One engine covered in soot

[Nick_H]

Just did my engine checks before a long passage tomorrow, and my starboard engine has a thin but noticeable film of soot/oil over most of it, that wasn't there before today's 60 mile passage. There's also soot/oil on the inside of the hull under it. The port engine is still relatively clean and white.

Stbd engine runs fine, temps and pressures are normal, any ideas?

 

[aquapower]

Just did my engine checks before a long passage tomorrow, and my starboard engine has a thin but noticeable film of soot/oil over most of it, that wasn't there before today's 60 mile passage. There's also soot/oil on the inside of the hull under it. The port engine is still relatively clean and white.

Stbd engine runs fine, temps and pressures are normal, any ideas?

I would check exhaust for leaks.

 

[Nick_H]

Thanks. im struggling to decide whether to continue with a long passage tomorrow, 200 miles 10 hours. Is this the kind of issue that can deteriorate or cause secondary problems?

 

[aquapower]

Thanks. im struggling to decide whether to continue with a long passage tomorrow, 200 miles 10 hours. Is this the kind of issue that can deteriorate or cause secondary problems?

I think before a 200 mile passage I would like to know the problem first, if exhaust leak its most likely to get worse with time, exhaust leaks in engine room make a lot of mess that's difficult to clean up.

 

[aquatom]

Check exhaust elbow for cracks. If it comes off completely it will make a really bad mess.

 

[petem]

Soot or belt dust?

 

[Nick_H]

OK, thanks, I'll delay the trip and do some investigation.

 

[Nick_H]

Soot or belt dust?

I'm pretty sure it's not belt dust as it seems too evenly distributed over a large part of the engine, and more so at opposite end to the belts

 

[[2068]]

Check obvious things first, like the crankcase breather.
Then around the turbo, and the exhaust to the hull fitting.

 

[Nick_H]

Check obvious things first, like the crankcase breather.
Then around the turbo, and the exhaust to the hull fitting.

Crankcase breather filters are clean, and exhaust to hull fitting is remote from the engine room, but I'll check the turbo and exhausts in the morning

 

[Nick_H]

With cold engines this morning I've been able to have a closer look, and I may have been too quick to write off the crankcase breathers as the problem. This area does seem to be the epicentre. The filter elements look relatively clean, but the canisters were quite loose and I could tighten them up easily by hand. There is some oil around the base of the filter and on the underside of the manifold, but there is on the port engine as well, although those filters seem tight. The stbd filters are also rusty on the outward side, whereas the filters on the port engine look like new. Could this signify a bigger problem caused by heat? Both sides have been on for a year.



I can obviously replace the filters, clean up the mess, and go for a spin to see what happens, but I'm interested in views on whether there could be a bigger problem causing the filters to deteriorate and spray a film of oil around

 

[Momac]

Perhaps the engine has been overheating , but not so much as to sound an alarm? Check the raw water strainer and the impeller.

 

[spannerman]

If its soot then this will be leaking from the exhaust system somewhere, and while running the engine will be taking its air from the engine room, this results in it breathing in its own soot which can clog your air filter or if it goes further it can collect in the intercooler if you have one which will then need cleaning. Have experienced this on a couple of customers engines. You can sometimes detect exhaust leaks at engine start up when its smokes the most before all cylinders are running evenly, you need to be down by the engine with a torch if its dark and have someone start the engine, you will see a quick puff of black smoke when the engine first starts if its an obvious leak, I would be looking at the turbo outlet/bend as if its leaking down stream of the water injection point you would probably see some moisture leaking along with the exhaust gas.

 

[omega2]

Do not know your set up or the age of it but also look for aging and perishing of rubber exhaust hose and the clips that hold it onto the elbow.

