Thick black smoke

[Bewildered]

I have noticed that my exhaust has started issuing billowing clouds of thick black smoke on high engine revs (1500 or so Rpm) this suggests poor air/fuel mix probably from blocked injectors.

I know nothing about injector systems so will need to seek out professional help, so what I would like to know is how in-depth a job it is so I can get an idea of what a job like this should cost. Is it for example as simple an hour to remove an hour to clean and an hour to replace, in which case I would expect an estimate for half a days labour? Or is it going to be a lot more complicated?

we are currently on the Leicester branch just above Crick and heading south towards Leighton Buzzard, there are plenty of marinas and small boat yards on this route, which one would be the best bet for this type of work?  Will probably get a full service at the same time, is it feasible that all work would be done in a single day?
 

Lister 4 cylinder replaced with an industrial block and with the top end from my original canal star. Thought I best add that bit before all the questions start ?

 

[Tracy D'arth]

14 minutes ago, Bewildered said:

I have noticed that my exhaust has started issuing billowing clouds of thick black smoke on high engine revs (1500 or so Rpm) this suggests poor air/fuel mix probably from blocked injectors.

I know nothing about injector systems so will need to seek out professional help, so what I would like to know is how in-depth a job it is so I can get an idea of what a job like this should cost. Is it for example as simple an hour to remove an hour to clean and an hour to replace, in which case I would expect an estimate for half a days labour? Or is it going to be a lot more complicated?

we are currently on the Leicester branch just above Crick and heading south towards Leighton Buzzard, there are plenty of marinas and small boat yards on this route, which one would be the best bet for this type of work?  Will probably get a full service at the same time, is it feasible that all work would be done in a single day?
 

Lister 4 cylinder replaced with an industrial block and with the top end from my original canal star. Thought I best add that bit before all the questions start ?

 

Clean air filter?  Prop fouled overloading the engine? Silencer coked up?  Its not just cleaning injectors; they need the break off pressure setting. That is why you will need a diesel repair shop where they have all the equipment.

They are easy to remove but on the Lister LPWs you need a set of the special rubber seals to replace them.

[dmr]

Have you totally eliminated the obvious, badly clogged air filter or something round the prop?

 

...............Dave

[Tony Brooks]

Or have you been sound proofing and made the engine bay airtight

[Higgs]

 

Sounds as though the fuel is getting into the cylinders, just not burning completely. ?? My BMC normally runs clean, but I had to really throttle it hard once, to avoid a collision, the exhaust was black. 

 

 

 

Edited September 26, 2020 by Higgs

[Bewildered]

30 minutes ago, Tracy D'arth said:

Clean air filter?  Prop fouled overloading the engine? Silencer coked up?  Its not just cleaning injectors; they need the break off pressure setting. That is why you will need a diesel repair shop where they have all the equipment.

They are easy to remove but on the Lister LPWs you need a set of the special rubber seals to replace them.

New air filter around 6 weeks ago, will check it later anyway. Don’t think the prop is fouled but will take a look. No idea how to check if the silencer is coked up without removing the exhaust. I suspect that all bolts are going to be so tight they are more likely to break than undo. I’m not a mechanic so yes I probably Bly need a specialist.

 

8 minutes ago, Tony Brooks said:

Or have you been sound proofing and made the engine bay airtight

No soundproofing did replace the steel deck boards for buffalo board last year but I suspect there is more airflow now than before.

Just now, Higgs said:

 

Sounds as though the fuel is getting into the cylinders, just not burning completely. ?? My BMC normally runs clean, but I had to really throttle it hard once to avoid a collision, the exhaust was black. 

 

 

 

That’s how I noticed it, having to give it full reverse for the boat hiding in a bridge hole 

[Higgs]

2 minutes ago, Bewildered said:

That’s how I noticed it, having to give it full reverse for the boat hiding in a bridge hole 

 

Almost exactly what happened to me.

 

 

[Bewildered]

1 minute ago, Higgs said:

 

Almost exactly what happened to me.

 

 

So it’s you that lurks in bridge holes then?

[Higgs]

2 minutes ago, Bewildered said:

So it’s you that lurks in bridge holes then?

