That Smell . . .

[DevaDeb]

I am new to the cruising world but I'm trying to give it my best shot...that diesel smell really makes me sick. What to do? Isn't there some means for making it less obtrusive? Or, will I get used to i?

[Bash]

due to their heightened anxiety, new sailors tend to be far more prone to seasickness than seasoned pros. the more prone you are to seasickness, the more likely that you'll be annoyed by diesel fumes.

it will never smell pleasant, but there's a good chance that someday you'll find it less obnoxious.

[marshmat]

If you can smell it at offensive levels, something's not right. The only point at which diesel fuel vapours should be finding their way out of the system is the fuel tank vent, which exits overboard. I start to suspect a leak whenever I smell fuel anywhere other than that vent (or, in the case of older gas engines, the carb intake).

Of course, it's also possible that you just have some fuel odour left from a long-ago spill, exacerbated by bad ventilation. Fresh air (lots of it, preferably moving, getting into every nook and cranny) is the best solution I know of....

[Bash]

marshmat and I seem to be addressing two different phenomena. One is the smell of the exhaust from a running diesel engine. The other is the smell of the raw fuel itself.

Which smell is the problem here?

[Intentional Drifter]

I agree with Matt. We have 2 diesels in our cat, mounted midships and the only time we ever smell diesel is right after I've changed out the fuel filters and that doesn't last long. (for the life of me, I just can't seem to do that job without spilling at least a little bit and that's all it takes to make a stink)

I think you've got a leak somewhere. Like I said, it doesn't take much. So little in fact that it might never actually accumulate enough to notice it pooling.

I'd trace every inch of your fuel system from tank to cylinder head and back again on the return line. Wrapping every connection point with a strip of dry paper towel will help to locate a drip.

It might be a lot of work, but think how relieved you will be when you find it and get it fixed! It'll make all the difference in the world to you.

ID

[Mi2ndWind]

I had a similar issue early this season, on the first run across the bay to the marina, then on the "shake down cruise". The odor of what smelled like unburnt diesel was very obtrusive inside the boat. I wanted to run it a bit before doing the first oil change of the season, which turned out to be a mistake. Opening the engine bay door revealed what at first looked like exhaust smoke, but was actually caused by incorrect oil (non-detergent 10w-30) used by the P.O. to winterize the engine. The oil smoke was so bad (in the engine bay only, not the exhaust) that the breather became plugged in very short order. An oil change with correct high detergent straight 30 oil and a thorough cleaning of the breather solved the problem. If you can't find any fuel leaks, check and clean the breather and make sure the blower (if you have one) is working. Good luck!

[Rou-Coo]

Originally Posted by Bash

it will never smell pleasant, but there's a good chance that someday you'll find it less obnoxious.

Au contraire! I worked commercial tugs and the like when I was a young man and I still love the whiff of diesel exhaust. Nothing like it to bring back the deep seated memory of standing on the afterdeck cruising up the channel.

While it may be a fuel leak the OP is talking about I suspect it is just a bit of exhaust exaggerated by the 'fear factor'.

[maxingout]

I don't mind the smell of diesel fuel, but the diesel exhaust really bothers me. The smell of diesel exhaust can be hard to escape in certain wind conditions and sea state. The main reason I don't like motoring is because of the smell of diesel exhaust.

[Bash]

Originally Posted by Rou-Coo

Au contraire! I worked commercial tugs and the like when I was a young man and I still love the whiff of diesel exhaust. Nothing like it to bring back the deep seated memory of standing on the afterdeck cruising up the channel.

I suspect your situation might be considered a special case. Especially given that most tugboats, ever since the days of coal-fired steam tugs, have been burning bunker fuel.

Which also stinks, in my opinion.

[zeehag]

dont listen to when they say you will get used to it--lol--NOT--but DO listen to how they made it less obnoxious--thare are ways to make the smell less bad--i use fan to blow toward the engine room and out---helps. opening ports and hatches helps. being outside in the air helps...my formosa doesnot smell when idle. neither does my ericson. if it does--there is something can be done about it, depending what is not working correctly.--

[Dockhead]

Originally Posted by Rou-Coo

Au contraire! I worked commercial tugs and the like when I was a young man and I still love the whiff of diesel exhaust. Nothing like it to bring back the deep seated memory of standing on the afterdeck cruising up the channel.

While it may be a fuel leak the OP is talking about I suspect it is just a bit of exhaust exaggerated by the 'fear factor'.

Ah, the smell of napalm in the morning!

Like you, I get a strong shiver of delight whenever I smell diesel exhaust, or for that matter, two-stroke exhaust, as the result of a deep-seated psychological association with getting out on the water.

[MarkJ]

Matts advice is good.
Check for leaks or faulty venting.
We never get any smell on here.

If your boat is older and has deep bilges maybe some special attention to spills that previous owners have not cleaned up properly.
I hate to mention any of those overly expensive bilge cleaning products in the chandelry, but maybe good hot water and detergent scrubbing of the sides of the fuel tank, all the bilges, especially where you can't see or reach, and all the yucky places.

Obviously do your checking for leaks first. And check the vent is clear too.

Now we get into areas I don't know about but I'm just thinking....: if there has been fuel in the bilges and its mixed with other liquids and slopped around it may have produced some mold or bacteria thats paining your nose.

If its the oily smell of the engine when its running and your head is in the engine bay then thats a 'normal' smell and as Dockhead says: "[I love], the smell of napalm in the morning!" It smells like.... victory! Its your smell of freedom

[pete33458]

I love the smell of diesel fuel in the morning. Smells like.....victory.

[DevaDeb]

Thanks all for the replies and helpful info. As you might have guessed, I am not only new to cruising but also to forums such as this...I should have clarified up front, this is a newly purchased boat is on the hard being fixed up after several years of disuse. Thus, the smell is from diesel fuel, a possible leak that has not yet been identified, combined with a lack of fresh air.

A few of you also validated claims from my spouse that it is that obtrusive "fear factor"...I'm working on that one!

[Bash]

okay. that makes it easy.

the two things that are intolerable on a sailboat are:
1. leaks;
2. poor ventilation.

make certain your tank vent is working adequately, while you're dealing with ventilation.