Black soot from Exhaust

[lcochrane]

I have a 10 year old Volvo 2030 on a 34.2' Jeanneau SO.
When I am motoring and increase rpm above around 2600, black soot appears in the exhaust water.
It stops as soon as I drop below 2500rpm

Is this cause for concern?

 

[robmcg]

Over propped, fouled hull, fouled prop, blocked air filter - will likely be one of these.

 

[PetiteFleur]

Check the exhaust water injection elbow - you'll have to remove the elbow completely to check properly - mine only had a 10mm hole down the centre! A new elbow cured all problems.

 

[tillergirl]

Check the exhaust water injection elbow - you'll have to remove the elbow completely to check properly - mine only had a 10mm hole down the centre! A new elbow cured all problems.

I agree, ditto with me. The exhaust elbow is really a service item. I got 15 years out of mine before it went like PetitFleur's.

 

[Stork_III]

I have a 10 year old Volvo 2030 on a 34.2' Jeanneau SO.
When I am motoring and increase rpm above around 2600, black soot appears in the exhaust water.
It stops as soon as I drop below 2500rpm

Is this cause for concern?

If soot present when revved in neutral, 100% blocked exhaust elbow.

 

[lcochrane]

Thanks for the replies
All very helpful

 

[sailorman]

Thanks for the replies
All very helpful

what is the engine `s rated RPM

 

[tillergirl]

what is the engine `s rated RPM

3600 I think

 

[sailorman]

so 2600 is well under

 

[Stork_III]

so 2600 is well under

OP doesn't say 2600 is max revs, that soot starts above that level.

 

[NormanS]

Check the exhaust water injection elbow - you'll have to remove the elbow completely to check properly - mine only had a 10mm hole down the centre! A new elbow cured all problems.

Was the 10mm hole in the water elbow, or the actual exhaust elbow? The reason for asking is that on investigation, I found that although my exhaust elbow was clear, the water elbow which is flange jointed onto the exhaust elbow, was reduced to even less than that.
The fact that it fell apart in my hands, is another story. Mine, of course may be entirely different as my engine is an MD22.

 

[sailorman]

OP doesn't say 2600 is max revs, that soot starts above that level.

True ( i was in Addenbrookes for 4 wasted hrs this arvo :sleeping & didnt read it correctly