I accidentally left the gas cap off and cover open on my 2001 XK8 before my area received heavy rain for several hours. I don't know for sure or how much, but water had to have gotten in my tank, I assume. Am I able to drain the tank myself or would a product like Heet be sufficient?

 

Buuuuummer!!!

Heet and dry gas products are more for regular condensation that builds in the tank than for significant amounts of water...

I would guess you'll need to be draining that tank.

Maybe it can be drained at the fuel rail? If the pump will run key in on position? OR run a hose and pump or syphon the gas out. Syphon will certainly leave some behind BUT it might be a way to see if you find h20...

In my (limited) experience, draining the fuel on an xk8 is no easy task. I can think of two directions that I might go. One would be to go after the the connection at the fuel filter. I don't know if they are all the same year to year,,, but in the well of the LH tire - from what I understand. Disconnect one of the hoses and see if turning the car to position iii (or ii) will run the pump. The other option would be to get to the area where the fuel lines leave the top O the tank. In that a steel/aluminum wall support would need to be removed and then some push and pull on the tubing up there,,, with an extension hose,,, to get the water/gas into a vessel of some sort. Still, again, that is depending on getting the pump running without the car being started...

I would resist,,, unless absolutely necessary,,, going under the car to deal with the very differcult to reach fuel line to tank connection.

Fuel rail,,, filter,,, lines at top O the tank....
My 2cents.

 

I appreciate your quick detailed response and advice. I think the siphoning suggestion is the one I am most comfortable with. I am not mechanically inclined, so the draining at the hoses or filter sounds far to intensive for me. I thought I would siphon maybe a half gallon or more, making sure the hose is at the bottom, since water is heavier, to see how much H2O is or isn't present, then proceed from there. The nearest Jaguar dealership is 80 miles away, so that isn't an option.IUOTE=JayJagJay;2206062]Buuuuummer!!!

Heet and dry gas products are more for regular condensation that builds in the tank than for significant amounts of water...

I would guess you'll need to be draining that tank.

Maybe it can be drained at the fuel rail? If the pump will run key in on position? OR run a hose and pump or syphon the gas out. Syphon will certainly leave some behind BUT it might be a way to see if you find h20...

In my (limited) experience, draining the fuel on an xk8 is no easy task. I can think of two directions that I might go. One would be to go after the the connection at the fuel filter. I don't know if they are all the same year to year,,, but in the well of the LH tire - from what I understand. Disconnect one of the hoses and see if turning the car to position iii (or ii) will run the pump. The other option would be to get to the area where the fuel lines leave the top O the tank. In that a steel/aluminum wall support would need to be removed and then some push and pull on the tubing up there,,, with an extension hose,,, to get the water/gas into a vessel of some sort. Still, again, that is depending on getting the pump running without the car being started...
That was my line of thinking as well....to siphon out maybe a half gallon, making sure the hose is all the way to the bottom and see how much water is or isn't there. Draining the tank at the hoses or filter sounds way to intensive for I've not had much experience working on cars or with tools, and the Jaguar dealership is 80 miles away.
I would resist,,, unless absolutely necessary,,, going under the car to deal with the very differcult to reach fuel line to tank connection.

Fuel rail,,, filter,,, lines at top O the tank....
My 2cents.[/QUOTE]

 

Haha... I'm on my phone, writing you while at work, getting paid by the hour. No worries, Steve...

In the last 2 or 3 yrs messing around with a BUNCH of really nice but neglected cars (ones like ours and others) what I am about to say next could be on,,, could be off. I can't fully remember. BUT,,, and I hope I am wrong, I think there is some kind of blockage set up in the filler neck that prevents one from getting a line into the tank. Again, I could be wrong.

Steve,,, unless ya got a fat job, you're going to need to get dirty AND make a trip or 50 to harbor freight tools. It's the nature of these cars. They break banks AND there is huge joy and satisfaction in doing the work. Specially if it's not your primary car. You CAN do it! I live in NYC,,, I'm old. Hadn't touched a car in many ah year. I got this XK8 with a dropped valve seat. Needed a new cylinder head. I had NEVER...

Amazing dudes here walked me thru doing the job (as my first job on this car) in front of my house on the street with freshly bought tools. It's possible.

None of the approaches I mentioned are beyond your abilities... Thing is, I don't know if they are the right approaches... Hopefully someone on here will tune is both up as to what to do,,, and more importantly NOT DO. It is gasoline after all.

All will be well.
​​​​​​

 

How much fuel was in the tank? If it was less than about half, just take the fuel sender of of the side of the tank and siphon it out from there.

