Volvo MD7A

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Judy Clasen

Volvo MD7A

Post by Judy Clasen »

I'm a first time visitor to this Great web site. I'm seriously considering the purchase of a CD30 that has a raw water cooled Volvo MD7A (13hp). After mastering the servicing requirements of my Universal 14hp fresh water cooled diesel, I'm a little concerned about the reliability/problems associated with raw water cooled engines. Do most CD30's have Volvo's with raw water cooling? If anyone can help ease my doubts I would really appreciate it. Also if anyone in the Bay Area is interested in selling their CD30 (Alberg designed, cutter rigged) please contact me via email.

Thanks and Happy Sailing



rwjeepster@aol.com
David McMurray

Re: Volvo MD7A

Post by David McMurray »

Judy Clasen wrote: I'm a first time visitor to this Great web site. I'm seriously considering the purchase of a CD30 that has a raw water cooled Volvo MD7A (13hp). After mastering the servicing requirements of my Universal 14hp fresh water cooled diesel, I'm a little concerned about the reliability/problems associated with raw water cooled engines. Do most CD30's have Volvo's with raw water cooling? If anyone can help ease my doubts I would really appreciate it. Also if anyone in the Bay Area is interested in selling their CD30 (Alberg designed, cutter rigged) please contact me via email.
I am also looking at a CD 30 for sale and have the same concern about the engine. I have heard it is an expectation to have to replace the 13 hp. I am new to the diesel engine world and need seasoned advice.
Judy Clasen wrote: Thanks and Happy Sailing


dmcmurray@flinteng.com
Jon Larson

Re: Volvo MD7A

Post by Jon Larson »

I've got a raw water cooled MD7B in my 1981 CD30. Except for wearing out impellors and a couple of water pumps, the engine has been exemplary. Oh, I did have to clean out the thermostat a couple of times.

PERI spent most of her life in fresh water on the Hudson River with cruises down to the salt water. It's only the past couple of years that she's been in salt water on a regular basis, but I don't think that should affect the basic engine reliability.

I have followed the recommended oil and oil change religiously, I think that helps.

Jon Larson
Cape Dory 30 PERI
San Francisco Bay
David McMurray wrote:
Judy Clasen wrote: I'm a first time visitor to this Great web site. I'm seriously considering the purchase of a CD30 that has a raw water cooled Volvo MD7A (13hp). After mastering the servicing requirements of my Universal 14hp fresh water cooled diesel, I'm a little concerned about the reliability/problems associated with raw water cooled engines. Do most CD30's have Volvo's with raw water cooling? If anyone can help ease my doubts I would really appreciate it. Also if anyone in the Bay Area is interested in selling their CD30 (Alberg designed, cutter rigged) please contact me via email.
I am also looking at a CD 30 for sale and have the same concern about the engine. I have heard it is an expectation to have to replace the 13 hp. I am new to the diesel engine world and need seasoned advice.
Judy Clasen wrote: Thanks and Happy Sailing


jon9@ix.netcom.com
John R.

FRESH WATER MD7A

Post by John R. »

Judy Clasen wrote: I'm a first time visitor to this Great web site. I'm seriously considering the purchase of a CD30 that has a raw water cooled Volvo MD7A (13hp). After mastering the servicing requirements of my Universal 14hp fresh water cooled diesel, I'm a little concerned about the reliability/problems associated with raw water cooled engines. Do most CD30's have Volvo's with raw water cooling? If anyone can help ease my doubts I would really appreciate it. Also if anyone in the Bay Area is interested in selling their CD30 (Alberg designed, cutter rigged) please contact me via email.

Thanks and Happy Sailing
We have a '83 30 foot cutter with a MD7A. I'm actually surprised to hear that some thirty footers were furnished as raw water cooled. Our
MD7A has fresh water cooling from the factory. It is comprised of a heat exchanger made by Sendure Products, a Jabsco pump mounted on a plate in front of the thermostat housing with a second belt running to the alternator, and a Sendure coolant resevoir / expansion tank mounted inside the starboard cockpit locker, a few extra hoses and thats it. I had a Island Trader ketch with a 30hp Yanmar that was raw water cooled and never had problems with cooling. I always kept an eye
on the engine zinc condition, and changed them when they were down to fifty percent of their original size. The MD7A doesn't have zincs in the block or cooling system that I'm aware of. The service manual also
does not show any in that engine. My Sendure heat exchanger has one in the bottom of it for the raw water side of the cooling system. I can't imagine any MD7A's that are raw water cooled without a zinc fitted somewhere in the cooling system, if not, it's a formula for destruction to that sweet little diesel. If the boat your looking at is raw cooled as you mention and you can't find a zinc located in the engine's cooling system than in my opinion you would be very wise in getting a top notch mechanic to do a electrolysis damage inspection or do it yourself if you are capable of it. If it's okay and there's no provision for a zinc you can install a inline zinc pencil holder in the cooling hose close to the engine and run a ground wire from the zinc holder ( terminal post ) to your common ground point in the boat.
The last address for Sendure I have is - Sendure Products Inc. 25 Moffitt Boulevard P.O. Box 110 Bayshore, N.Y. 11706 Ph: 516/665-0689
or branch office at 6785 N.W. 17th Ave. Gateway Industrial Park, Ft. Lauderdale,Fl. 33909 Ph: 305/973-1260. This info is dated so I'm not sure its accurate. I know Defender Industries carries their products. Their phone is 860/701-3424. I hope this helps you. Feel free to contact me for more info on the thirty.



