6 ins long). Sad logic that we boaters use to justify squandering money. The jury is still out.

Ocean Dove said...

If a weather window arrives next week (no snow or rain) I will cut open the shrink wrap and install the new engine. The shaft on Ocean Dove was in bad shape with wear and corrosion.
I am replacing the complete drive train prop, shaft, stuffing box, cuttless brg. coupling, after 24 years it is do.
If your old shaft and coupling are in good shape but 7.9" short you may consider installing a short "Jackshaft" (7.9" long) with coupling on each end one to match the old shaft coupling and one for the new gearbox. The extra cost would be for 7.9" of shaft and a coupling.

Ocean Dove said...

I have been pricing a new shaft of Aquamet 22 prices vary form $600 to $1600 for a 1.25 dia. x 69" shaft.
the R&D flex coupling $134, B-A coupling $79, Cambell Sailer Prop. $785, C-Brg. $40, stuffing box $40.
cost new shaft and coupling
total drive train cost $1678
there are some taxes,shipping cost and misc. items Hose clamps ... but with every thing new for less than $2000, Maybe it will last another 24 year.

Regards Derek
Ocean Dove

The Incredible Hull said...

Thanks Derek, great info. I think the shaft is OK, I had it checked before launch. I never heard of a "jack staff" but I will investigate. Interestingly the shaft on TIH is 1.5 ins.