cape dory 30 engine question

[tvangilder]

I have a cape dory 30 with the volvo md7b with a freshwater system on it that came from the factory I am told.
The dealer down the road said a few came through like that.

I took it off last weekend because access is very tough for mantainance. I was curious how many people out there have freshwater cooled md7a (or md7b) diesel verses raw water cooled.

Im in saltwater in New Jersey

[psjanker]

I have a Volvo Penta 2002 and a Universal 18, both have freshwater cooling with an heat exchanger. I viewed that configuration as a plus and would not consider going straight to salt water cooling. I suspect engine life is enhanced with fresh water cooling vs. salt.

V/r

Pete

[mgphl52]

KAYLA has a raw water MD7A. She has been in Florida waters on the east coast, west coast and northwest panhandle all her life except for a six years in Long Beach MS.

[Steve Laume]

Raven has a Universal with a heat exchanger.

One more pump and a heat exchanger seem like a small price to pay for keeping salt water out of your engine, Steve.

[Markst95]

or you could think out of the box...






http://atomvoyages.com/blog/2012.html

[Maine_Buzzard]

Shopped 10-12 boats while I was looking, and never saw a fwc MD7. I'd have suffered legions of scratches and contorted arms for one. The Volvo on Guppy was always one mishap from the bone yard. The thermostat housing perpetually leaked and the cooling pipes were jury rigged.

In saltwater, introducing raw water cooling could make life expensively interesting. Is the thermostat 140 or 160 degrees? You can run a fwc engine warmer, and salt water will scale the block with a hotter thermostat.

The MD7 was originally set up to bypass water on a cold engine, and would keep cold water flowing into the exhaust before it warmed up- It's worth checking that nothing has been blocked off to keep it from constantly running cool. If the thermostat housing is unmodified it should be OK.

Interesting threads here:

http://www.cruisersforum.com/forums/f54 ... 22461.html

http://boatdiesel.com/Forums/index.cfm? ... d_ID=55519

[Maine_Buzzard]

And the single thing on a boat that seems to be easy to get at is the host's rum bottle...

[Larry DeMers]

I also have a Raw Water cooled MD7b on my CD30. The difference here is that I sail on Lake Superior, so internal corrosion of the engine is not a worry.

In salt water, the engine will corrode quickly from the inside..in fact, down in Australia, I heard that they had a nickname for raw water cooled Volvo's ...aspirins. Leave it be, or go to another engine..perhaps a Yanmar with cast aluminum block.

Cheers,

Larry DeMers
sv DeLaMer

[JimMc]

Momentum has a Volvo MD7B freshwater cooled engine. In Sarasota in saltwater. It's original to the boat. 1983. Hull 302.