Riesimage @ juno.com
Steve

Re: FRESH WATER MD7A

Post by Steve »

I have a CD30 with salt water cooled MD7A. I attach a 1" diameter zinc to the shaft about 6" fore the prop each spring. It's
about half dissolved when I pulled the boat in the fall. Isn't that sufficient to prevent electrolysis damage?

Steve A.
CD 30 Intrepid "Felicity"
Wickford, RI
John R. wrote:
Judy Clasen wrote: I'm a first time visitor to this Great web site. I'm seriously considering the purchase of a CD30 that has a raw water cooled Volvo MD7A (13hp). After mastering the servicing requirements of my Universal 14hp fresh water cooled diesel, I'm a little concerned about the reliability/problems associated with raw water cooled engines. Do most CD30's have Volvo's with raw water cooling? If anyone can help ease my doubts I would really appreciate it. Also if anyone in the Bay Area is interested in selling their CD30 (Alberg designed, cutter rigged) please contact me via email.

Thanks and Happy Sailing
We have a '83 30 foot cutter with a MD7A. I'm actually surprised to hear that some thirty footers were furnished as raw water cooled. Our
MD7A has fresh water cooling from the factory. It is comprised of a heat exchanger made by Sendure Products, a Jabsco pump mounted on a plate in front of the thermostat housing with a second belt running to the alternator, and a Sendure coolant resevoir / expansion tank mounted inside the starboard cockpit locker, a few extra hoses and thats it. I had a Island Trader ketch with a 30hp Yanmar that was raw water cooled and never had problems with cooling. I always kept an eye
on the engine zinc condition, and changed them when they were down to fifty percent of their original size. The MD7A doesn't have zincs in the block or cooling system that I'm aware of. The service manual also
does not show any in that engine. My Sendure heat exchanger has one in the bottom of it for the raw water side of the cooling system. I can't imagine any MD7A's that are raw water cooled without a zinc fitted somewhere in the cooling system, if not, it's a formula for destruction to that sweet little diesel. If the boat your looking at is raw cooled as you mention and you can't find a zinc located in the engine's cooling system than in my opinion you would be very wise in getting a top notch mechanic to do a electrolysis damage inspection or do it yourself if you are capable of it. If it's okay and there's no provision for a zinc you can install a inline zinc pencil holder in the cooling hose close to the engine and run a ground wire from the zinc holder ( terminal post ) to your common ground point in the boat.
The last address for Sendure I have is - Sendure Products Inc. 25 Moffitt Boulevard P.O. Box 110 Bayshore, N.Y. 11706 Ph: 516/665-0689
or branch office at 6785 N.W. 17th Ave. Gateway Industrial Park, Ft. Lauderdale,Fl. 33909 Ph: 305/973-1260. This info is dated so I'm not sure its accurate. I know Defender Industries carries their products. Their phone is 860/701-3424. I hope this helps you. Feel free to contact me for more info on the thirty.


srarnold@concentric.net
John

Re: FRESH WATER MD7A STEVE ARNOLD

Post by John »

Steve wrote:
I have a CD30 with salt water cooled MD7A. I attach a 1" diameter zinc to the shaft about 6" fore the prop each spring. It's
about half dissolved when I pulled the boat in the fall. Isn't that sufficient to prevent electrolysis damage?

Steve A.
CD 30 Intrepid "Felicity"
Wickford, RI

Steve Arnold, I tried sending you an e-mail to address listed in your
message regarding the zinc info you want. Your e-mail server returned
the mail each time. I tried several times.
Here's the scoop- you are protecting the underwater running gear and
not doing much if anything for the engine. You need a zinc in the raw
water cooling line directly, with the zinc connected to the common
ground point of the boat. As far as I know the MD7A has no zinc
provision directly in the block itself.
See other message or post good e-mail address for direct reply.
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