Pair of very smokey AD41's.....

[dpb]

The boat, which belongs to a freind, is a 30ft flybridge (gibsea gibralter) on shafts, about 1990.
Upto 1800rpm all fairly normal.
The videos show what happens from 1800rpm to about 2900rpm.
Temps and oil pressure about right.
Turbos can be finger turned.
Injectors have been serviced and intercoolers checked.
I am thinking turbos are the problem.
The bottom is dirty for sure, 2 years since scrub, but is that capable of causing this?
Not sure if clear in vids but what looks like globules of black oil emitted in with the smoke.
Anyone had similar and found solution.
Thanks

 

[QBhoy]

That looks like carbon deposits getting burned off or displaced.

 

[dpb]

That looks like carbon deposits getting burned off or displaced.

Ok, but cause and cure?

 

[stelican]

Are you getting on the plane?

 

[38mess]

An Italian tune up might help

 

[vas]

clean the hull before destroying the engines, doubt it planes as stelican points above!

 

[Montemar]

Clean the hull then decide what the problem is. Cheaper than new turbos!

 

[Plum]

The bottom is dirty for sure, 2 years since scrub, but is that capable of causing this?

Yes. Highly probable.

 

[dpb]

No it does not quite get on the plane.
There is growth but could it cause smoke that bad?

 

[vas]

No it does not quite get on the plane.
There is growth but could it cause smoke that bad?

YES!

 

[Seastoke]

Common denominator , as both engines are doing it , the only other thing is fuel.

 

[Mr Googler]

YES!

Where’s Porto and EGT’s when you need him

 

[Mr Googler]

Common denominator , as both engines are doing it , the only other thing is fuel.

Ermmmmm…..black smoke is over fueling.…not under

 

[Portofino]

Where’s Porto and EGT’s when you need him

Just catching up .Yup the fouled hull is the culprit.
If you had EGT deltas or load …….It’s mega overloaded .

Continued usage like this will as Vas said destroy the engines , the excessive heat burns the injector tips = hose = melt pistons .

 

[Seastoke]

Ermmmmm…..black smoke is over fueling.…not under

I was saying , if both are doing it , only two things affect both water and fuel. But I bow to you sir.

 

[dpb]

Ok. Thanks all.
Cleaning the bottom before anything else makes good sence to me.
Will report back in due course.

 

[NBs]

Hi,

maybe the green transition is a good thing!

The smoke is as if the boat is heavily over propped, so bottom maintenance could really be the reason.

There may be other reasons, but turn over this card first.

NBs

 

[colhel]

If it's on shafts wouldn't it be tamd41 engines? I had a problem with black smoke which was cured with a bottom scrub but I'm sure it wasn't as bad as that. Just another thought, is max revs at WOT being achieved (3900?), are the props correct? Are the trim tabs stuck?

 

[Portofino]

Does it smoke in N at the dock ? …..I mean over 3 k rpm when warm .

 

[dpb]

Wot is 2900 at the moment.
Props assumed original.
Trim tabs work ok and dont make much difference.
Have not tried reving over 3000rpm in dock.
My friend is arranging for boat to be lifted.
Will update this post with progress.