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post #10 of Old 01-11-2008
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I recently purchased a 1991 43' moderately heavy sailboat in Annapolis after I received a glowing survey, successful sea trial and reassurances from the owner and broker that everything was in great shape. I signed the papers, then had the fuel polished, and had a diesel mechanic change filters, and do baseline service. When he started the engine, his face went blank.
The engine was loping at low speeds, and had had a unsteady sound. He unloaded the fuel injectors by cracking the connection one at a time, and found the #2 cylinder dead.

did it sound like this during the sea trial.

The local Yanmar dealer did a compression check, changed the injectors, and still no #2. He looked into the cylinder with a boroscope, and found "sodium deposits" from seawater in the cylinder. The most likely source was seawater siphoning back into the engine likely because of a bad antisiphon valve. After removing the head, and measuring the cylinders and spotting extensive corrosion, he concluded that the engine needed extensive overhaul,

that may not have happened during the short time between seatrial and diesel guy... "extensive" is a relative term, but to me, sounds like a longer period of exposure than what is being said.

and it may be more cost effective to replace the engine. In any event, the engine will have to come out of the boat. Fortunately, the existing exhaust has 3" pipes, required for the new Yanmar. Ironically, the boat has never left the slip since I owned it, (only a couple of weeks)

just the oil and carbon buildup of normal operation wouldn't allow such "extensive" damage.

I am planning on replacing the Yanmar 4JH2E (1991 54 HP with 3000hr) with a new Yanmar 4JH4TE (75HP and only slightly more expensive). The gearing will be optimized for use with my existing Autoprop.

let me see if I have this straight, you're "optimizing" the engine and tranny to match an existing prop... 9-12k, vs 1500 for a different prop?

Does anyone have experience with a bad survey, and engine flaws from the previous owner (who must have known if he did the service he claimed)? Are there any big penalties going to a more powerful engine (turbo with same block size)?[/I]

Usually, there is O&E insurance (omissions and errors) but I'm not sure this would be applicable. I wouldn't have done a compression check either. If the engine sounded like it was having a problem during the seatrial, I'd have heard it. So would the surveyor (assuming... i know, i know) FOLKS THIS IS WHY YOU GET A DAMN OIL SAMPLE!!!!! A perfect time for one would have been at the completion of the sea trial. This would have given you an idea about when, where, why and who regarding the condition of the motor AT THAT MOMENT OF TIME.

Did the diesel guy start it before the repair? (if he was doing an oil change, he should have.
Did anyone take the boat out after the seatrial?

what to do now.
a) whoa there big fella.. Get a second opinion as to if the motor can be repaired. And what the failure was, and what it is caused by.
b) Start gathering records, oil changes, maintence, find out who did what, when, ask the mechanics about the motor and boat.
c) Heres my take on turbos's. They have no place on a sailboat. they run at higher rpms, hotter temps, neither good for the engine room of a sailboat.

We are not primarily on earth to see through one another, but to see one another through

Some people are like slinkies: not really good for anything... but you can't help laughing when you push them down the stairs
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