Logo
FULL SITE MENU

2016 Suzuki DF15A - Leaking Gasoline

C

calebic

New member
Thank you for your patience as I begin my journey learning about my motor and how to work on it. I still have much to learn.

Currently, I'm dealing with a gasoline leak. Whenever the motor is running and engaged, a significant amount of gasoline is leaking out of a black hose that must be a vent hose normally because it doesn't connect to anything on one end. Below is a picture of the hose and where gasoline is leaking.

df15A-gas-leak.jpg


This hose travels up behind the fuel filter and connects to something on the top of the motor. Here is a picture of where this hose connects to the motor:

df15A-hose-connection.jpg


This gasoline leak issue started randomly, and prior to showing these symptoms, the engine would shut off when idling. I would also have to turn the throttle a little bit when starting the motor, as without giving it a little gas, it wouldn't start. Yesterday, I went to start the motor without giving it any extra gas, and it started normally. I went out for a ride and noticed that the engine was running faster and better than normal. Then I smelled the gas and saw that a lot of gas was leaking into the water, so I went home and started my research.

Please let me know if there are any other details I can provide to help with diagnosing this gasoline leak. From my research, it's possible this hose is a vent hose and is connecting to the VST? However, I could be wrong about this.

Any input and assistance you can offer is GREATLY appreciated!
 

Not familiar with your engine so I don’t know how much help I’ll be. The part you have circled in lime green looks to be part #6, Chamber Evaporation in the link above, hose #17 appears to vent to atmosphere. On my engine(DF 90A) the VST also vents to atmosphere but inside my VST is a float that controls the amount of fuel coming in from the low pressure pump. On your engine I don’t see where a float would be to control the volume of fuel entering the high pressure pump. My best guess is you’re getting too much fuel and the excess is getting dumped out the Chamber Evaporator (part #6), unfortunately I can’t tell you how or what controls the fuel volume. It isn’t obvious to me based on the parts page. Hopefully someone familiar with your engine will chime in.

I would recommend you get yourself a genuine Suzuki service manual, there you will find a detailed breakdown on the fuel system plus everything else you will need to know about your engine.

Sorry I couldn’t be more help. Good luck.
 
William01 said:

Not familiar with your engine so I don’t know how much help I’ll be. The part you have circled in lime green looks to be part #6, Chamber Evaporation in the link above, hose #17 appears to vent to atmosphere. On my engine(DF 90A) the VST also vents to atmosphere but inside my VST is a float that controls the amount of fuel coming in from the low pressure pump. On your engine I don’t see where a float would be to control the volume of fuel entering the high pressure pump. My best guess is you’re getting too much fuel and the excess is getting dumped out the Chamber Evaporator (part #6), unfortunately I can’t tell you how or what controls the fuel volume. It isn’t obvious to me based on the parts page. Hopefully someone familiar with your engine will chime in.

I would recommend you get yourself a genuine Suzuki service manual, there you will find a detailed breakdown on the fuel system plus everything else you will need to know about your engine.

Sorry I couldn’t be more help. Good luck.
Click to expand...
Thanks so much, William. Your input definitely helps me in continuing to research this issue. I'd say you identified the parts accurately. Now to figure out more about what's going on inside the Evaporation Chamber (#6) and how to fix it.
 
Update: I took the Evaporation Chamber (#6) apart, and it'd be hard to say this part is the issue. There is nothing mechanical inside the Evaporation Chamber, no float valve or anything of the like. It simply looks like the vent hose (#17) is higher in elevation, and in theory would allow rising fumes to vent through the hose while gasoline sits lower in the chamber. The Evaporation Chamber was clean and the rubber seal between the top and bottom parts of the chamber was supple and in the proper place.

So, now we trace backwards from here and look into the Fuel Pump (#2) and the Fuel Vapor Separator (#5).

I'm super grateful for any input or knowledge anyone can share.
 
My issue ended up being with the Fuel Vapor Separator (#5) in the diagram linked above. Inside the Vapor Separator there is a valve on a spring. In my case, the spring had come off and the valve hinge pin had come out. Therefore, the valve couldn't close to stop the flow of fuel, and the gas would just go through the Vapor Separator (#5), up hose #30, into the Evaporation Chamber (#6) and out into the water through hose #17.

After opening up the Vapor Separator, it was fairly obvious how to put the hinge pin back in and reattach the spring so the valve would spring closed. Actually a pretty easy fix once I worked backwards from hose #17.

Hope this helps!
 
Well I fixed my issue. Took the vapor separator off twice! Cleaned it TWICE! Turns out the vent hose pours fuel out of it without change! So I looked at it again… the owner before me apparently switched the supply hose with the return hose…. Soo once all plumbing was hooked up the correct way. VVvvrrruuummmmm with no leaking gas from the vent!!! Hit myself in the head with a hammer, problem solved !!!
 
I know this is an old topic ... but I am having this same issue with a DF20A after a shop visit. What were the two hoses that were switched? My guess is that the shop reversed them.
 
Back
Top