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Good morning everyone - I hope someone can point me in the right direction.

 

We've got a Dutch steel cruiser with an almost new (70 hours) Vetus VH4.65. Some time ago we picked up a sleeping bag on the prop - so lots of black smoke as we limped home (we couldn't stop for a while as we were on the Trent.) Unfortunately, at the same time, the exhaust riser worked its way free and therefore a lot of this black smoke was released into the engiine bay (and so sucked in by the engine). Anyway, we got the sleeping bag removed, and everything seemed fine at first.

 

However, the engine is now very smoky (white smoke) after 30 minutes or so under load. It's not at all smoky when running out of gear - even at moderately high revs and for long periods of time. The fuel is clean and free of water. Air intake is fine.

 

Any thoughts? I'm not sure the bit of history in para 2 is relevant, but seems to me it might be.

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This shows the potential issues of just keeping going. I realise stopping could have been difficult on the river.

 

The "smoke" may be unburnt fuel but it could also be steam from a broken head gasket letting in water from the cooling system to the combustion chambers. The fact that it comes after 30 minutes running could mean it is steam. The "limping home" could have over heated the engine. The engine needs to be looked at ASAP. It's not going to get better by itself.

Edited by churchward
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If its a river water cooled engine I'd check the mud box/weed filter. I get steam out of the exhaust sometimes if the water intake mud box is blocked

Steam can Appear to be white smoke - last time it happened to mW I was concerned it was dirty diesel but it turned out I had not resecured the lid of the mud box properly and it was letting air in so the cooling was compromised.

Edited by magnetman
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This shows the potential issues of just keeping going. I realise stopping could have been difficult on the river.

 

The "smoke" may be unburnt fuel but it could also be steam from a broken head gasket letting in water from the cooling system to the combustion chambers. The fact that it comes after 30 minutes running could mean it is steam. The "limping home" could have over heated the engine. The engine needs to be looked at ASAP. It's not going to get better by itself.

Thanks for that. There's certainly been some loss of coolant - would that be part of it? Would symptoms be different under load and not under load, though?

If you have had an exhaust leak, check your air filter

 

Richard

Checked, thanks.

If its a river water cooled engine I'd check the mud box/weed filter. I get steam out of the exhaust sometimes if the water intake mud box is blocked

Steam can Appear to be white smoke - last time it happened to mW I was concerned it was dirty diesel but it turned out I had not resecured the lid of the mud box properly and it was letting air in so the cooling was compromised.

Thanks - checked that last weekend.

Edited by bozlite
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Good morning everyone - I hope someone can point me in the right direction.

 

We've got a Dutch steel cruiser with an almost new (70 hours) Vetus VH4.65. Some time ago we picked up a sleeping bag on the prop - so lots of black smoke as we limped home (we couldn't stop for a while as we were on the Trent.) Unfortunately, at the same time, the exhaust riser worked its way free and therefore a lot of this black smoke was released into the engiine bay (and so sucked in by the engine). Anyway, we got the sleeping bag removed, and everything seemed fine at first.

 

However, the engine is now very smoky (white smoke) after 30 minutes or so under load. It's not at all smoky when running out of gear - even at moderately high revs and for long periods of time. The fuel is clean and free of water. Air intake is fine.

 

Any thoughts? I'm not sure the bit of history in para 2 is relevant, but seems to me it might be.

 

Thanks for that. There's certainly been some loss of coolant - would that be part of it? Would symptoms be different under load and not under load, though?

 

I'm not familiar with this particular engine model, but the white smoke after a spell under load and the coolant loss are typically symptomatic of a leaking intercooler matrix on a turbocharged engine.

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I'm not familiar with this particular engine model, but the white smoke after a spell under load and the coolant loss are typically symptomatic of a leaking intercooler matrix on a turbocharged engine.

Thanks, Tony - no turbocharger on this engine, though.

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I realise that its 'stable door time' as far as you are concerned, but maybe as a suggestions for others in the same situation.

 

At the 1st sign of any abnormalities, (engine revs changing or 'hunting', smoke, vibration, unusual rattles, temperature rising, gearbox problems) drop anchor (that's what you carry it for), remove offending article / repair problem, start engine, retrieve anchor and carry on.

Don't wait until you get to a nice place to stop - it could be too late then.

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I realise that its 'stable door time' as far as you are concerned, but maybe as a suggestions for others in the same situation.

 

At the 1st sign of any abnormalities, (engine revs changing or 'hunting', smoke, vibration, unusual rattles, temperature rising, gearbox problems) drop anchor (that's what you carry it for), remove offending article / repair problem, start engine, retrieve anchor and carry on.

Don't wait until you get to a nice place to stop - it could be too late then.

Sound advice - but with something round the prop, on a river, and with no weedhatch, options seemed rather limited. Happy to don my drysuit and leap into a canal, but not a river. Could've tried to arrange a tow, I suppose.

