Best DIY way to drain gas tank?

[darylann]

We finally figured out why my port engine won’t run. I’ve got spark and the carburetor is getting gas, but we can’t keep it going without starter fluid. Upon collecting some of that fuel in a jar, we learned that I’ve got water in the gas tank (from storage for too long without stabilizer in the tank… lesson learned!). There’s probably only 10-15 gallons in the tank now (not sure because gauges don’t work).
Some say just add a bottle of Heet and about 15 gallons of gas and I’ll be good to go. Others say NO, drain that tank to get all the water out before putting good gas in! I wish the Heet would be a quick, cheap and easy fix, but I’m thinking draining it would probably be best.
Opinions? Suggestions?

[tomschauer]

Drain that tank!!!

[bud37]

Yup I agree, drain that bad stuff out.....ain't no magic in a bottle.

[g36]

Use a small electric fuel pump like a Mr. Gasket 12S Micro Electric Fuel Pump to drain into portable jugs. Something like $30 on Amazon. could remove the gas tank sender and drop a tube to get most out or hook it up to fuel line which will leave some. I've set up a remote switch to control mine, you must be concerned with sparks but this pump will do great.

[Midnightsun]

Do you not have water separating fuel filters? these should fill up before you have running issues. Had this happen to me many years ago when coming back on fumes in very agitated waters. Lesson learned and to this day carry spare filters on board. With only 15 gallons remaining (maybe only a few) and the boat movement, even small quantities of water will get picked up and gradually fill the filter leading to poorly running to no go.

The boat I referred to the, tank was never drained, the boat continued with the second owner for close to 10 years with no water/gas related issues. Just saying it could be a very quick fix.

[km1125]

QR_BBPOST Use a small electric fuel pump like a Mr. Gasket 12S Micro Electric Fuel Pump to drain into portable jugs. Something like $30 on Amazon. could remove the gas tank sender and drop a tube to get most out or hook it up to fuel line which will leave some. I've set up a remote switch to control mine, you must be concerned with sparks but this pump will do great.

^^^THIS.

I was wondering if my tanks had collected any water, so one year I ran the tanks down below half on each then I used a 5' copper pipe connected to a similar pump and was able to lower that pipe down into the tanks from the fill port (it was a straight shot right down into the tank). Ran that through a water-separating filter and then pumped it into the other tank, until I drained it completely empty. Then, I reversed the process pumping all the fuel back, completely emptying the other tank. I ended up finding absolutely no water so I was happy.

If you don't have a straight shot in from your fill port, you might have to pull the fuel level sender and lower a hose that way.

Do not do the HEET and more gas thing

This is the rig I built (was only about $80 IIRC)

fuel_polishing_setup.jpg

[darylann]

Do you not have water separating fuel filters? these should fill up before you have running issues. Had this happen to me many years ago when coming back on fumes in very agitated waters. Lesson learned and to this day carry spare filters on board. With only 15 gallons remaining (maybe only a few) and the boat movement, even small quantities of water will get picked up and gradually fill the filter leading to poorly running to no go.

The boat I referred to the, tank was never drained, the boat continued with the second owner for close to 10 years with no water/gas related issues. Just saying it could be a very quick fix.

Great info… Thanks for sharing! I will check this out for sure! Every time something goes wrong on my boat, it’s a part of a system I haven’t worked on yet and a total learning process. I’d like to do as much work as I can myself, so I can learn every inch of my boat and maintain it myself when possible. Thanks again!

[Midnightsun]

The filters will be the first thing to look at for sure. As they accumulate water over time it gets to a point where they are full and overflow into the engine. These should be changed every year however most tend to skip one or two. I would change the filters and see how she runs, pretty sure you will be fine.

If it starts sputtering next season this would indicate enough water in the tanks so you may need to empty them however my gut feeling is it just sucked up enough water over X amount of time running on nearly empty tanks and since you never changed the filters, this is what happens.

[Dewmyster]

I had a similar issue in another boat. Wasn't a Carver but I knew I had a lot of water in a port tank. Used a piece of 36" hard pvc that fit into a 3/8" pvc flexible hose and siphoned ii into a Gerry jug in my bilge, thru the fuel line. Took 20 gallons of water fuel out.......left the gas cap off on one side. Green water over the bow and down the sides for an hour until the port engine dies. Took a couple of days and then loaded the tank with 94 octane ran fine after that.