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View Full Version : So...whats the best way to remove gas outta your tank?



m2736185
03-06-2012, 01:37 AM
so the 94 celica I bought doesnt really want to start or run for more than 10 seconds..its been sitting around for maybe 7 months. I have one of those pumps I got from autozone, but it didnt do a good job pumping out gas. he gas looks like a darker color than what it usually is. Idk if this is the problem, but its a start. The damn tank has a little over 5 gallons. Any bright ideas?


btw the car is a 94 st

CollapsedNut
03-06-2012, 01:48 AM
A long straw, puts hair on yer chest.

T-spoon
03-06-2012, 02:37 AM
Drain it. There's a big plug on the bottom. Probably takes a large hex key.. just -obviously- have a large enough container under it to hold everything you drain or be ready with the plug to stop it. If a lot of crud does come out.. you probably want to then drop the tank once everything that will drain has come out and flush it out. 7 months though.. shouldn't be long enough to cause problems unless the tank already had issues. And of course.. if it has been picking junk up you'll want to replace the sock on the pump and your fuel filter.

m2736185
03-06-2012, 05:03 AM
Thanks ill check it tomorrow. How old would gas have to be before it starts causing problems with starting without any stabalizer added to it?....6 monthsish?

T-spoon
03-06-2012, 05:11 AM
Thanks ill check it tomorrow. How old would gas have to be before it starts causing problems with starting without any stabalizer added to it?....6 monthsish?

I dunno, my supra ran with 2 year old gas in the tank. I'm sure it depends on a lot of things that I'm not even sure of.

Hipster Lawrence
03-06-2012, 05:35 AM
I wouldn't use 6 month old gas the ethanol attracts water I think. I've seen lots of carbed cars that won't start on even 3 month old summer gas. It didn't used to be that way.

T-spoon
03-06-2012, 05:38 AM
I did of course drain that two year old gas, was just sayin'.. it did start but it was a motor I was pulling anyway. :hehe:

Galcobar
03-06-2012, 06:59 AM
Ethanol absorbs water, true, but it provides more of a protective effect than a negative one. Water dissolved into a gas-ethanol solution in small amounts should have no adverse effect on engine components, while it can cause damage if it remains in a separate phase. Ethanol in the gasoline keeps water in solution.

A 10% ethanol mix in gasoline can dissolve up to 0.5% volume percent of water at room temperature before the water begins to separate out. Pure gasoline can only absorb 1/25 of that. When dissolved into the gasoline, water is an inert dilutent -- it has no effect other than taking up space. In effect, having ethanol in the gasoline gives you a larger margin of safety for the amount of water that can be present in the fuel system and not damage the car.

In fact, that's exactly what dry gas is -- an ethanol additive added to gasoline to bring water back into solution, where it can be run through the engine safely.

However, once that margin is passed, ethanol can actually be a bigger issue. Once you have enough water in the system for it to separate, it can form a water-ethanol phase which is capable of combusting in the engine, but it will create a lean AFR situation -- though that's obviously less of an issue for engines with self-calibrating AFRs. Two-stroke engines are actually at greater risk because the water-ethanol blend will displace the lubricating oil on metal engine parts, leading to insufficient lubrication.

Gasoline will never absorb enough water from the air to cause water or water-ethanol separation -- simple chemistry, the absorption will stop at the saturation point, and you'd have to go beyond the saturation point for the water to separate out. The danger over time is condensation, but the ratios required are pretty unlikely to occur. Pure gasoline would require, at 100 per cent relative humidity, a temperature drop from 100F to 40F and a ratio of 200 parts air to 1 part gasoline to produce enough condensation to cause water separation. Keep in mind that pure gasoline absorbs 1/25th the water as E10, so you'd need 25 times as much condensation to cause separation in E10.

The primary danger in old gas isn't really water, unless the container was subject to liquid water being introduced (e.g. it was left open in the rain). It's gum and varnish settling out, which is much less of a problem these days -- old refining methods meant gas was useless after a season of storage, now it's a matter of years.

Car_Barn_Bandit
03-06-2012, 07:30 AM
http://www.youtube.com/watch?v=YHa_jqxnn4o

The Captain
03-07-2012, 02:36 AM
Here's what I do. Disconnect the bottom fuel line from the fuel filter. Run a fuel resistant hose from that line to a gas can. Hook up a battery charger and jumper the fuel pump in the engine diagnostic port. Turn on key and, Taaadaaa!

l0ch0w
03-07-2012, 02:47 AM
Here's what I do. Disconnect the bottom fuel line from the fuel filter. Run a fuel resistant hose from that line to a gas can. Hook up a battery charger and jumper the fuel pump in the engine diagnostic port. Turn on key and, Taaadaaa!

+1 to this... it drains tanks quite effectively and its almost no work.

