Replace Gas Tank Vent

[mejim707]

I have a 96 Seadoo Challenger. I've had an issue in the past where after running the boat on the water for a while, if I shut it off on the water it wouldn't start up if I let it sit for a while. Someone suggested that the gas tank vent may be the issue not allowing the fume build up to escape and instead creating positive pressure in the tank forcing extra fuel into the cylinders and flooding the engine. I'm not sure how much truth there is to this but just to be on the safe side I'm thinking about replacing the vent. It looks easy enough. The only issue is that the part is unavailable / discontinued. However I did fine this part on amazon. Do you think this will work? It looks more durable and higher quality.

https://www.amazon.com/Sea-Dog-352110-1-Tank-Vent/dp/B000ZFUYOM
Thanks

 

[noviceskier]

History on the boat? Carbs ever been rebuilt?

 

[mejim707]

History on the boat? Carbs ever been rebuilt?

Yeah, complete rebuild and pressure tested. Also did compression tests on the cylinders and they’re both like 145. There’s no air in the fuel lines either.

It starts just fine if you shut it off fora few minutes. But any extended period of time it gets flooded. I pull the plugs and they’re wet.

But when it’s running it runs like a monster. Awesome boat.

 

[FlyboyX]

How do you gas up your boat? Do you trailer it to the gas station? If your vent were plugged, You would have a lot of trouble with the pump constantly kicking off. Also, when you get completely full, it should shoot gas out the vent.
If it is plugged, I would suggest taking the oem unit off the boat and cleaning it rather than replacing it with some unknown aftermarket part.

 

[mejim707]

How do you gas up your boat? Do you trailer it to the gas station? If your vent were plugged, You would have a lot of trouble with the pump constantly kicking off. Also, when you get completely full, it should shoot gas out the vent.
If it is plugged, I would suggest taking the oem unit off the boat and cleaning it rather than replacing it with some unknown aftermarket part.

I fuel up at a gas station. I’ll do as you suggest and pull the oem part and clean it.

 

[motoring]

i have same problem
have you fixed it yet ?

 

[motoring]

for the moment i installed an inline fuel valve to turn off after each time motor is shut down

 

[motoring]

i rebuilt carbs wth good oem kits

 

[mejim707]

I haven't had a chance to test it yet. I need to get it to the lake. Maybe this weekend. I'm going to run it around for 30 minutes, head back to the dock and park it for 15. If it fires up I should be good.

One note, when I got the boat it had starting issues. The OEM starter was not working, along with the ignition solenoid. I pulled the OEM starter and tested it. It did not work. So I bought a new after market starter off Amazon.. Stupid mistake. I got one season out of it.

What I noticed was the new starter had 9 teeth on the gear. While the OEM one had 8. I looked it up and apparently when these boats were new and used to race they had trouble starting on the water after being run for a while. Seadoo ultimately changed the starters with the 8 tooth gear ones to fix the problem, like the one I removed.

I recently rebuild the OEM starter and put it back in. Start perfectly. Not I need to test it on the water. I'm hoping that perhaps this could be a contributing factor when the engine is turning over, but doesn't have enough torque. Then after many failed attempts it floods.

When I hit the water I'm going to run it for 30 then dock it. Turn off the fuel, open the fuel cap a little to make sure fumes aren't building up. After 15 I'll attempt to start it. If it works I'll do the same thing again but this time I'll leave the fuel cap tight. If it starts after 15 minutes then I know the starter was the issue. If not, then back to the drawing board.

 

[mejim707]

i rebuilt carbs wth good oem kits

All the fuel lines are new black, not the gray ones. New fuel filter, complete carb rebuilds with OEM rebuild kits. Pressure tested to correct PSI. Compression on both calendars is also good.

Another thing I was thinking about too was when I rebuilt the carbs I build my own pressure tester. If that didn't work properly it would have screwed up the pop off tests. So if this issue persists I may have to buy a factory pressure gauge and pull the carbs again. I don't want to do that lol Hanging upside down in that engine bay for hours gives me a raging headache.

 

[motoring]

I haven't had a chance to test it yet. I need to get it to the lake. Maybe this weekend. I'm going to run it around for 30 minutes, head back to the dock and park it for 15. If it fires up I should be good.

One note, when I got the boat it had starting issues. The OEM starter was not working, along with the ignition solenoid. I pulled the OEM starter and tested it. It did not work. So I bought a new after market starter off Amazon.. Stupid mistake. I got one season out of it.

What I noticed was the new starter had 9 teeth on the gear. While the OEM one had 8. I looked it up and apparently when these boats were new and used to race they had trouble starting on the water after being run for a while. Seadoo ultimately changed the starters with the 8 tooth gear ones to fix the problem, like the one I removed.

I recently rebuild the OEM starter and put it back in. Start perfectly. Not I need to test it on the water. I'm hoping that perhaps this could be a contributing factor when the engine is turning over, but doesn't have enough torque. Then after many failed attempts it floods.

When I hit the water I'm going to run it for 30 then dock it. Turn off the fuel, open the fuel cap a little to make sure fumes aren't building up. After 15 I'll attempt to start it. If it works I'll do the same thing again but this time I'll leave the fuel cap tight. If it starts after 15 minutes then I know the starter was the issue. If not, then back to the drawing board.

what happens is the cylinder hydrolocks and it wont turn over or if not totaly hydro locked its to flooded to start what i had to do is put the plus wires grounded and put a towel over the cylinder heads after i removed plugs spin the starter and the gas will shoot out then i installed plugs and a shot of start fluid and it fires right up.

 

[motoring]

the ski sat for a month or more with 5 gal it started right up no choke even. carbs rebuilt good. ! after i filled tank all the way put ski in water she flooded out . so with the full tank full it floods out so to ease my work on a 95 degree day i figure the fuel shutoff will work.( i remove my three way valve to troobleshoot lean condition now its a rich condition flooding but the engine can live with a rich condition i may not but thats the way it is for now lol) until i figure out why its flooding. im thinking the same as you. a bit of pressure from tank is cuasing the flooding . ive cleaned the check valves (the ones for the fuel thank system)many times in the past and evrytime i check them their stuck until they pop open with my air pump but i check them a week later and stuck again. so im going to try removing the one that allows air into tank and see what happens to flooding. i did open up the pto carb and the check valve didnt break etc its good. never had a 100 percent good day with the 3 seasons i had used this ski. this is the best season so far one run ... new oem carb parts the motor ran greatlike never before.. until my exhaust clamp blow off .

 

[motoring]

the valve your looking to by isnt a one way its just a vent. it will have the same effect as removing the factory . the factory one will let air in but not out i guess seadoo wantsa the tank to have some low pressure the othe check valve pops open if pressure gets to high .it will allow air out only if over i believe 1.5 psi. and ive pump up my tank to about .5 or up to 1psi and the tank really starts to ballon so i never pumped tank enough to pop open the valve . i remove valve from ski before i pumped it to pop open. just my experience im sure someone will say im wrong lol im never 100 percent correct.you dont want the air to vent inside the hull the part your looking at will give you a way to have the hose vent outside hull. the hose size my not fit seadoo hoses

 

[motoring]

could also be the bellows is pushing the needle jet open i think i have to check pop off again

 

[motoring]

well since i responded . my skii has been running great after carbs rebuild i took apart pto carb from back side everything was corect . i have been carefull to close the fuel valve and she start up one crank and runs 100 percent perfect ,as far as flooding it certainly dont do it when the fuel tank is half full ,with valve open... i check to see if she floods again once i fill tank to top again.