Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Mercury 60 EFI FUEL ISSUE

Posted by Jomanchu on 06/04/14 - 6:04 PM
#1

I have run out of ideas. I have a 2005 Mercury 60ELPTEFI. I noticed last year before I winterized it there appeared to be a little bit of fuel in water. Very minor. I prepared the boat to put in this year and now the fuel has some force and is not dripping but a steady stream from hole on bottom of engine. It is coming from the Vapor Separator Tank (VST). I have replaced the float and the float valve needle inside of the VST. Still flowing. The motor runs great other than that issue. Does anyone have any advice or suggestions? A new VST is 800 and I am not sure that will repair it. Thanks. Joe

Posted by tedious on 06/06/14 - 2:12 AM
#2

Jomanchu wrote:
I have run out of ideas. I have a 2005 Mercury 60ELPTEFI. I noticed last year before I winterized it there appeared to be a little bit of fuel in water. Very minor. I prepared the boat to put in this year and now the fuel has some force and is not dripping but a steady stream from hole on bottom of engine. It is coming from the Vapor Separator Tank (VST). I have replaced the float and the float valve needle inside of the VST. Still flowing. The motor runs great other than that issue. Does anyone have any advice or suggestions? A new VST is 800 and I am not sure that will repair it. Thanks. Joe


Joe, I am not familiar with this motor, but you'll need to clarify your description in order for people to even give you ideas:

- where did you see the fuel in the water before you winterised?
- what do you mean by "the fuel has some force?" Is it gas or water that's dripping, and where from?
- what hole in the bottom of the engine are you referring to?

Edited by tedious on 06/06/14 - 5:08 AM

Posted by Jomanchu on 06/06/14 - 5:11 AM
#3

I reread my post again and am very sorry about the lack of description. The fuel is leaking from a small hole on bottom of the engine that is connected to the Vapor Separator Tank and into the ocean. The hole is there specifically for any overflow of fuel to the VST to exit the engine compartment rather than fill it with fuel. Last season it was a small drip however this year it seems to be a steady flow of fuel. Either way it is very bad. Hope this helps a little. I have pics but not sure how to put them on here. Thanks.

Posted by tedious on 06/06/14 - 9:09 AM
#4

Joe, that's much more clear. Like I said, I'm not familiar with this particular motor, and I'd have to refresh my memory with a look at my Yamaha manual to remind myself in general how the VST systems work. With the symptoms you described, replacing the float and needle would have been my first choice too. Is the needle seat built right into the tank itself, so it's not replaceable?

Some other thoughts / questions, in no particular order:

- is the overflow hole connected directly to the VST tank? Or is it a general drain for the whole cowling, so the fuel could be coming from somewhere else?
- is what's coming out of the overflow hole straight gas, or a mix of gas and water? Not that I'd know how you could tell without an analysis.
- when the VST float shuts off the fuel coming into the VST, is the fuel redirected via some type of return line? Could that return hose be plugged, or kinked?
- is the fuel pump water cooled? Any chance internal corrosion or some other issue has you pumping water into the fuel via that path?

Tim

Edited by tedious on 06/06/14 - 10:30 AM