Diesel fumes

Nov 28, 2013
19
Hunter 36 36 Hampton
I recently purchased a 1998 Hunter 340 with a yanmar diesel. On our first overnight adventure we motored for about 4 hours after the wind died. When we went below what I believe was diesel exhaust fumes were unbearable. The smell was in all ours cloths, towels and cushions. We had put about 15 hours on the boat in the last month and up until this trip hadn't noticed any problem. Any suggestions?

Thanks in advance
Walt Bailey
 

Johnb

.
Jan 22, 2008
1,462
Hunter 37-cutter Richmond CA
1 If you don't have a carbon monoxide detector get one yesterday. Better still get two.

2 My wife and I recently chartered a Morgan Out Islander which has portlights in the stern. On one of the days we motored with them open. The aft cabin filled with diesel fumes. Had one of our grandkids been napping in there we may have killed it.

3 When a piece of the mixing elbow fell out whilst motoring the carbon monoxide and fire alarms both went off at just about the same time.

4 Hopefully what you smelled was just an accumulation of dust and oil that got boiled off and is not actually an exhaust leak. That would be true if you do have a CO detector and it is working.

5 Sorry to come on so strong but this is a critical matter.
 
Jan 4, 2006
7,297
Hunter 310 West Vancouver, B.C.
When we went below what I believe was diesel exhaust fumes were unbearabley
Everything that Johnb has listed plus ...........

- open every port and hatch in the boat

-remove the engine cover and have someone above start the engine

- VERY carefully run your hand over all exhaust fittings ahead of the sea water injection. If the leak was after, you'd definitely know where it was.

- if that doesn't work, wait for someone to post a plan B here.
 
Nov 6, 2006
10,104
Hunter 34 Mandeville Louisiana
If you aren't sure it is exhaust, check all the fuel lines and fittings for any dripping or weeping while running.. including the fuel return hose going from top of injectors back to the tank.
also, Check the top connections on the water lift muffler.. make sure all hose clamps are tight on the large diameter exhaust hoses.. Check to make sure that the breather hose on the valve cover is connected to the intake manifold.
 
Feb 6, 2009
257
Hunter 40 Camano Island
Check for exhaust leaks as you would for a tire leak

dish soap, water and either a spray bottle or small bristle paint brush.

with the engine cold, spray/brush the solution of warm soapy water over the exhaust components. turn the cold engine on.

leaks are easy to spot., popping bubbles and quickly drying areas
 
Nov 28, 2013
19
Hunter 36 36 Hampton
Thanks everyone for the advice, located the problem and installed Co detectors
 
Oct 29, 2005
2,362
Hunter Marine 326 303 Singapore
Thanks everyone for the advice, located the problem and installed Co detectors
Walter, I guess you've beaten Alfred Hitchcock in the suspense stories.... Soooo where was the problem?? :doh: :confused: