Diesel Fumes & Ventilation

[raycoker]

I have a 1987 303. Yanmar 16. I get a lot of diesel fume smell below when under power. The engine room is sealed well. I also noticed that I do not have any ventilation anywhere on the stern. It seems to me that I should mount an intake and exhaust vents on the stern and attach an inline fan to the exhaust with the hose down near the motor.

When I get back to the slip I always have to let it air out.

I am a novice and just got this pearson. I had the engine checked out by mech before purchase. It runs cool and well.

Please advise.

 

[weinie]

Check your exhaust connections. I had the same problem this week and found a leaky seal and a cracked intake on my muffler. New muffler coming today!
Put your hands near the hose connections and exhaust manifold when the engine is running. You should be able to feel air coming out if there is a leak. If your elbow is has a crack some where, you may be able to see black soot around the exhaust tape. (or so my mechanic said).

 

[raycoker]

Thanks Weinie

I will check that.

 

[Stu Jackson]

1. Diesel engine need two things to run: fuel and AIR. A sealed engine compartment is not so good.

2. In addition to the other ideas, check all exhaust connections, and also check the exhaust hose itself. We just replaced our 26 year old 17 foot long exhaust hose, which had been leaking all along its length due to its age.

3. It's unclear from your post if it is exhaust smell or diesel fumes. If the latter, too, check the fuel hoses for age and leaks, as well as the tank.

 

[SVCarolena]

We have an 84 P303 with a Yanmar 2GM. When we got the boat, we found that the exhaust elbow had rusted through in a small spot. The previous owner tried to seal the opening with a fiberglass patch. That didn't work and exhaust was leaking into the engine compartment. Yanmar considers the elbow to be a wear item, so you may want to start there. As for ventilation, if you look at the cockpit locker cover it should have plenty of ventilation around it. Provided yours is like ours and no one has installed seals . . . I also wondered about ventilation when we got the boat, until I discovered that the locker is designed to allow for plenty of ventilation.

 

[weinie]

I just installed my new muffler today and although I definitely got rid of the leaks that I had, the engine compartment still filled up with fumes!

After poking around I realized it was coming from the crankcase breather tube. Although the end of the tube was right near the air intake, it wasn't sucking enough in. I simply put the end of the tube directly into the intake and... voila, problem solved!

 

[shipwreck66]

I always turn on my exhaust fan before starting engine and run it for a couple minutes after shutdown. The fan was really intended for the older gasoline Atomic 4s for exhaust, but does a really good job of venting a lot of the engine smell out the port vent. The admiral hates engine smells and this has helped quite a bit.

 

[raycoker]

Thanks, same problem and leak in an injector that I had to really look for to find.

 

[raycoker]

Thanks, it was both. Leak from injector and all hoses need to be tightened.

 

[raycoker]

Good point. Turned out to be a leak...no smell now.