Gulstream Fuel Tank Questions

Bumpye

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I'm planning on pulling the sending unit off the top of the main tank to check for sediment. It ran out of gas once as I pulled away from the dock. Was not able to restart. It's a 90+ gallon tank but it only took 75 when I filled it. Anything I should look for or be careful with? Thanks.
 

seasick

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did you check the motor mounted filter to see if it had gas in it. Was the primer bulb soft? Did you remove and drain into a clear container the contents of the spin on filter?
It is unlikely you have enough sediment to make up the space of 15 gallons of gas but you could have 15 gallons of water in the tank, a more likely condition. Regardless, since you filled the tank, you will have a problem if you remove the sender since fuel will spill out into the bilge.
Drain the spin on filter as mentioned, let that sir for 15 minutes and see if there are multiple layers of liquid. If you pumped water into the motor filters and VST or carbs, the motor will never start. The water has to be drained out.

Just remembered: If you pour the filter contents into a glass jar, you may not see different layers, it could be all water. Use your nose and fingers to test.
 
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Mr.crab

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Had the same problem with my Marlin, when purchased it a year ago drain both tanks with primer ball.
So I thought , both tanks 152 gal one took all of 152 gal the other 126 gals. Last Wednesday finally ran
out gas in 126 gal tank , it did take 152 gal when I filled up. The last 15 gal could be bad gas where the
motor won’t run, make sure you drain it.
 

Bumpye

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Thanks for the responses. After looking at the sending units and their location I've decided against removing them. The tanks and hoses all look in very good condition. Very dry from what I could see. My only thought on the above comments about water or bad gas is, wouldn't that get stirred up with the good gas and just "burn" off? I've never had a problem other than the one mentioned.
 

seasick

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Thanks for the responses. After looking at the sending units and their location I've decided against removing them. The tanks and hoses all look in very good condition. Very dry from what I could see. My only thought on the above comments about water or bad gas is, wouldn't that get stirred up with the good gas and just "burn" off? I've never had a problem other than the one mentioned.
If you are using E10 gas, that can absorb 1/2% water by volume. So if you had 50 gallons of gas in your tank, that could absorb 1 quart of water. More than that and the water settles to the bottom. Most tanks have the pickup tube slightly above the bottom of the tank. That sort of allows for a small amount of water to settle at the bottom and not get sucked up into the motor. When you add fresh gas, that helps absorb a little more water. A little is the key word here.