Cleaning Bad Gas & Water from Gas Tank

[mgmidget72]

So I've finally traced the problems (see thread here) that I was having with my new (to me) boat to there being something wrong with what was coming out of the gas tank (built-in). Not sure if it's water, old gas, or something else, but I'm draining the tank. If it matters to give an answer to my questions below, I'd have to guess that it was water based on what I saw coming out.

Will simply pumping it empty from the fuel pick-up (on mine, it's a rigid hose going down to the bottom of the tank with a metal screen filter on the end) be enough? Or should I tilt the boat and put a tube down into a corner of the tank? Or do I have to go farther and clean it somehow?

Thanks,
Scott

 

[robert graham]

Re: Cleaning Bad Gas & Water from Gas Tank

I would get(pump/siphon) every last bit of gas/water/trash/whatever out of the tank that's possible. Install a fuel/water separator, fill tank with fresh gas, check and drain separator frequently to remove any remaining trash. That's about the best you can do with a built-in tank with no drain(without cutting floor/removing tank). Use Stabil in fuel going forward, especially for lengthy lay-up periods. Good Luck!

 

[mgmidget72]

Re: Cleaning Bad Gas & Water from Gas Tank

Thanks Robert! There is a separator on the boat already. Even after just dumping it, I was still getting water out for a bit. I'm not seeing any water right now though while I'm draining out the tank.

So you don't think that just getting what the fuel pick-up can get would be sufficient? The gas itself is only ~2-3 weeks old. I filled the tank right before my only trip with the boat when I got stuck out. It's what was left in the tank by the previous owner before I bought the boat this March.

Thanks

 

[vincmm]

Re: Cleaning Bad Gas & Water from Gas Tank

there is water driers you can add to your fuel also. Watch how much you use...problem with todays fuel using Ethanol blends, fuel doesn't last. I always mix SeaFoam and Stabil for Marine engines with my fill ups.

 

[NHGuy]

Re: Cleaning Bad Gas & Water from Gas Tank

No do what he said or you'll end up doing it again.
Tilt it up on edge, really empty the tank, remove the sender and remove any more crud, then use something absorbent without lint to dry up the tank bottom corners. Then put in some fuel and suck it out through the separator. Remove the separator and check for junk. If you get some debris - keep repeating putting in some fuel and filtering it til the filter holds no stuff just gas. It's a pain but it will be worth the effort.

I didn't find junk but the filler, vent & fuel hoses on my 89 were old and probably original 2 years ago when I redid them. So I just changed em and cleaned up the anti siphon valve and vent. I think my old fuel line was a little pourous and allowing air into the system, or maybe the anti siphon or vent were clogged. It made a real difference in performance. Fuel matters.