 

Are you the much heavier work boat, whose driver was tucked in a cabin, had no chance of hearing my horn? 

 

 

[Bewildered]

10 minutes ago, Higgs said:

 

Are you the much heavier work boat, whose driver was tucked in a cabin, had no chance of hearing my horn? 

 

 

Not me, honestly guv. 
driver tucked in a cabin whilst negotiating a bridge hole, that is cocky driving 

[David Mack]

21 minutes ago, Bewildered said:

Don’t think the prop is fouled but will take a look.

 

For Gawd's sake check the easy stuff first before you start taking anything apart.

 

The chap in the thread below didn't and is now rather red-faced!

 

[Higgs]

47 minutes ago, Bewildered said:

Not me, honestly guv. 
driver tucked in a cabin whilst negotiating a bridge hole, that is cocky driving 

 

It was a BW work boat, with an enclosed cabin as standard, though, I never heard his horn being used. 

 

 

 

Edited September 26, 2020 by Higgs

[Tony Brooks]

1 hour ago, Bewildered said:

New air filter around 6 weeks ago, will check it later anyway. Don’t think the prop is fouled but will take a look. No idea how to check if the silencer is coked up without removing the exhaust. I suspect that all bolts are going to be so tight they are more likely to break than undo. I’m not a mechanic so yes I probably Bly need a specialist.

 

No soundproofing did replace the steel deck boards for buffalo board last year but I suspect there is more airflow now than before.

That’s how I noticed it, having to give it full reverse for the boat hiding in a bridge hole 

 

If you gave it far more welly than usual it may just have been a bit of overloading. Nothing to worry about but perhaps an indication the prop may be a bit oversize.

[David Mack]

1 hour ago, Bewildered said:

That’s how I noticed it, having to give it full reverse for the boat hiding in a bridge hole 

 

Exactly the sort of situation where you are likely to pick up a bladeful of crap!

[Tracy D'arth]

54 minutes ago, Tony Brooks said:

 

If you gave it far more welly than usual it may just have been a bit of overloading. Nothing to worry about but perhaps an indication the prop may be a bit oversize.

Most older diesel engines will chuck clinkers and smoke from the exhaust if revved suddenly and hard.  The silencer will be packed with carbon after slow running for hours. The sudden injection of fuel in excess of what the engine revs can cope with produces particulates. That's why an MOT on your diesel car includes a full throttle emission test, the particulate level must fall after the initial acceleration to pass the test.

[Bewildered]

2 hours ago, Tracy D'arth said:

Most older diesel engines will chuck clinkers and smoke from the exhaust if revved suddenly and hard.  The silencer will be packed with carbon after slow running for hours. The sudden injection of fuel in excess of what the engine revs can cope with produces particulates. That's why an MOT on your diesel car includes a full throttle emission test, the particulate level must fall after the initial acceleration to pass the test.

As this is a 20 year old boat and I suspect it is the original exhaust system it is most likely well choked up. Perhaps it is time to get a nice new hospital silencer fitted

[Tracy D'arth]

46 minutes ago, Bewildered said:

As this is a 20 year old boat and I suspect it is the original exhaust system it is most likely well choked up. Perhaps it is time to get a nice new hospital silencer fitted

Well worth it for the peace and quiet.   Trouble is you then spend all day listening to the noises that you never heard before!

[beerbeerbeerbeerbeer]

Every now and again I give my engine a good hard rev to clear it. 
Black smoke for a few moment then clean. 
 

 

[Higgs]

4 hours ago, Tracy D'arth said:

Most older diesel engines will chuck clinkers and smoke from the exhaust if revved suddenly and hard.  The silencer will be packed with carbon after slow running for hours. The sudden injection of fuel in excess of what the engine revs can cope with produces particulates. That's why an MOT on your diesel car includes a full throttle emission test, the particulate level must fall after the initial acceleration to pass the test.

 

I don't know what the MoT station did to my car during the test, but it ran like crap for weeks and I noticed a difference immediately. 

 

 

[Keeping Up]

1 hour ago, Goliath said:

Every now and again I give my engine a good hard rev to clear it. 
Black smoke for a few moment then clean. 
 

 

Commonly known as an "Italian tune-up"