Fuel Tank Issue

Throttle1971

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I have a 2005 GW 232 with two tanks, Main and Aux with two separate fuel valves on the port side of the aft. No fuel is coming from the main tank but no issue with the Aux tank. I am 100% sure that the fuel valve is open. Any idea how I can test to see what the problem could be?
 

kirk a

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So no fuel through either valve when set to 'aux'?

One thing to check is that the vent is not blocked for the aux fuel fill.
 

Throttle1971

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So no fuel through either valve when set to 'aux'?

One thing to check is that the vent is not blocked for the aux fuel fill.
It is the Main tank that isn't getting fuel. The Aux tank is fine. I don't think the vent is blocked because I filled the tank up too high, and gas was spitting out of the gap and to be best of my knowledge the vent is under the cap.
 

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It has worked before? or is boat new to you?

Did you just change something? Valves? A gas cap?


So you have two valves. So you have two hoses from the Main Tank. Thru two fittings. Two pickup tubes.
Head scratcher...hard to imagine both valves, hoses or pickup tubes being blocked.


You can rule out vent by priming/running with gas cap off
 

Throttle1971

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No changes have been made to anything. The setup is as described as above with two valves etc. Would you agree that it can't be a fuel pump since boat runs great when fuel is coming from the Aux tank?
 

DennisG01

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Fuel pump is downstream of your valves.

If your vent has a dip in it (it "shouldn't", though), then it may NOW be clogged with fuel... preventing venting. Do the "cap off" thing as mentioned above.

While not impossible, a bad valve is way down on the probability list. Especially if the issue arose shortly after filling up?
 

SkunkBoat

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to clarify...

Do you have two motors? Two 3 way valves so you can run both motors off the same tank or off separate tanks, depending on valve position.
 

Halfhitch

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The anti-syphon valve could be stuck closed. Not too uncommon on an older boat, especially if it has been sitting for an extended period.
 

Sea Shift

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The anti-syphon valve could be stuck closed. Not too uncommon on an older boat, especially if it has been sitting for an extended period.
An easy way to check this is pull the fuel line off at the valve and see if you can blow air back into the line. My 2002 does not have them, but the 2005's might.
 

SkunkBoat

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The anti-syphon valve could be stuck closed. Not too uncommon on an older boat, especially if it has been sitting for an extended period.
but again, he has two pickups per tank. Both would have to fail.

Obviously at some point soon the fuel line has to come off to figure this out.
Sounds like the OP just filled both tanks (he mentioned fuel coming out of vent in the fill).
Just be carefull because you won't have a shutoff valve if you disconnect Main tank hose from either valve
 

Throttle1971

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Boat has twin 150's with two valves that can feed both engines. You can run both engines from each separate tank or both engines from one tank. Currently only pulling gas from the Aux tank. Also two anti-syphon valves that feed inline with the two H20 filters. I will snap some pictures the weekend of June 9th and share them.
 

Throttle1971

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As promised pictures below of the fuel valves and fuel Seperators. The valve on the left is for the Aux tank and the valve on the right is for the Main tank. Would you agree that the position of the valves below is only going to get gas from the Aux tank?
 

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kirk a

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Assuming the hoses align with the color codes on them, then yes, both are pulling from same tank. But your logic is flawed the valves are not tied to a tank. Each valve has a hose to each tank, and the middle one is the one which goes to the engine. It would be more accurate to say that the left valve is for one engine, and the right valve is for the other - exact port or starboard TBD based on hose routing downstream of valve.

Switch one valve to the other side, and it will pull from the other tank.

BTW - thank you for following up with pictures. Was curious as to what you were working with.
 

Hookup1

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The "pointy" end is set to AUX tank. You are correct.

Remove filter cans, dump out, pour good gas back in and dump the water (if any). Top off with clean fuel. Remove the hose off the primer bulb. See if you can get some fuel flowing. If primer bulb is old or feels bad replace it. If you can get fuel out this way flip the valve to the other tank and try again. Repeat for the other engine.

Fuel Valves.jpeg
 

TMANN

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The filters and bulbs are after the tank distribution block. It runs fine on the aux, so they aren't the issue.

Is the main overfull?

I'd fire it up on the aux, then roll the valves to the main with fuel cap off and let it idle.

My bet is its airlocked. I'd mention other stuff first but its twins.
 

Sea Shift

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Boat has twin 150's with two valves that can feed both engines. You can run both engines from each separate tank or both engines from one tank. Currently only pulling gas from the Aux tank. Also two anti-syphon valves that feed inline with the two H20 filters. I will snap some pictures the weekend of June 9th and share them.
The "in-line" device between the bulbs and the fuel water separators are the fuel flow sensor, not an anti siphon.
 

Hookup1

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The filters and bulbs are after the tank distribution block. It runs fine on the aux, so they aren't the issue.

Is the main overfull?

I'd fire it up on the aux, then roll the valves to the main with fuel cap off and let it idle.

My bet is its airlocked. I'd mention other stuff first but its twins.
It's not that hard to confirm which setting of fuel valves are or are not getting fuel thru the filters. Just doit and know what is going on. Could be air leaks, bad primer bulb, low fuel in filter can. Work backwards from there.