Ask Professor Diesel

Onan genset spewing black smoke

By | Posted December 2010

Question: I have a 4-kW Marine Onan genset with 600 hours on it. If I let it run for a lengthy period it produces so much black smoke that a residue discolors the hull around the...

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Noisy Engines

By | Posted November 2010

Question: I have a pair of Detroit Diesel 6-71 TIBs in my 1990 Ocean 48 Super Sport. I love both the boat and the motors, but the Detroits have always been loud at the exhaust end...

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Twin Engine Temperature Disparity

By | Posted October 2010

Question: I have a 1994 Mainship 31 with a pair of 315-hp Yanmar diesels with 2,000 hours on them. While running at full throttle (about 33 knots) for five minutes, the starboard...

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Algae On My Racor

By | Posted September 2010

Question: While performing routine maintenance on my Caterpillar C7, I was surprised to find a substance about the size of a quarter at the top of my Racor—it looked like...

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Professor Diesel

By | Posted November 2009

Q. I have a 2003 Sea Ray Sundancer 420 and am moving from the New York City area to Florida soon. Do I need to do anything different in Florida in terms of boat maintenance? I am...

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Getting your engine ready for launch in the spring

By | Posted February 2009

Question: I’ve always wondered if there was anything special I should do when getting my boat ready for launch in the spring. My mechanic says no, just start her up,...

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