Three's not a crowd for a North Charleston-based marine propulsion business.

Cummins MercCruiser Diesel, a joint venture between two well-known engine makers, is welcoming another blue-chip name to its local manufacturing partnership.

Starting Jan. 1, all Volkswagen boat motors will be marketed, distributed and sold under the Cummins MercCruiser Diesel name. Also, the local venture will help the German automotive giant in developing new diesel-power marine engines of up to 350 horsepower that will comply with future emission standards.

Based on Leeds Avenue, Cummins MercCruiser Diesel is an eight-year-old joint venture between Columbus, Ind.-based Cummins Inc. and Mercury Marine of Fond du Lac, Wis.

The companies make several lines of heavy-duty diesel boat engines together. Cummins MercCruiser employs about 135 workers at the local factory.

Clay Gaillard, a spokesman for the North Charleston plant, said it's too soon to tell whether the VW deal will yield any more jobs for the area. The new line of engines will be made at Volkswagen Marine's 7,000-worker plant in Salzgitter, Germany.

But Gaillard stressed that the long-term venture enhances the Leed Avenue operation by bringing in a line of business tied to a high-profile global manufacturer.

"It's certainly a good thing for CMD, and it will certainly go toward our long-term health," Gaillard said. "This offering is not supplanting anything we make in Charleston here today."

He noted that the locally based Cummins MercCruiser engineering division will be involved in the design of the new engines. The local plant also will take responsibility for service and handling of warranty claims for motors sold previously under the Volkswagen Marine name.

"Our people here in Charleston will be working hand in hand with the Volkswagen folks in Germany to develop this next generation of engines and to fully integrate the current engines in the CMD portfolio," Gaillard said.

Reach John P. McDermott at 937-5572 or jmcdermott@postandcourier.com.