Volvo MD 11C

"I own a Centaur yacht fitted

"I own a Centaur yacht fitted with a Volvo MD 11C fresh water cooled engine. The heat exchanger is cooled by raw water. I am baffled as there is no anode within the cooling system. As the heat exchanger contains different metals i/e lead solder, copper etc how are Volvo able to dispense with an anode in this instance when it is deemed necessary in other marine engines?????
Thanks - John."

"The MD11C is a pretty old eng

"The MD11C is a pretty old engine and dates from a time when sacrificial anodes were not always/often fitted in engines. The MD11 does not even have an anode in its cooling system when directly sea water cooled!

Maybe Volvo Penta felt that the combination of metals in the heat exchanger did not need an anode. What metals are present and in contact? Is it assembled using an ordinary tin/lead solder?

Your heat exchanger is presumably a good few years old now so what parts of it are being affected by galvanic corrosion?

Generally anodes are often fitted in situations when they are not needed. It has become a fashion to fit hull anodes, shaft anodes etc as a precautionary measure and because people expect to see them. If your Centaur has any anodes they were almost certainly not original standard equipment and if the boat still has the original propeller probably not necessary.

BTW check the YBW forums at www.ybw.com/forums"

I have remover the Gearbox fro

I have remover the Gearbox from the back of my MD17C and there is oil in the bell housing on the engine is this normal? If so is ther a gasket between the engine block and the Bell housing as we have had oil in the bilges

"Brendan, If you find out the

"Brendan, If you find out the answer to your question, I'd like to know as well. I have two MD11C engines, one a replacement used engine from a friend who says he thinks it is leaking a bit of oil from a rear oil seal; the other engine is one with a spun bearing I just removed from my boat. I am currently in the process of tearing apart the one from the boat - rebuilding will be a big job, I may not even complete. But I plan to at least explore the rear area of the crankcase to see how I would go about stopping oil leakage in the other engine. I have to be careful because I'm not a pro mechanic and I don't want to tear down any part of the replacement engine that I can't get back together with the right tolerances, without special tools, etc.
If I find anything of interest, I'll let you know!
Dennis"