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Discussion Starter #1
Hi everyone.

While i have been fixing up my Jeanneau Poker, i have been using the engine as my generator to run the power tools and other things.

When i initially got the boat a couple of months ago, it was (still is) in a pretty rough shape. The engine filters haven't been changed, belts needed replacement and some hoses leaking. The engine was running fine though.

So i did a small service, changed the filters, added an air filter, changed the oil and in general cleaned it up a bit.

The problem started though a couple of weeks ago. The engine while was starting before from firts try and right away, now needs few cranks to get going. Also dies few times before revs up.

The Exhaust now gives lots and lots of black smoke, which is lowered when the engine heats up but never goes completely away.

The throttle takes almost 10 seconds to begin revving after i actually pull the throttle lever.

Could someone tell me what is happening and what could be the cause for all this?
 

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Dirt Free
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Does not sound good but always try the simple things first , remove the air filter you fitted, If it is non-OE it may be choking the engine. If that does not work it could be rings or injectors or injection pump ..... ouch !
 

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Over-fueling is the primary cause of black smoke from the exhaust of a heavy duty diesel engine. Over-fueling can be caused by diesel fuel injector wear that enlarges the nozzle hole or erodes the injector needle and allows excess fuel to flow into the combustion chamber.
I think you probably had an injector fail. Not the cheapest fix, but at least its not a lot of work to pull and replace injectors. Pull them all and send them to a shop that specializes in them. Ask a big rig repair shop for the name of a shop and stay away from the 'marine' scene and save some money.
 

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Discussion Starter #4
Tnx guys. Will check all possibilities. Hopefully i can have it back and running soon. My suspicion is the air filter though as it started once i installed it on.
 

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It sounds like you have been running the engine at low load for extensive periods. Diesels don't like that. If you don't have power where you are working on the boat, better to get a small portable generator.

One thing to check is the exhaust elbow. Your extended period of low power running may have plugged it up with carbon deposits.
 

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Discussion Starter #6
I removed the air filter and not much changed. I did find a used pump and injector but before i go ahead and bu those, could all this be caused by too much oil?

I did pour more than needed and i can see oil patches (not as much oil as stains filling up around the boat) when i try to start it.

Could the throttle slow response (almost non existent at the beginning) and the smoke be cause by too much oil? All this started after i serviced the engine.
 

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Discussion Starter #7
Well, i removed almost a liter of oil from the engine as it seems i overdid it.

The smoke is very minimal now and only at the start when it is cold. It does take few more cranks to get it going but when it does the throttle response is fine now. I filled the tank with some injector cleaner to clean the internals a bit.

I remember that the engine was starting before from first try with very little effort before. Not sure why it isn't now but i did notice that the Return line which is coming from the fuel filter was going into the tank into a port which didn't have a hole. Perhaps the pressure was building up and was starting faster. Fixed it now so the excess fuel leaks back into the tank as it should.

Ordered also a spare fuel pump and injector just in case.
 

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And be very careful about running the engine as a generator (risk of carbon monoxide). There have been a number of cases in the UK where there have been deaths caused on boats by CO poisoning whilst the engine has been running, but the boat stationary, but battery -charging, etc. (Google "MAIB" (Marine Accident Investigation Branch) and "Vasquez", or "Love for Linda" for 2 most recent cases, but there have been others).
Andrew
 

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1) Diesels thrive on hard, constant work that keeps them up to working temperature for most of the time. What they don't like is frequent start-stops, brief periods of operation, rarely reaching design operating temperature, living in a cold, moist atmosphere and infrequent oil changes.
2) Black smoke from exhaust Cause is incomplete fuel combustion. Can be due to injector problems, high load, poor compression and valve wear.
3) A further cause, when black smoke is accompanied by a severe reduction in maximum revs, is blockage of the exhaust manifold/exhaust risers by salts and or carbon build up.
4) Over filling any engine (especially diesels) with oil is dangerous, The normal oil level should only be between the low and full marl (Never Over)

Steve
 

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Discussion Starter #10
Well it wasn't any of those issues but something more drastic.

The one valve was sticking as a result of bad cylinder head gasket. The valve froze, bent the pushrod and the engine stalled.

The people at TW Marine were kind enough to send me a refurbished valve head, new valves, the gasket kit and i also replaced the water pump seals as that may also caused the water to come in. Changed the piston rings just in case, cleaned the whole thing and put it together.

Rebuilt the engine in a day and it purrs like a kitten now.

Also installed a Vetus Exhaust system so the water goes into the box and doesn't just sit inbetween the engine and the outlet. Hopefully this will be the last of my problems as the engine runs like new now. Almost am afraid to have it running now :)
 

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Well it wasn't any of those issues but something more drastic.

The one valve was sticking as a result of bad cylinder head gasket. The valve froze, bent the pushrod and the engine stalled.....:)
Good on you for sorting this out, thanks for the follow-up! ;)
 

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My first impression of your symptoms was injecter pump timing. I was thinking you might have a worn out timing chain. When they jump a tooth you loose power and acceleration is slow with lots of black smoke. Generally if and when it jumps another tooth the Pistons will contact the valves bending them or breaking the valve causing severe engine damage. A slack timing chain can be checked by pulling an injector and rotating the crank until the piston is at top dead center, insert a small plastic stir straw into the injector hole to see when the piston moves up and down. Rotate the crank left and right and you will be able to feel the slack in the chain. 6-8 degrees is about the limit of rotation you should see. Over that I would replace the chain and gears. The other, absolute method is to remove the timing chain cover and check to see if the marks are aligned property as well as the injector pump gear.
The second thing to consider is an injector stuck open. This will cause a slow throttle response, lots of black smoke. This condition with also burn and melt the top of the piston, a hydrolock may occur and blow a head gasket, break piston rings and bend piston rods and valves. Glad you got it worked out. If none of the above is the case you should be able to drive it like you stole it. Good luck.
 
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