Volvo Penta D4 260 twin with dph - black smoke on one engine / low boost pressure

[papparazzi]

Hi all,

my boat runs 2 x Volvo Penta D4-260 with DPH sterndrives. The engines are from 2010 with EVC-D and have around 640 hours on it. Both turbos seized this summer (rusted on exhaust side) and had been replaced 6 months ago. Whilst they was seized, no black smoke developed but engine wouldn't get on full RPMs and has less power (e.g. only some 2500 rpm).

Yesterday the boat has been taken out after 2 weeks again and whilst pushing on plane I inspected the turbo pressures (this boat has compressors as well) and saw that port was significantly lower followed by port being only at some 2200 rpm whilst starboard was going towards 3000 already and the port engine was blowing a lot of black smoke behind us.

As I never had the engines blowing black smoke I was alerted and went in idle right away, opened the engine bay to check for any issues and luckily there was nothing obvious (also no smoke in engine room). I continued a short ride of 2nm on low RPMs of 1500 - 2000 without problems.

The boat has been newly anti fouled some 2 months ago and the bottom is pretty clean. Props are having some barnacles but not to dramatic and nothing more then we had it in the past. Both engines run of the same diesel tank which likely rules out fuel quality issues. The air / oil filters have been changed 1 year ago (max 40h) alongside the primary diesel filter. The secondary diesel filter (at the d4 engine) are 2 years old, we couldn't get the water sensor off them last time and therefore reused them as not to break the sensor and being grounded until we get a new sensor.

My questions are:
- what could be the problem ?
- could a faulty boost/temp sensor result in EVC / ECU providing to much diesel
- could a dirty (airside) aftercooler result in the black smoke ?
- if the injectors would be dirty, wouldn't the black smoke also be at lower rpms (below 2000) ?

How critical is the black smoke - would it be acceptable to drive with the black smoke for some miles / minutes to see if it goes away once the boat get's on plane or once the engine gets on higher RPM ?

Thanks !

 

[oldgit]

Totally anecdotal comment..............FWIW.
Chum had Fairline Brava with the earlier generation of 6 cylinder engines with supercharger and turbo charger combination.
Lying idle on the Thames for quite some time.
Bringing it home , was decided to try and go to WOT, the first time very little happened apart from clouds of smoke.
On the second attempt the boat was very gently eased up to WOT ....Loads of black smoke for a few minutes and then it gradually cleared.
Achieved max revs, all T&Ps on the button and around 23 knots.

 

[papparazzi]

Totally anecdotal comment..............FWIW.
Chum had Fairline Brava with the earlier generation of 6 cylinder engines with supercharger and turbo charger combination.
Lying idle on the Thames for quite some time.
Bringing it home , was decided to try and go to WOT, the first time very little happened apart from clouds of smoke.
On the second attempt the boat was very gently eased up to WOT ....Loads of black smoke for a few minutes and then it gradually cleared.
Achieved max revs, all T&Ps on the button and around 23 knots.

Thanks. How was the next ride with the boat - still black smoke ? Was it because the boat hasen't been used for a longer time?

 

[oldgit]

Thanks. How was the next ride with the boat - still black smoke ? Was it because the boat hasen't been used for a longer time?

Boat was on trip from the Thames to the Medway on a Bray Marina Club cruise.
The boat was previously used as a pied-à-terre in Limehouse marina for quite some time before being used at only 6 knots above the lock at Teddington.
All fuel filters had been changed in prepartion for the trip back round to the Medway.
Performed perfectly on the return trip.

 

[volvopaul]

Replied to your post on Facebook

 

[papparazzi]

Replied to your post on Facebook

Thanks @volvopaul . If I understand it correct you would suspect the propeller hub on the starboard engine to be spun which would explain it to rev up higher whilst the port engine would have black smoke due to overload. I had a few weeks back a ride at 28 knots / 3100+ rpm and whilst pushing it towards WOT the engines both intermittently lost power and I went in idle. On the next attempt to get on plane the it felt as when the props would be slipping, RPMs shoot up but not in line with the forward propulsion. I drove the remaining part on low speed at around 1500 rpm and inspected the situation a few days later and all was 'gone' and back to normal. This was after a DPH service with new oil and shaft seals so that time I was worried there might be some other problem. Whilst I never found out what it was, I was driving a few hours now without these issues including 80%+ of the WOT.

Question: If I would have a spun propeller hub (these are the G4 / H4 props) would this even be possible that sometimes all is good and another time it would slip? Shouldn't it slip all the time above a certain % of load / or force ? (typically latest when we try to get on plane)?

One other question I have in mind - D4s are fully electronically managed engines (electronic injection) - I don't quite understand how they would be injecting more fuel as needed given they should have a air mass / air volume sensor? Back when I had the suspected spun hub I tried each engine alone in WOT and observed both turbos near full boost but the rpms couldn't get much beyond 2500 or similar. I would imagine that single engine at WOT was at overload but yet I didn't get black smoke.

The black smoke I got the other day was not just some smoke in the water / wave - it was like a smoke wall behind the boat

I am starting to think I might have some electronic issues / connection issues with the ECU / EVC-D (which we plugged out some 3 months back when changing the turbos).

I will investigate:
- Exhaust side of turbo --> turbine free or not (I pray no issue as they turbos are only 6 months old)
- swap the MEP (mass / air temp) sensor from port to starboard (I read many folks have issues with these)
- check air filter +flap (door) in the air box

How would I check the spun hub?

 

[papparazzi]

Question - I read that fouled propellers could result in black smoke - propellers had been polished 3 monhts ago but buy now have developed some fouling but in my mind nothing to bad. However, any experience on this? Both would be fould equally so not sure that's really it.

 

[papparazzi]

Hi all, check air filter today and flap in air filter box - both don't seem to be the problem. Air filter is somewhat dirty, will be replaced as annual service comes up now but there is no emgine oil in filter nor in air filter box.

However, my primary filters had up to 50% of the bowl filled with water and diesel bug was smimming on top of it. They had been changed 1 year / 40h ago. Secondary engine filters haven't been changed 1year ago and are therefore coming to 2 years but below 100h. Racon 500 uses 10 micron filters of which the bottom 30% was blackish

I now suspect the earlier mentioned fuel starvation due to diesel bug in primary and possible secondary filters. I will change and clean the filters and hope that's the solution. Any thoughts of this could have been the black smoke issue at higher engine load? Low engine load I don't got black smoke.

 

[oldgit]

Question - I read that fouled propellers could result in black smoke - propellers had been polished 3 monhts ago but buy now have developed some fouling but in my mind nothing to bad. However, any experience on this? Both would be fould equally so not sure that's really it.

Princess 410.
Unable to go more than 8/10 knots and clouds of black smoke.
Blades smothered in barnecules but hull clean, diver called in to scrape them off and all OK afterwards.
Both propellers had amazing amount of growth on them, boat not used for 6 months.
Would have thought that light coating of prop surfaces not the problem and the fuel system more likely to be the cause .

Change all filters and do seem to recall a little mesh screen inside the lift pump ?

 

[papparazzi]

I changed and cleaned the diesel filterd today and checked for the compressor boost without sterndrive being engaged (100% throttle position).

Stangly my port engine (which had black smoke) only has 30 kph whereas starboard hs 70 kph. Not sure how that's related, eventually the turbo is stuck and reduce the compressor flow rate as both make the same amount of noise whilst engage.