 

[volvopaul]

Hi nick ,D 12 have elbow problems by corroding away , look under the jackets you will see they leak gas at the joints , I've replaced many .
Oil out the breathers is worrying as that means crank case blow by . Is the black on the engines a dry black film if so its soot , if it's wet black it's oil , usually the oil must out the breather is sucked into the air filters which in turn blocks them causing the engine to black smoke , if you have an exhaust leak it's a vicious circle . Email me a pic .

 

[Hurricane]

Hi nick ,D 12 have elbow problems by corroding away , look under the jackets you will see they leak gas at the joints , I've replaced many .
Oil out the breathers is worrying as that means crank case blow by . Is the black on the engines a dry black film if so its soot , if it's wet black it's oil , usually the oil must out the breather is sucked into the air filters which in turn blocks them causing the engine to black smoke , if you have an exhaust leak it's a vicious circle . Email me a pic .

Paul - our D12s on our old Sealine - the breathers used to "spit" oil but I switched from the Volvo oil to Rimula and then the breathers stayed nice and clean.
I assumed that the Volvo oil was foaming - at least more than the Rimula.

Also a friend with a T52 - I'm sure the exhaust bends that he had a problems on his D12s a couple of years ago. From memory, they sit at an angle where water can collect.
My friend was talking of replacing his with with stainless.

 

[Nick_H]

Good call VP, aqua power and others. The exhaust elbow from the turbo to the water injection elbow has corroded away next to the flange.

It looks quite an easy job to change it, is there anything I need to watch out for, or do I just unbolt the flanges at both ends, remove the old one, then bolt a new one in?

It seems the loose crankcase filters were a red herring

 

[jfm]

Hi Nick
I'm a bit unclear now whether this is oil film or soot. If soot then obv an exh leak, no big deal. My previous D12s had elbow failures but it tended to be the shiny Halyard part (injection elbow) not the upstream pre-water-injection parts, and so I tended to get water leaks from there not gas. But of course there are several joints and any could leak gas. You should see a "jet pattern" of soot under the jacket telling you where the leak is. The fix is exhaust paste and remake the joint

If it is oil film then it is likely coming from the crankcase filters and is caused by blowby as already said. However, I don't think this is bad on D12. My first D12s, which I had from new till 830 hours, had the same symptom after a season on the same filters. I think the oil mist inside the crankcase tended to block the filters after a while and the pores that were unblocked tended to "jet" the oil out. I therefore tended to get some claggy oil deposit on the filters (outer casing) yet the degree of engine blowby was nowhere serious at all and certainly not a case where you'd strip the engine. After I sold the boat the next 2 owners did another 800 hours without any problem. The boat is now in Turkey so I've lost touch. These were same series D12 as yours, 2003 build. So if I were you I'd just change the crankcase breather filters, and get into the habit of doing that every 75 hours, and see how you get on.

Can I help with sourcing them? I'm on Tuesday evening LHR-NCE and you have my Baldricks schedule

 

[jfm]

Good call VP, aqua power and others. The exhaust elbow from the turbo to the water injection elbow has corroded away next to the flange.

It looks quite an easy job to change it, is there anything I need to watch out for, or do I just unbolt the flanges at both ends, remove the old one, then bolt a new one in?

It seems the loose crankcase filters were a red herring

Ah good (we crossed posts). You just bolt the new one in, with exhaust paste. Make sure the hardened old paste bits don't drop back down the pipe to the turbo. Can wait till after holiday? Again, let me know if you need any transportation: I am BA front end next week so have 3x32kg allowance one of which you can have, and am checking stuff into the hold anyway

 

[Nick_H]

Thanks John. We've booked into Bormes les Mimosas, so the plan is to go to the VP dealer when they open after lunch to see if they have one, or if I can get a taxi to somewhere that does, maybe Toulon

If I can't get hold of one today, I may try a temporary repair bandage for the weekend. I think the hole is too big to just run it anyway, as it's about 2" long x 1/2" wide

Thanks for the offer re luggage. I'm guessing I can get one locally though, and at current fx rates it may even be cheaper!