That plug on the bottom of the tank can be a bit rusty and might get crap in your tank... i would advise against undoing it...

4thgenceli
03-07-2012, 02:58 AM
I don't think the 4th gen has that drain plug

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MCcelica
03-07-2012, 08:27 AM
Tim. It's a 6th gen numbnuts.

4thgenceli
03-07-2012, 02:22 PM
I know. Everyone says the 4th gen had one to but i've never found it.

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T-spoon
03-07-2012, 04:25 PM
Well in any case, I never thought of doing it the way Cappy describes, but that sounds much easier/cleaner :)

RedRkt01
03-07-2012, 04:33 PM
Tim, you're correct. For the 4th Gener out there that wants to perform this task.....the captains way is the only easy way.

As for 7 month old gas....that is way jumping the gun. No need to drain that sucker. My ST162 sat for 5+ years and it started no problem. There are so many additives in the gas these days that I'd be really surprised to find any varnish in there. I'm not saying it doesn't happen occassionally, but I think that by and large the days of varnished gas are over.

Another thing that doesn't pahse me is water in the gas. It is true that some water can be absorbed , but if it is being atomized by the injectors whats the big deal?

Murgatroy
03-07-2012, 09:27 PM
Here's what I do. Disconnect the bottom fuel line from the fuel filter. Run a fuel resistant hose from that line to a gas can. Hook up a battery charger and jumper the fuel pump in the engine diagnostic port. Turn on key and, Taaadaaa!

Yeah, but real men just turn the car upside down and shake the fuel out.

Galcobar
03-08-2012, 12:52 AM
Yeah, but real men just turn the car upside down and shake the fuel out.

What's with all the veterans advising flipping the car upside down these days?

temperacerguy
03-08-2012, 02:27 AM
Yeah, but real men just turn the car upside down and shake the fuel out.

Close, real men use a match on the end of a stick.

The Captain
03-08-2012, 02:29 AM
Yeah, but real men just turn the car upside down and shake the fuel out.
Real men burn it out.

Hipster Lawrence
03-08-2012, 03:06 AM
Ethanol absorbs water, true, but it provides more of a protective effect than a negative one. Water dissolved into a gas-ethanol solution in small amounts should have no adverse effect on engine components, while it can cause damage if it remains in a separate phase. Ethanol in the gasoline keeps water in solution.

A 10% ethanol mix in gasoline can dissolve up to 0.5% volume percent of water at room temperature before the water begins to separate out. Pure gasoline can only absorb 1/25 of that. When dissolved into the gasoline, water is an inert dilutent -- it has no effect other than taking up space. In effect, having ethanol in the gasoline gives you a larger margin of safety for the amount of water that can be present in the fuel system and not damage the car.

In fact, that's exactly what dry gas is -- an ethanol additive added to gasoline to bring water back into solution, where it can be run through the engine safely.

However, once that margin is passed, ethanol can actually be a bigger issue. Once you have enough water in the system for it to separate, it can form a water-ethanol phase which is capable of combusting in the engine, but it will create a lean AFR situation -- though that's obviously less of an issue for engines with self-calibrating AFRs. Two-stroke engines are actually at greater risk because the water-ethanol blend will displace the lubricating oil on metal engine parts, leading to insufficient lubrication.

Gasoline will never absorb enough water from the air to cause water or water-ethanol separation -- simple chemistry, the absorption will stop at the saturation point, and you'd have to go beyond the saturation point for the water to separate out. The danger over time is condensation, but the ratios required are pretty unlikely to occur. Pure gasoline would require, at 100 per cent relative humidity, a temperature drop from 100F to 40F and a ratio of 200 parts air to 1 part gasoline to produce enough condensation to cause water separation. Keep in mind that pure gasoline absorbs 1/25th the water as E10, so you'd need 25 times as much condensation to cause separation in E10.

The primary danger in old gas isn't really water, unless the container was subject to liquid water being introduced (e.g. it was left open in the rain). It's gum and varnish settling out, which is much less of a problem these days -- old refining methods meant gas was useless after a season of storage, now it's a matter of years.

All that makes sense. But in my recent experience with fuel in GA, especially summer fuel it seems to go "bad" quicker. Summer fuel in ga smells like year old gas when it comes out of the pump.

I've had at least 3 cars towed in in the last year not running that after putting in fresh gas would run. They were all carbed v8s that had sat for around 9 months to a year.


Anecdotal evidence is the best kind right?

The Captain
03-08-2012, 12:57 PM
What's a karberaytor?

KoreanJoey
03-08-2012, 07:27 PM
Here's what I do. Disconnect the bottom fuel line from the fuel filter. Run a fuel resistant hose from that line to a gas can. Hook up a battery charger and jumper the fuel pump in the engine diagnostic port. Turn on key and, Taaadaaa!

^ Probably best for bad gas. Without bad gas I just run a line from the return line to a gas can.