How to remove stale gas?
- Thread starter RJH
- Start date
Colltech
'85 and '83
Yes, get under the car and disconnect the outflow from the bottom of the fuel tank. Catch the gas in a container that allows you to examine what comes out. It will be educational!
Look for rust, pieces of the screen, etc.
Once fully drained, consider flowing some clean gas through there to flush out the remaining nasty bits.
Ed
Look for rust, pieces of the screen, etc.
Once fully drained, consider flowing some clean gas through there to flush out the remaining nasty bits.
Ed
Dan Sarandrea (Phila)
Waitin' On Parts...
Rather than siphon, I would suggest the same thing as ecohen. There are two lines into the bottom of the FI cars' fuel tank: the fatter one is the nipple that leads to the suction side of the electric fuel pump, and the skinnier one is the return line.
I think you're going to do a better job of draining the old fuel, plus any very fine sediment, if you remove the line from the nipple that goes to the fuel pump.
Once the fuel has been drained, you could look thru the filler neck with a borescope to assess the condition of the tank. Or, with some more work, move the AFM out of the way, open up the access panel thru which the vapor lines run, and then remove the sending unit to get a direct eyeball on the inside of the tank.
Inside the tank, the other end of this nipple had what people call a "filter sock" attached to it, as a rudimentary way of keeping debris in the tank from being ingested into the fuel pump. Depending upon its condition, it may need to be removed...you'll need a set of (really) long reach pliers to snag it.
The owner's manual says the gas tank holds approx. 12.2 US gallons of fuel, so keep that in mind when draining from the bottom....depending upon how much fuel is in the tank, you may need to have several drain pans handy, and may want to use pinch off pliers or vice-grips to stop the flow while you change out pans.
I think you're going to do a better job of draining the old fuel, plus any very fine sediment, if you remove the line from the nipple that goes to the fuel pump.
Once the fuel has been drained, you could look thru the filler neck with a borescope to assess the condition of the tank. Or, with some more work, move the AFM out of the way, open up the access panel thru which the vapor lines run, and then remove the sending unit to get a direct eyeball on the inside of the tank.
Inside the tank, the other end of this nipple had what people call a "filter sock" attached to it, as a rudimentary way of keeping debris in the tank from being ingested into the fuel pump. Depending upon its condition, it may need to be removed...you'll need a set of (really) long reach pliers to snag it.
The owner's manual says the gas tank holds approx. 12.2 US gallons of fuel, so keep that in mind when draining from the bottom....depending upon how much fuel is in the tank, you may need to have several drain pans handy, and may want to use pinch off pliers or vice-grips to stop the flow while you change out pans.
jvandyke
True Classic
This is what I did to mine but eventually I had to drop it, clean it and reseal it.
You can quite easily take off the AFM and level sender. I lowered a light bulb into the tank to really see but there's obvious danger involved there, probably wiser to shine something in and look. :jedi:
If the tank isn't junk doing this should get things good, a new fuel filter and one added in the line in front of the pump and you should be good, anything that's upstream will be flushed through the stock filter in short order.
I have to do this to my kid's Porshe, we drained the tank into a bucket, it was coffee and as it evaporated there were many chunks in there.
When I did my X's tank I put the gas through a coffee filter. It clogged up instantly and left "rust dust" everywhere as it evaporated.
You can quite easily take off the AFM and level sender. I lowered a light bulb into the tank to really see but there's obvious danger involved there, probably wiser to shine something in and look. :jedi:
If the tank isn't junk doing this should get things good, a new fuel filter and one added in the line in front of the pump and you should be good, anything that's upstream will be flushed through the stock filter in short order.
I have to do this to my kid's Porshe, we drained the tank into a bucket, it was coffee and as it evaporated there were many chunks in there.
When I did my X's tank I put the gas through a coffee filter. It clogged up instantly and left "rust dust" everywhere as it evaporated.
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Crusader
True Classic
Depending on condition, you may be able to get away with a fuel stabilizer and be done with it. As mentioned though, the condition of the sock, moisture and debris are critical. I was lucky. Stabilizer and a couple of tank fulls and new fuel filter got her right. Good luck. Cheers,
MikeHynes
True Classic
Anti siphon filler neck
The later cars have a screen in the filler neck to prevent siphoning of the gas. Remember the gas shortages in the '80?
Your only choice is to remove the filler neck, or drain it out of the fuel out line leading to the pump (easiest option). Do that and put a pre filter in when you put it back together.
The later cars have a screen in the filler neck to prevent siphoning of the gas. Remember the gas shortages in the '80?
Your only choice is to remove the filler neck, or drain it out of the fuel out line leading to the pump (easiest option). Do that and put a pre filter in when you put it back together.
Two ways
The fuel injected cars have an outlet at the bottom - just get a drip pan and drain. (I did this to a FI car that I was parting, and the stuff that came out was vile beyond description).
Earlier carb cars don't have the outlet at the bottom, so you have to siphon or equivalent. Whatever you do, it helps to weight the end of the hose to keep it at the bottom of the tank. I'm not sure what year the anti-siphoning barrier came in, don't know if any of the cars that don't have a bottom outlet do have the anti-siphon thing.
Years ago I took an old Facet fuel pump, attached a length of fuel hose to it, mated the end of the hose to a few inches of mild steel bar with a hole bored down the middle..... Drop the end into the tank,let the weight of the piece of steel hold the end at the bottom, connect 12V to the pump and let it drain the tank for me.
The fuel injected cars have an outlet at the bottom - just get a drip pan and drain. (I did this to a FI car that I was parting, and the stuff that came out was vile beyond description).
Earlier carb cars don't have the outlet at the bottom, so you have to siphon or equivalent. Whatever you do, it helps to weight the end of the hose to keep it at the bottom of the tank. I'm not sure what year the anti-siphoning barrier came in, don't know if any of the cars that don't have a bottom outlet do have the anti-siphon thing.
Years ago I took an old Facet fuel pump, attached a length of fuel hose to it, mated the end of the hose to a few inches of mild steel bar with a hole bored down the middle..... Drop the end into the tank,let the weight of the piece of steel hold the end at the bottom, connect 12V to the pump and let it drain the tank for me.
Greg (in Conn)
Bertone curator - X driver
carl
True Classic
My Fiats are not usually the injected models and I use an electric fuel pump for carbs to draw out the gas into a container....a lot more controllable than pulling the plug at the bottom of the tank. Not mentioned, but another problem with cars that have sat a long time is the amount of water in the bottom of the tank, so draining the tank is a good idea if only for that reason.