Volvo Penta 10A Cooling Problem

[Richard-R]

Hi,

I'm bringing back a Cal 2-27 to sailing after it has sat for a few years. We had problems starting the engine, a Volvo Penta 10A, but after a couple of days of work and replacing numerous small parts finally got it going.

However we only ran it for a minute or so as we're not sure of the following, and I can't speak to the previous owner to ask... There is a two way cock on the top of the cooling system that holds the thermostat and distributes the water for either A. Set for dry exhaust. Or B. Set for wet exhaust. It is currently set for dry exhaust.

I am unable to talk to the previous owner but the motor had been drained and left for winter (impeller out and drains opened,) so the cock could have moved/left for winter or.... the question is how can I tell if this motor has a dry or wet exhaust?

And, if I run it with the setting wrong what can happen?

Thanks for any help,

Richard

[Lepke]

A dry exhaust is insulated and goes out thru a stack or above deck pipe. A wet exhaust exits thru the hull, usually the transom and the water raw water is injected into the exhaust stream after the exhaust manifold into an elbow and carried away with the engine exhaust.
If you put water into a dry exhaust, you'd have hot water and soot coming out the pipe. When shutting down, the remaining water in the dry exhaust would flow into the engine cylinders.
If you fail to put water into a wet exhaust, the lack of cooling would probably cause a fire.

[a64pilot]

If there is rubber hose connected to the exhaust system and if the muffler is plastic or fiberglass, then it's a wet exhaust.
Dry stack, think over the road truck exhaust or go look at a Commercial shrimping / fishing boat etc.

I've never seen a dry stacked sailboat, but anything is possible I guess

[DougR]

The MB10a was designed for use with either a dry exhaust or a water cooled exhaust, hence the valve located on the top of the thermostat cover. If the valve is turned to the dry exhaust position, the cooling water will be directed out of the hose nipple directly adjacent to the valve, and no water will travel thru the exhaust. If the valve is turned to "wet exhaust", the cooling water will be directed thru the metal pipe to the exhaust manifold and then travel out the exhaust pipe with the exhaust gasses.

As mentioned by a64pilot and Lepke, you will have to determine which system you have. That said, I would be very surprised if your Cal 2-27 has a dry system.

DougR

[DougR]

For more info on your engine go online and visit "marna.no". They have parts, manuals, etc.

DougR