Slight smokiness from engine bay.

[Guest]

Hello again you helpful bunch. So the purchase of my boat is complete! YAY.

 

Now that bit of excitement is out of the way... I have a slight issue now I have started moving my new home back to its mooring spot. There seems to be a small amount of smoke coming from the engine bay up though the electrical cupboard door. I noticed a tiny amount whilst cruising on the first day but thought nothing of it. Then I stuck my head in the cupboard while the engine was running and there's definately smoke or fumes of some sort there.

 

I ran the engine from cold out of gear for a few minutes the following day and there's no smoke to begin with, but it begins to drift up after maybe 5 minutes. Its not billowing out by any means, and it's only very thin smoke, I would probably have to say 'dark grey' if a colour is at all helpful.

 

When the survey was done and the engine was run under load for about an hour I didn't notice any smoke at all and neither did the surveyor.

 

Is it possible I've been the complete novice and not done something I should have before starting off? Seeing as the boat may have been sitting idle at the brokers since the survey about a month ago, would there be anything you can think of that might be causing this?

 

Any advice would be greatly appreciated before I resort to calling someone to take a look at it before setting off again.it is a Beta Marine 35 hp... Apologies,I don't know the exact model as I'm not back with the boat until tomorrow, but it's green if that's any use.

 

I shall prepare my embarrassed face for when the solution may turn out to be one of obviousness.

[Guest]

I doubt you have missed something that would cause it.

 

Have you checked for any leaks in the exhaust? between the engine and the outlet in the hull.

 

The smallest crack or hole would cause fumes to leak into the engine bay and beyond.

[bizzard]

Possible rain trickled through the floor boards onto exhaust lagging and or oilyness steaming off the lagging, especially if its a cruiser stern.

[Rickent]

Does sound like an exhaust leak, is it unusually loud ?

[ditchcrawler]

Breather pipe putting fumes into the boat

[Guest]

Thanks for your lightning responses.

It's a trad stern, so not sure if any rainwater has managed to get down there. I had a quick look into the engine bay and couldn't quite figure out where the smoke was coming from. The engine doesn't seem particularly loud, not to my ear anyway. As far as I can tell it sounds the same as when I had it run at the viewing and survey.

 

I will have a proper check of the exhaust when I go back tomorrow and see if I can spot anything.

[Chalky]

Other things to look for. Some engines have ventilated breather/ oil filler caps. Have a look and see if the vapour is coming from there. Also does the smoke have a smell to it? Does anything feel hot (be careful with this just in case). If its in the vicinity of the electrical cupboard are any of the cables rubbing on anything?

[Guest]

The smoke does have a smell yes, I will take a whiff and try and get back to you with a detailed description of what vegetable/animal/beauty product it resembles.

 

Obviously without knowing exactly what it is this question may be hard to answer, but would you all advise getting this fixed before moving any further?

[Neil Smith]

Could be a slight oil leak that will smoke when engine gets hot.

 

Neil

[jonesthenuke]

Trad stern so what sort of engine? does it have a breather and is it smoking?

[Guest]

I won't be able to look again until tomorrow so I'm not sure of the exact engine, I just know it's a green Beta 35hp. I'm not sure if it has a breather (I'll also have to find out where I can find this before I can see if it's smoking) but I'll check all these things and see what I can come up with.

[Sea Dog]

I won't be able to look again until tomorrow so I'm not sure of the exact engine, I just know it's a green Beta 35hp. I'm not sure if it has a breather (I'll also have to find out where I can find this before I can see if it's smoking) but I'll check all these things and see what I can come up with.

Have a look at the Beta Marine website - they publish all their engine manuals and diagrams in pdf format for free download.

 

It's impossible to say whether it's essential that it's fixed before you move on until you know the source really. It could be as simple as oil spilled when topping up burning off when the engine gets hot which will disappear quite quickly and have few consequences, it could be a friction issue perhaps ultimately resulting in a snapped belt, it could be an electrical problem which could cause a fire, or it could be a myriad of things between. Those issues would smell oily, rubbery and 'electrical' though, so trust your nose. Mainly though I just wanted to tell you about the manuals rather than speculate. Good luck!

