No power / black soot! -spoilt run out

[mjf]

Well finally ventured out on saturday as at least not raining; even the f4/f5 would prevent play this w/e.

Got into open water, power up and thought I was towing a 20 tonne boat behind me.

max rpm 2000 and boat would not plane. Funny I thought as she came out in March and had stern gear polished etc and the boat was tremenous last time out (6 weeks ago!). Tried again and just managed to get 11knots which increased to 14 passing Cowes. (This is a 30knot craft remember). Got the turbos to cut in just! which allowed her to climb onto the step.

Finally after managing to get to anchor in IOW I saw that the back of the boat was covered in soot (never seen this before!) - it was like a coal face.

I did about 20miles all told with the throttles wide open I would achieve 2000rpm max - I was able to throttle back 2/3 on the sticks without any loss of speed or revs so I lost the last 30% revs which is where the power is.

Same problems on return trip yesterday....... There is a multitude of young barnicles on the water line antifouling which did not appear in the past 16 months on the Solent.


I have spoken since to another MOB owner who keeps his boat at the same marina and he could not get on the plane at all so turned around and went home in tears.....


Question - is this a growth on the shafts / problem or what?


I would have been more concerned if both engines had not suffered identical power issues and the fact that another guys has similar problems with a near identical in water time since haul out / hair cut and shave......

Opinions welcome - why the soot?


Michael

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[Talbot]

get some soltron, and change your filters - sounds like dirty diesel.

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[KevB]

Lots of problems with growth on boats at the moment, I know of at least three boats who have had the same problem. Would almost gaurantee it's dirty props/bottom/shafts causing it. As for the soot I guess it's cause you are over fueling with the throttles full on but only doing 2000 revs.



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[longjohnsilver]

Get it scrubbed/cleaned, paying particular attention to the props and shafts. I would expect that to completely solve your problem.

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[amf]

Not in Port Solent are you?

Our boat wasn't used for 3 weeks. Planned to go to Dartmouth last weekend. Could only do 2500 revs at WOT (should be 3800) - had to turn around and drive down. Thought it was a reoccurrence of a turbo problem but boat was lifted and drive/props covered in barnacles which we had scraped off. Went out this weekend and was able to get up to 3600 revs so still down 200 revs but much better than it was.

Volvo dealer said they have had a week of people reporting vibration/lack of revs problems with their boats in PS. Seems to be much worse this year.

Doesn't explain your soot problem though.

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[mjf]

The fuel in the glass looks / is clean -no water etc. Is there somewhere else to look?

To answer amf , yes Puerto Solento.


I cannot believe this effect can occur over 6 weeks.......


Michael

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[longjohnsilver]

6 weeks

It can and does most certainly happen in such a short time, all the little blighters were no doubt there last time the boat was used but have now grown, and boy do they grow fast!

I regularly clean my hull and props, but in 4 weeks there was sufficient growth on the prop to give both a reduction in speed and vibration! Once cleaned all back to normal.

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[amf]

I didn\'t believe it either but...

...we went from clean to covered in 3 weeks (or from 28 kts to 9 kts).

I do think there is a particular problem in PS - maybe caused by the stillness of the water behind a lock?? - Any marine biologists out there?

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[mjf]

Re: I didn\'t believe it either but...

Christ!

I had better get scuba gear back in service and work out a way to power (air?)polish the bronze bits. What is the disadvantage of antifouling these bits with todays super techo paint systems?

I had 6 smallish barnicle jobs on the shafts when she was hauled in March 04 after 12 months in the marina and lots of use over the summer/autumn/ winter etc. I was amazed at the clean condition of both the hull and unpainted bits.

What is so different this year?


I wonder if that 'solent bloom' that was discussed in april/may was the little sods in micro form?



Michael

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[Chris_B4]

I was in the water in the middle of June and cleaned the drives as best I could, many young barnacles which I could just about remove with my fingers. I didn't use the boat for three weeks and then realised I would have to have it lifted to get rid of the massive infestation of barnacles that had subsequently grown on my drives.

Couldn't believe what I found when lifted, little sods were even living on the inside of the props in the exhaust flow.

Didn't have this probem last year and from what others are saying it seems boats in Port Solent have particluarly suffered.

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[Bergman]

Perhaps asylum seeking barnacles imported on the bottom of a boat from the south of France after levering off the copper cladding

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[mjf]

Thanks


I am now told that lots and lots of people had this trouble last w/e.

The soot is because the engine draws too much fuel which is not correctly burnt and the over-rich condition causes the soot.

Sounds feasable to me - will know after the lift out and paint / polish next week.


Michael

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