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Thanks for that. There's certainly been some loss of coolant - would that be part of it? Would symptoms be different under load and not under load, though?

Checked, thanks.

Thanks - checked that last weekend.

Yes the loss of coolant is consistent with a blown head gasket as that will be where the water is coming from into the combustion chambers and creating steam. A compression test may help prove the problem as there is likely to be a drop of compression on a cylinder or two but possibly not much as it sounds like the engine is starting and running reasonably. A change of head gasket is probably not that expensive to do particularly if you do it yourself.

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Thanks, Tony - no turbocharger on this engine, though.

 

I can't remember the model or type, but I can recall, on an occasion when attending to some sterngear problems on a Vetus engined boat, noticing that the inlet manifold had been incorporated into the heat exchanger/exhaust manifold casting.

This is a little unusual, but probably done that way on that particular engine because of cylinder head design and port positioning considerations.

If your engine has a similar heat exchanger body/casting, then a defect or crack in the casting could possibly allow coolant to seep into the inlet combustion air flow as temperature and cooling system pressure rises with the engine under load.

You could commence checking for and eliminating this possibility by running the engine up to the load/temperature conditions when the white smoke has been appearing, but with the H/ex'er pressure cap left loose.

Edited by Tony Dunkley
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Yes the loss of coolant is consistent with a blown head gasket as that will be where the water is coming from into the combustion chambers and creating steam. A compression test may help prove the problem as there is likely to be a drop of compression on a cylinder or two but possibly not much as it sounds like the engine is starting and running reasonably. A change of head gasket is probably not that expensive to do particularly if you do it yourself.

The Vetus part will be eye-wateringly expensive, though! Perhaps I can source an alternative - it's just a Hyundai van engine after all. Anyway, not a job I'm capable of myself - anyone know a good diesel mechanic near Nottingham?

 

Thanks again, Churchward.

Edited by bozlite
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I can't remember the model or type, but I can recall, on an occasion when attending to some sterngear problems on a Vetus engined boat, noticing that the inlet manifold had been incorporated into the heat exchanger/exhaust manifold casting.

This is a little unusual, but probably done that way on that particular engine because of cylinder head design and port positioning considerations.

If your engine has a similar heat exchanger body/casting, then a defect or crack in the casting could possibly allow coolant to seep into the inlet combustion air flow as temperature and cooling system pressure rises with the engine under load.

You could commence checking for and eliminating this possibility by running the engine up to the load/temperature conditions when the white smoke has been appearing, but with the H/ex'er pressure cap left loose.

Thanks, Tony. If I understand you correctly, the engine is as you describe: 1adc11cbb7aaf7dabcd1b1fadaf68d7d_zpsis72

The test you suggest is helpful, too.

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Thanks, Tony. If I understand you correctly, the engine is as you describe: 1adc11cbb7aaf7dabcd1b1fadaf68d7d_zpsis72

The test you suggest is helpful, too.

 

The test described, on it's own, will narrow the problem down to being either water leakage into to inlet combustion air flow, or a head gasket leaking between a water passage and a cylinder wall, so the best way forward with this is to carry out the under load [with the cap loose] running test and a combustion gas leakage test at the same time.

The results from the combined test will indicate whether it's head/head gasket or a leaking [ into the inlet ports] heat exchanger casting.

 

Before getting even this relatively simple and inexpensive test done, it would be well worth you running it up under load to smoking temperature with the cap off and watching for any sign of air bubbles forming and surfacing under and around the filler neck on the H'ex'er, or combined manifolds/header tank if it's keel cooled. If it's head or head gasket there will be a distinct smell, similar to diesel exhaust fumes, coming out of the filler neck whilst the engine is running.

 

If your engine is identical to the one in the photo's you've posted, and particularly if it's keel cooled, it would be well worth checking for water leaks from the rubber piping on the engine oil cooler, . . . . the air intake is just above, and very close, and there could be something as simple as a pin hole leak spraying water at it.

Edited by Tony Dunkley
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. . . . . . . . . . . . . . . - anyone know a good diesel mechanic near Nottingham?

.

 

Yes, . . . . . I know a very good one. You can get him on 07553 294325.

Edited by Tony Dunkley
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The Vetus part will be eye-wateringly expensive, though! Perhaps I can source an alternative - it's just a Hyundai van engine after all. Anyway, not a job I'm capable of myself - anyone know a good diesel mechanic near Nottingham?

 

Thanks again, Churchward.

Yes that is true I forgot you said it was a Vetus engine their parts can be pricey. As you say though a gasket from another source is likely to be cheaper and Vetus will not have changed the basic engine components.

 

Tony Dunkley makes a good point too if that is the engines config and it is another way of getting water into the combustion chambers. So, worth testing for.

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