[Bee]

Most likely reason is what others have said, nothing much to worry about. Only the mention of electrics is a worry, you do need to make sure this is not something electrical and if it is then get it fixed as these electrical things can be a risk.

[pophops]

If you suspect an exhaust leak look carefully at the exhaust lagging. The area of the leak should begin to show signs of sootiness or blackening of the lagging. The slightest pinhole or crack in the exhaust will cause fumes to escape.

[Chalky]

If it smells sweet then it could be coolant. If it is keep an eye on it and fix it soon. There are various consequences from coolant leaks ranging from head gasket failure through to fire - the antifreeze is highly flamable.

[MtB]

Tricky.

 

The source of smoke can be fiendishly difficult to find in the windy environment of the engine bay with the engine running.

 

My best advice is to call the surveyor and ask his opinion, given he had a good look over the boat recently.

[cuthound]

Has somebody recently topped up or changed the engine oil and spilt some?

 

I had that with a car once.

[Tony Brooks]

If it smells sweet then it could be coolant. If it is keep an eye on it and fix it soon. There are various consequences from coolant leaks ranging from head gasket failure through to fire - the antifreeze is highly flamable.

 

!!!!!! Source for that please. It decades since methanol based antifreezes were readily available for cooling systems.

[Guest]

Thanks again for all the tips. I've spoken to the surveyor and he too thinks it may be exhaust related. Im not sure when the oil was topped up or by whom but I couldn't see any obvious spills. I'm heading to le boat today so I shall post my findings tonight.

[Chalky]

 

!!!!!! Source for that please. It decades since methanol based antifreezes were readily available for cooling systems.

 

It's not the methanol, its the ethylene / propylene glycol that ignites. Mixed with water it's not an issue until it gets hot enough to boil off the water. At that point the glycol ignites.

 

I've included a couple of references from a number of sources including a published conference paper.

 

http://www.croberts.com/coolant.htm

 

Conference paper - International Symposium on Fire Investigation Science and Technology 2008

http://www.reifire.net/text/ethylene.pdf

 

http://www.nfpa.org/safety-information/for-consumers/fire-and-safety-equipment/home-fire-sprinklers/current-requirements-for-sprinkler-systems-containing-antifreeze

Edited May 11, 2016 by Chalky

[bizzard]

Engine antifreeze leaks that bake on a hot engine smell like curry. When I used to open the bonnet of any vehicle and instantly smelt curry I knew there was a leak somewhere on the engine.no matter how small.

[Tony Brooks]

 

It's not the methanol, its the ethylene / propylene glycol that ignites. Mixed with water it's not an issue until it gets hot enough to boil off the water. At that point the glycol ignites.

 

I've included a couple of references from a number of sources including a published conference paper.

 

http://www.croberts.com/coolant.htm

 

Conference paper - International Symposium on Fire Investigation Science and Technology 2008

http://www.reifire.net/text/ethylene.pdf

 

http://www.nfpa.org/safety-information/for-consumers/fire-and-safety-equipment/home-fire-sprinklers/current-requirements-for-sprinkler-systems-containing-antifreeze

 

Well that gives a flash point of around 250C and a self ignition temperature of 750C. so I do not see that as being, I quote, "Highly inflammable" .

 

On that score diesel is much more readily ignitable and I think few of us would consider that as highly inflammable.

 

Combustible I would agree with so I will let others decide the suitability of the highly inflammable tag.

[Chalky]

 

Well that gives a flash point of around 250C and a self ignition temperature of 750C. so I do not see that as being, I quote, "Highly inflammable" .

 

On that score diesel is much more readily ignitable and I think few of us would consider that as highly inflammable.

 

Combustible I would agree with so I will let others decide the suitability of the highly inflammable tag.

 

The temperatures are in farenheit, not celcius

 

250 F = 121 C

750 F = 398C

Edited May 11, 2016 by Chalky

[Tony Brooks]

 

The temperatures are in farenheit, not celcius

 

250 F = 121 C

750 F = 398C

 

Still higher than diesel then.

[MtB]

Engine antifreeze leaks that bake on a hot engine smell like curry. When I used to open the bonnet of any vehicle and instantly smelt curry I knew there was a leak somewhere on the engine.no matter how small.

 

 

Either that or you knew it was a curry delivery van....