Water in fuel tank?

Hi, I just got my baja delivered from Brisbane today. When they picked it up from home it was running fine, then they took it to their holding yard where it sat for a week. They told me it was going to be under cover. Then they rung me the other day because they couldn't start it, but managed to get it on the truck somehow and it was left to me to get it started today. I got the thing going but it runs very rough and backfires through the exhaust like it's got a blocked jet, but I checked them and they're fine. Checked the pugs - fine, leads - fine. I think it's either got water in the fuel, or the fuels gone off. Any thoughts before I drain my tank?

try putting metho into the tank to dry out the water in the fuel🙂

Put some of the fuel on your hand, if it feels cold then the fuel should still be ok....if it doesnt feel cold on your hand then its no good.

If there is water in the tank then Metho will do the trick for you

Excellent, thanks guys, but how much metho? I've got just over 1/2 a tank, so maybe 250ml?

Personally, I wouldn't recommend metho. But I definitely would recommend putting some methanol in the tank. Methanol absorbs water and still mixes with the petrol properly, and it makes your motor feel like new too, with the extra power and all. Also cleans the intake, cylinders and axhaust too. It's the stuff you run model aircraft on in case you're wondering, and you get it from a fuel depot, or a mate that flys model planes. (make sure it's not premixed with oil and nitromethane)

Drain the tank into a bucket and see if there is any water in there.

Keep the tank cap off and outlet pipe as well. Stick the car in the HOT sun for a few hours it will evaporate out, no problems.

While you have it off also disconnect the fuel line at engine end and blow out with compressed air, use a rag over the end to catch what ever comes out of the line for checking purposes.

glad I saw your posting, as i have the same prob with my bug. I have already tried the metho but didnt use too much, I was a bit worried about putting metho in the fuel tank. still having the same prob a week later, back firing and no power. I shall get the hubby to drain the tank next.

Petrol will evaporate faster than water due to it being more valatile at lower temperatures. On top of that, the petrol floats on top of the water, so the water will be at the bottom, although you won't get it all out without removing the tank and turning it upside down... With good old methanol, otherwise known as methyl alcohol (not metholated spirits) you can safely run 10 to 15 % in your petrol. I used to run 20% in my old Torana with water injection as well. Really gave her some zing (as the methanol burns faster and helps the water expand as steam and drive the piston down faster, so it's like turbocharging your motor).

I would be careful using methanol as it is hygroscopic (absorbs water from the air). This can then lead to corrosion of your whole fuel system. A lot of drag cars that run methanol have to drain their whole fuel system after use.

64vwmark wrote:I would be careful using methanol as it is hygroscopic (absorbs water from the air). This can then lead to corrosion of your whole fuel system. A lot of drag cars that run methanol have to drain their whole fuel system after use.

Errr... thats why you use it - to absorb the water from the bottom of the petrol tank!

I picked up some water in my Premium petrol yesterday from a service station. Bl;at BLST Burrrp,ding,...burrppp,... blat! Grre... BLlat! It really SUCKED as my car conked out on a blind corner on the Old Pacific Highway north of Sydney in among all the motorbikes on a Sunday afternoon... Guessing, I drained a litre or so of fuel out of my fuel line and filter (from the engine end) and all was good within a couple of minutes :thumb

Errr.... lets look at it this way.

Lets express methanol as MeOH. When MeOH dissolves in water it forms a basic solution of methyl ions and hydroxide ions. Me+ and OH-.

Now lets consider aluminium which is amphoteric ie. dissolves in acids and bases. Alumina refineries use another base, Sodium Hydroxide (ok it's much stronger), to extract aluminium from Bauxite. Think of how many aluminium (or aluminium alloy) parts are in most VW's. I don't think I would be exposing them to methanol too often. Maybe once to get you home.