 

And for taking the time to share your knowledge..Yes, there's less than a quarter of a tank. Can you tell me where this fuel sender is located and how to get to it.?

 

Before you drain the tank, are you seeing any sputtering or any apparent changes in the engine performance?

The reason I ask is that a quick calculation suggests that there may not be much added water in the tank. Say it rained 1 inch over the time you had it open (25.4 mm). The opening is about 1.5 inches in diameter (38 mm), giving an area of about 1.8 in^2 (1140 mm^2). That would give you a volume of water of about 1.8 in^3 (29,000 mm^3) of water over the rain time. Now, you'd have to be fairly unlucky to get this amount since the hole is not going to be directed toward the rain at all times, probably less would have gone in. That's about 0.03 liters of water out of about 19 liters in a quarter tank (0.15%). Keep in mind, E10 gas already has water in it, varying around 0.5% (~0.1 Liters). So, even if it rained a couple of inches over the time allotted, you'd not be doubling the amount of water already in it. If you are having no issues with performance, and you went and filled up, you would dilute it even more, probably merrily going along your way.

Note: you'd need to fill up with E10 or E15 gas (thus adding alcohol to better getter the additional water).

 

Good morning Bass... Brother I ain't merely trying to disagree with ya here but,,, isn't the concern where the water gathers? At the bottom of the tank, at the pickup? If it sucks only water seem like that could be trouble.

 

Ages ago that might have been a problem here, before the days of ethanol, but if his ethanol water carrying capacity is more than the amount of water he accidentally 'spilled' into the tank, he doesn't have a problem. So, that is the first question, is there currently evidence that there is too much water (sputtering, not running at all). If not, the second notion is to increase the water carrying capacity of his fuel by adding more ethanol-based fuel.

Here E15 is better than E10 (but maybe not necessary), and higher temperatures are better than lower, but one rarely has control over that...

 

All good points.
Do water and ethanol fuel mix homogeneously? If you know what I mean,,,,

I don't know exactly how it happened (maybe I do, lol) but when I started working on the flooded (h20) XKR there was water (lots) in the tank. When I removed the fuel pump housing I could see the water/fuel line of separation... When I pumped the gas/water mix out,,, left it in the container,,, it took a bit but it RE-separated in short time.

I wanna know if the OP-er has started the car now...?
Have ya, good Brother? Have you started it or tried?

 

There's a limit to the water carrying capacity of ethanol mixtures in gasoline. When below that limit, it's essentially fully mixed. Above, the water separates. It's temperature dependent too.

For example, 95% ethanol, 5% water will almost certainly run your car at outdoor temperatures ~20-25 C. So, in that case, you could carry almost 4 liters of water without issue if you dumped pure ethanol into an empty tank. You need to be careful in Alaska in the winter with this approach, and it seems like a waste of good ethanol...

On the other hand, you could use acetone or something else to increase the water carrying capability, but you get into issues of combustion by playing with the hydrocarbons too much. At that point, you're probably better off draining the tank. Here, the amount of water seems small compared with the ability of ethanol to carry it off.

 

Super interesting! Thank you Man!
In that sense, maybe the question about a product like "heet", dry gas, will help...?

 

Probably, but if he's having no issues, just more gas would probably be okay.

 

Having recently replaced the fuel pump on my '02, I can tell you that siphoning the gas out is nearly impossible unless you pull the fill hose loose and remove the inner hose, The siphon device from Harbor Freight didn't work for me. Since the fuel pump still works and sits at the lowest point in the tank, disconnect the fuel filter (mine is under the car in front of the left rear wheel well) , connect a hose to the open fuel line and let the pump do the work by turning the ignition on. If there is water, it'll pump out first.

 

disconnecting at the filter and pumping with the use of the key/electric fuel pump sounds the easiest however it will leave some in the tank below the pickup tube.
you could do this then throw in 3 cans of seafoam and a heavy dose of stabil 360 as an over abundance of caution. these products will not conflict with each other and will have other benifits as you drive/ burn THE ENTIRE TANK OF GAS PRIOR TO FILLING UP AGAIN.

just some thoughts...

max & XKRFACE

 

ps...A NEW FUEL FILTER !!!!!!!!!!! after burning the entire tank of fuel

 

MaxTorq, There isn't a pickup tube, the sock filter sits on the bottom of the tank and is directly attached to the pump. There isn't much space between the pump and the bottom of the tank, so when the tank is empty, it's really empty.

 

Yup...