2019 DF25A leaking fuel into the water when running

[slmgtr__]

Hi Everyone,

Hoping someone could help me - I was very surprised to have fuel leaking into the lake behind the motor when it was running. The engine has about 60 hours of run time on it.
It ran fine besides that. I couldn't see anywhere the fuel could be leaking out into the water. I put my hand in front of the exhaust port expecting it to get wet with fuel but it didn't.

When I got back home, I took the engine cover off looking for gas somewhere or a wet sport but could see anything like that. I bought the engine new in 2021.

Any help would be greatly appreciated.

Many thanks
Steven

[cprice11]

Most 2 strokes don't completely burn all the fuel oil mixture and leave "rainbows" in the water, It could be that.

[Moonlighter]

Most 2 strokes don't completely burn all the fuel oil mixture and leave "rainbows" in the water, It could be that.

DF25A is a 4 stroke. 2 strokes are designated “DT”.

Steven, the first place to check is the fuel line connector to the engine, where it clicks on. Pump the primer bulb in the fuel line until its firm and run your fingers under the connector to see if there is any sign of fuel leaking there. If there is, see if you can figure out whether the hose clamp is not tight enough, or if the leak is from the join where the connector clicks on. Its possible you might need to replace the fitting on the fuel line because sometimes the seal does fail and leak.

The next thing would be to start the motor on the muffs or with the leg well submerged (at least 3-4” above the anti ventilation plate) with the cowl off. Be very careful, while you look for any signs of leaks from fuel line, engine mounted fuel filters and the like. Everywhere that a hose has a clamp on it should be checked. Your nose can be as helpful to track a leak down as your eyes.

Also, check the vent line on the Vapor Separation tank, if the VST is partially blocked with contaminants or the float is set wrong, fuel may drip out of the vent line when the engine is running.

See parts #’s 4 and 17 on the diagram at this link:
https://www.boats.net/catalog/suzuki...xxxx/fuel-pump

Good luck. Report back what you find.

[cprice11]

My bad, I was thinking about my 25 hp two stroke.

[slmgtr__]

Thanks very much for this, I'll get the boat into the water this weekend to try out your suggestions.
I really want to learn as much as possible about the engine and any kind of troubleshooting I can do myself, but I am very surprised something like this has happened so early on.
Hopefully it's just a trivial issue!

Cheers
Steven

DF25A is a 4 stroke. 2 strokes are designated “DT”.

Steven, the first place to check is the fuel line connector to the engine, where it clicks on. Pump the primer bulb in the fuel line until its firm and run your fingers under the connector to see if there is any sign of fuel leaking there. If there is, see if you can figure out whether the hose clamp is not tight enough, or if the leak is from the join where the connector clicks on. Its possible you might need to replace the fitting on the fuel line because sometimes the seal does fail and leak.

The next thing would be to start the motor on the muffs or with the leg well submerged (at least 3-4” above the anti ventilation plate) with the cowl off. Be very careful, while you look for any signs of leaks from fuel line, engine mounted fuel filters and the like. Everywhere that a hose has a clamp on it should be checked. Your nose can be as helpful to track a leak down as your eyes.

Also, check the vent line on the Vapor Separation tank, if the VST is partially blocked with contaminants or the float is set wrong, fuel may drip out of the vent line when the engine is running.

See parts #’s 4 and 17 on the diagram at this link:
https://www.boats.net/catalog/suzuki...xxxx/fuel-pump

Good luck. Report back what you find.

[Murray]

Thanks very much for this, I'll get the boat into the water this weekend to try out your suggestions.
I really want to learn as much as possible about the engine and any kind of troubleshooting I can do myself, but I am very surprised something like this has happened so early on.
Hopefully it's just a trivial issue!

Cheers
Steven

Get a genuine Suzuki service manual. It will have all the information you will ever need.

