Very strong gas fumes , boat dies after 45 mins

corona2627

Seaman Apprentice
Joined
Jun 19, 2010
Messages
41
Just finished a two year rennovation of my 1971 glastron v-174 Mercruiser 165 inline 6. Has most everything new except gas tank, gas line, engine and exhaust. Sterndrive was in good condition. Took it out today for the first time. Ran great for the first 45 mins, but very strong gas fumes coming from the bow of the boat where the gas tank is located. Boat stopped dead in the water. Thinking it was not getting gas, I change in small carb filter and took the Racor water seperater off and just hooked the gas line into the pump. After about 20 mins, started and ran for abt. 15 more mins then stopped. Had to be towed in...Any suggestions would be most appreciated.


Dianne
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Very strong gas fumes , boat dies after 45 mins

Cracked fuel hose, possibly near the tank, allowing fuel out (hence the smell) and air in (hence the lack of engine noise)....

Chris......
 

corona2627

Seaman Apprentice
Joined
Jun 19, 2010
Messages
41
Re: Very strong gas fumes , boat dies after 45 mins

I checked for any gas, none was apparent, crawled down and felt around top of tank where line was, could there be something else, could the vent maybe be clogged, would that cause strong fumes and gas starvation?
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Very strong gas fumes , boat dies after 45 mins

If the vent was clogged, then you would not get any fumes... It takes very little petrol to make a whole lot of smell. I would remove the supply line from the engine, plug the vent line and use a SMALL amount of compressed air to try and see where the leak is. Soapy water and a small paint brush works really well... Or pressurise the vent line and plug the engine supply line... Your choice, whatever is easier... But if you do go climbing into an enclosed space, have someone else there to drag you out when you lose consciousness... :D

Chris.....
 

corona2627

Seaman Apprentice
Joined
Jun 19, 2010
Messages
41
Re: Very strong gas fumes , boat dies after 45 mins

If I didnt lose consciousness yesterday, I never will....Thanks so much, I will look for a leak...
 

ziggy

Admiral
Joined
Jun 30, 2004
Messages
7,473
Re: Very strong gas fumes , boat dies after 45 mins

everything new except gas tank, gas line,
why'd ya stop there at not replacing the fuel line? imho, i would find it hard to believe that the rubber fuel line hasn't degraded since 1971. on my '75 boat i just replaced the fuel line between the fuel tank on general principles. i want my fuel line to be in as good of shape as it can be. fuel vapors and boats don't go together very well. imho. replace the fuel line. if that don't cure the leak, yer gonna have to go find it. imho it's imperative that you find this leak so you don't run the risk of explosion of your boat.
 

corona2627

Seaman Apprentice
Joined
Jun 19, 2010
Messages
41
Re: Very strong gas fumes , boat dies after 45 mins

Thanks Ziggy, believe it or not it still has the copper fuel line in her....taking her today to she her machanic that last worked on her.....getting to old to crawl around in tight spaces, and had enough of gas fumes for a while. Your right, gas fumes are nothing to fool around with and since Im a trauma nurse by trade and a shade tree machinic on my down time, I'd rather not be a trauma patient. I think I will let someone trained to do this one....thanks everyone, you guys have helped me all through my rennovation, and I much appreciate all of your expert advice.

Dianne
 
Top