Volvo Penta Page

Volvo Penta Composite Drive
Finally Steps from the Shadows?

1 Sept. 2001

Possible Composite Drive Patent?

Composite gear cases were thought to be limited to belt or chain drives due to the high tolerances required in properly meshing the gears in todays drives. An Oct 1999 Volvo Penta patent (U.S. Patent # 5,961,358) by Jeff Hardesty and others, titled Reversible Stern Drive Marine Propulsion System, appeared to use chain or belt drives and hinted Volvo might be thinking about a composite case. The patent included the quote, "continuous drive member removing close tolerance needs of conventional stern drive gear case."

First Release to the Press

They briefly exposed (then retracted) the XDP-Composite drive to the press in late 2000. One of the initial sketchy press reports remains online. Some reports were said to be removed at the request of Volvo Penta.
It’s show time for power boaters
Power Boating Canada
Vol.15. No.6. Dec 2000.
The new drive was anticipated to be much lighter in weight, have improved corrosion resistance and drastic reduce assembly time.

Wins Composite Fabricators Association ACE Award

While Volvo was trying to keep things quiet, the drive won the Composite Fabricators Association ACE Award (Awards for Composite Excellence) in the Market Expansion category in September 2000. The awards page describes the collaboration required to develop this compression molded composite marine stern drive propulsion system and how this new, virtually all composite product replaces all old metal (aluminum) technology products that have been the industry standard since engine powered boating became a reality.

The new drive and mounting system improves impact resistance, corrosion protection, environmental friendliness, styling and performance. Ultra high tensile and flexural loads (unmatched by any other known compression molded product, as high as 90kN) were accommodated by innovations in design, mold and assembly tooling and materials development.

The use of matched metal tooling to mold the side panels of the drive, with high strength Dexter adhesives allowed styling and hydrodynamic improvements in shape to optimize performance.

The unique mold was designed by R & R Tool allows for successful molding of extreme thickness cross sections not usually seen in compression molded products. The high heat tolerance of the ESC formulation allows the material to form exhaust gas passages for the internal combustion engine absorbing noise and allowing an integral underwater exhaust.

Exhaust systems features include, anti-corrosive properties and the nearly dry sump oiling system to help eliminate possible oil and metals contamination to boating waters. The drive reduces part count in design and approximately a 20 percent decrease in weight. Primary suppliers are: Quantum Composites, Inc. InnoTech Industries, Inc. R&R Tool and Mold, Inc. and Dexter Corporation.

Wonder if Volvo Penta knew so much technical info would be released when the applied?

2nd Release to the Press?

The August 2001 issue of Go Boating has a sneak preview of the Volvo Penta Ocean Series XDP composite drive on Pages 34 and 35. They say it will be available in both diesel and gas versions and offer unmatched durability, strength and corrosion resistance in salt water applications. It out performs aluminum drives in fuel economy, handling, durability and service.

The drive has fewer joints and gaskets than aluminum drives and weighs about 40 pounds less than conventional drives. The drive profile provides improved hydrodynamics and reduces drag 10 percent while providing better steering control and maneuverability (and includes stronger gears than previous models). It has nearly 30 percent fewer components and more efficient exhaust passages (less back pressure). It also has improved water circulation (91 liters/min vs. 60 liters/min).

Specific engine packages will be:

The drive will accept composite or steel propellers and should be debut this summer. No information on the drive is currently available from the Volvo Penta or Fluid Thinking ( Volvo Penta press) sites.

Intellectual Property

Wonder what kind of patents are being filed by Volvo and its collaborators in this area?

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