[slmgtr__]

Hi Everyone,

I tried out the motor this morning to see if I could troubleshoot where the leaking gas problem is. I'd really like to understand what's going wrong, but unfortunately when running the engine with the cover off, I wasn't able to see anywhere where the gas is leaking. I did see where it's coming out of the engine case and have attached a screen shot of a video I made of the dripping. Could the leak be coming from down below in the engine case where you can't easily see? I do believe the engine was fine at the beginning of the season, so it's something recent. I followed the guide for engine break in, changed the engine oil and the foot oil, and before storing it for the winter in a closed but unheated garage I again change the engine oil. Also, I run mid grade (89) gas with stabilizer. I have called the dealer to get an appointment to get it checked out, and it is still under warranty but over the phone they said well if the maintenance hasn't been done it won't be covered but I do it myself, so not sure how I can prove it except I buy the oil and filter from them....

Let me know if anyone has any ideas (and I thank you in advance!) I did make some more videos, I could probably figure out how to share them if that would help

Many Thanks
Steven

suzuki_leak.jpg

DF25A is a 4 stroke. 2 strokes are designated “DT”.

Steven, the first place to check is the fuel line connector to the engine, where it clicks on. Pump the primer bulb in the fuel line until its firm and run your fingers under the connector to see if there is any sign of fuel leaking there. If there is, see if you can figure out whether the hose clamp is not tight enough, or if the leak is from the join where the connector clicks on. Its possible you might need to replace the fitting on the fuel line because sometimes the seal does fail and leak.

The next thing would be to start the motor on the muffs or with the leg well submerged (at least 3-4” above the anti ventilation plate) with the cowl off. Be very careful, while you look for any signs of leaks from fuel line, engine mounted fuel filters and the like. Everywhere that a hose has a clamp on it should be checked. Your nose can be as helpful to track a leak down as your eyes.

Also, check the vent line on the Vapor Separation tank, if the VST is partially blocked with contaminants or the float is set wrong, fuel may drip out of the vent line when the engine is running.

See parts #’s 4 and 17 on the diagram at this link:
https://www.boats.net/catalog/suzuki...xxxx/fuel-pump

Good luck. Report back what you find.

[slmgtr__]

Get a genuine Suzuki service manual. It will have all the information you will ever need.

I can't seem to find one for sale in Canada, do you know where I can get one? I did find a free version but it's for old model year (I think 2002 or something like that)

[Murray]

I can't seem to find one for sale in Canada, do you know where I can get one? I did find a free version but it's for old model year (I think 2002 or something like that)

Likely have to go through a dealer.

[slmgtr__]

I keep thinking about this - doesn't it have to be leaking from either a fuel line or the fuel filter? Yet the engine runs fine so it's not being starved of gas, I can get up on a plane fine. It's on the back of a 16ft Lund SSV aluminium boat. Once it exits the fuel filter, isn't it then going to the injector? Could an injector leak? I hope it's not that!

[slmgtr__]

Hi Everyone,

I did some more troubleshooting and it looks like the gas is coming out of the exhaust, please see the pic below. Is this possible? You can see how it's all wet around the exhaust.
Is the engine just running too rich and the gas isn't getting properly ignited? I wiped the streak with a white paper towel and it was the color of oil but it 100% smelled like gas and has the viscosity of gas not oil.

suzuki_leak2.jpg

[ShellKnobCat]

I am having this same issue with my 2019 DF-140A. It is intermittent and began late last season. There is no fuel leaking anywhere that I can see, feel or smell with the cowl off while the engine is running or after it stops. When it does happen an obvious sheen of fuel appears around the motor along with a strong gas smell. I asked my mechanic about it and he suggested the running rich thing but I would think that would be constant and not intermittent. I had the boat out of the water last week and ran the engine on muffs several times but no leak was present of course. I have checked all the gas lines and fuel tank (2019 Landau tritoon) but no leaks there. Oil level is not rising and no gas smell in oil. The motor runs great and fuel consumption seems to be same as always.

[ShellKnobCat]

Bumping this, getting ready to pull the boat off the lift and try to figure out the gas leak. Any pointers on what to look for are appreciated. The leak is coming from under water, there are no leaks to be found anywhere under the cowling, no gas in the oil and the engine runs great. 2109 DF140A 625 hours.