1999 Volvo penta 5.0 gi TBI float in Fuel reservoir vapor separator tank

bannditt

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Joined
Oct 29, 2006
RO Number
24074
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If I manually fill up the vapor separator tank with gas the engine will start an idle perfectly until the fuel runs out of that tank then the pump will start to squeal so I immediately shut it down I did that a couple of times I have two new fuel pumps installed high and low pressure I know there is a float inside the vapor separator tank do you think that float can stop the fuel from filling up the vapor separator tank? There is no blockageFrom the main fuel tank through the filter to the low pressure pump
 
I'd say the problem might be upstream of the vapor separator tank and pumps. Sounds like a restriction in the fuel supply,
check the anti siphon valve on the fuel tank, the fuel lines to make sure they are not collasping, and the tank vent. Something is causing the pump to work overtime...
 
Thanks Lou Went through the whole system from the tank all the way to the throttlebody everything checks out so I tried running the boat on just a can of fuel and it ran I think I have water in the bottom of my tank and the high pressure pump was definitely shot, i’m gonna be keeping the boat so I changed both pumps I took the vapor vapor separator tank out to check the float to make sure there was no corrosion in there it’s fine,I couldn’t pull the pick up out of the fuel tank might be a baffle or something on the bottom of the pick up but I blew in it and it was clear then I blew in it when it was in gas and gas splashed up in my face the vent is also clear
 
If you can remove the cover for the fuel tank sending unit (just be careful 5 screws or bolts in that circular cover) and lift the fuel gauge float out, you most likely can see down to the bottom of the tank, and then siphon out any water you find down there. I actually did the same thing during Hurricane Sandy to get gas for our generator, had 40 gallons in the boat when the gas stations couldn't pump fuel.
 
So you’re saying wait for a nice calm day and just drain the water out of the bottom of the tank?
 
So you’re saying wait for a nice calm day and just drain the water out of the bottom of the tank?
How much gas and is it E10 or E0?

The alcohol in E10 gas will absorb water to a point. With small amounts of water you are fine.

If there is a lot of water in E10 them the alcohol will absorb the water and come out of solution from the gas. What it cannot absorb will also be on the bottom of the tank You are left with water & alcohol on bottom of tank and gasoline that is probably 80 octane on top.

I would consider pumping out the gas and filling with fresh gas.

People who deliver fuel oil & gas have a paste that they put a little on a stick and put the stick in the fuel tank and the paste turns a specific color if water is present.

Have you changed your fuel filter dumping what was in the filter into a clear glass jar to have a look.
 
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I’m fine as long as I manually feed the vapor separator tank I am running off a can of gas to bypass any problems from the fuel tank the lines look OK not broken or pinched when I had it running I removed the low pressure fitting and hardly any fuel was coming through
 
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