Volvo engine experts help.

[mldpt]

Hi here we go again, my 2003 V/P has now been rebuilt, 4000 hours on the clock, Original problem, poor starting and excessive smoke, Had injectors serviced £180 cured the smoking but still poor starting, had head off exhaust valves badly burnt and seats pitted, had valves and seats re cut and lapped in, compression much better, and starts a bit easier, but now excessive unburnt fuel from exhaust. Had engine out bores honed new set of rings and bigend shells, old ones worn through to copper. I have been told that this is due to fuel getting past rings and into oil. its now rebuilt and has done 30 hours approx. She starts instantly, has loads more power, and revs to 2800 rpm which it never did before in 10 years, sounds wonderful, infact I am very pleased with it except for the smoke from the exhaust, at first I though it might need bedding in and I convinced myself it was getting better, but it is now leaving a far worse oily mess on the transom than before, I am sure it is unburnt fuel, as there is black sooty deposit in the water, could it be the Injectors if not what else could it be. The engine does'nt seem to use any oil now its bedded in. I will have the injectors checked again next week but has anybody any ideas.
Mike www.sailiingforfun.co.uk

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[Birdseye]

sounds like unburnt diesel. given that you have done the injectors, have you checked the air intake? is the filter clagged up? if not, then its back to the injectors etc

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[mldpt]

Hi thanks for you reply, I hav'nt checked the air filter but it was washed out not long before the work began in Jan however I will have a look and make sure, but would I still get the responsive power I now get, with the exception of the smoke she preforms better than at any time in the last 4000 hours. Mike

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[johnsomerhausen]

About that difficult starting, have you ever taken the starter motor to be cleaned and rebuilt ? I did so on my MD7A two years ago and the electrician said it was "full of gunk", which explained my starting problems.
john

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[TheBoatman]

Is the smoke coming all the time or just at throttle-up.
Have you checked that the props the right size and that the engine isn't working to hard at various throttle settings? This would give you black smoke!

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[mldpt]

Hi, The smoke is there all the time although not so notisable when underway as the transome digs in and the exhaust is then under water, I have had this boat and engine for 10 years and had the same prop so I am sure that is not the problem, but another post suggested that the problem may be a blocked Exhaust pipe, and as I did have problems with the exhaust elbow and the old pipe melted its possible that before I cured the overheating the same may have happened to the new pipe, I finally cured the heating problem by cleaning the water passages in the elbow, I now have a temp guage on the elbow, cost £10 from car shop a simple one with one remote senser which I have stuck to the side of the elbow and run the wire and digital readout back up to the instrument panel, so I can now watch the temp of the exhaust and if it rises above 40f then I have aproblem, rather than waiting for the engine to overheat and the alarm goes off, by then the damage to the pipe is done.
Mike www.sailiingforfun.co.uk

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[kgi]

What happened with my ovlov was after using oil for a while the INTAKE PASSAGE became restricted and left oily deposits and unburnt fuel just like you described, dropped the exhaust valves, got in there with a screwdriver, and removed about half a cup of solidified oil, god the intake was HUGE when i finished, after that engine fired up within a couple of turns, more revs, less smoke, for a while i would never have believed it was a volvo............keith

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