Gas Tank Cleaning Questions

[JayWltrs]

Questions from pics:

Think I have to pull tank or can I clean this up in place? Thoughts on how
to clean in place? Hoping it’s just scum and not rust but not 100% sure. Don’t want to disturb it any more immediately, because I need car to run next week.

 

[adawil2002]

I used a siphon into a 5 gallon screened bucket to vacuum up the loose stuff. Then replaced the in tank pickup screen then siphoned then reused the clean fuel. The trick to getting the fuel tank cleaner is removing the tank and agitating with lacquer thinner and loose change or a chain.

 

[Markos]

If you have been driving the car already I would just leave it for another day. It looks like rust to me. You should pull the tank and do a cleaning/sealing kit. Por15 makes one, as does Eastwood. I did it the hard way and pulled the tank out of the trunk with 13 gallons in it. Then I poured the gas out of the filler.

Your car is a 74 so the tank drops out the bottom. You can support it with a transmission jack or even a floor jack (if empty) and lower it down.

 

[Markos]

Btw - Harbor freight has a good fluid extractor.

https://m.harborfreight.com/23-gal-...r-62643.html?utm_referrer=direct/not provided

 

[jmackro]

Btw - Harbor freight has a good fluid extractor.

I use a simpler/cheaper style of pump (mine is Griot's #44406 for $35; it's nicer than the $10 HF model shown below ). I use it less as a pump and more as a way of starting a siphon without drinking gasoline. Invaluable for draining fuel tanks, as well as a lot of household plumbing jobs.

Agree with Markos: looks like rust, not just gunk. But that doesn't mean that it needs to be addressed immediately.

 

[JayWltrs]

Btw - Harbor freight has a good fluid extractor.

https://m.harborfreight.com/23-gal-manual-fluid-extractor-62643.html?utm_referrer=direct/not provided

Thanks. I ran the gas down to change the sender ring, & I shouldn’t have looked, but at least I don’t have much fuel to pump. On lockdown for any big projects for a while prepping house to sell. So I’ll probably try @adawil2002 ‘s method and get out the scope to get a closer look after I get the looser stuff up.

 

[JayWltrs]

I have used the cheaper style of pump (mine came from Griot's and is slightly nicer than the HF model shown below). It is less a pump and more a way of starting a siphon without drinking gasoline. Invaluable for draining fuel tanks, as well as a lot of household plumbing jobs.

Thanks. I have an old Coleman electric camp pump, but I don’t trust it around combustibles.

 

[rsporsche]

Jay, what did you take the interior photos with? internal pictures are quite clear

 

[JayWltrs]

Jay, what did you take the interior photos with? internal pictures are quite clear

iPhone X. Just stuck the corner with the cam and flash in the sender hole and took a bunch of shots. They look better on my computer screen than they did on my phone.

 

[JayWltrs]

And if anyone has ever made this work, I salute you. I'd tried it before to no avail. Thought I'd give it a go again in the cold and started laughing just trying to replicate this position. Picked up a 1x4 remnant and a hammer. A few taps and done with no damage to me or cap.

 

[adawil2002]

And if anyone has ever made this work, I salute you. I'd tried it before to no avail. Thought I'd give it a go again in the cold and started laughing just trying to replicate this position. Picked up a 1x4 remnant and a hammer. A few taps and done with no damage to me or cap.

This is the 'screwdriver trick', works like a charm!

 

[Stevehose]

Drain the tank, remove, and use POR15 tank restore kit. Works great.

 

[JayWltrs]

Drain the tank, remove, and use POR15 tank restore kit. Works great.

How bad do you think it looks, Steve? I can’t drop the tank for a while. Makes more sense for when I drop rear subframe.

 

[JayWltrs]

This is the 'screwdriver trick', works like a charm!

I possess the wrong screwdrivers or the wrong coordination.

 

[Markos]

How bad do you think it looks, Steve? I can’t drop the tank for a while. Makes more sense for when I drop rear subframe.

Doesn’t look bad at all. The fuel filter will pick up any of the particulates. Get a new filter when you do the tank.

 

[Stevehose]

Tank comes out from above, sorry, wrong vernacular. Yes new fuel filter until then.

 

[Markos]

Tank comes out from above, sorry, wrong vernacular. Yes new fuel filter until then.

Not on the US 1974 Steve...

 

[Paul Wegweiser]

Since your tank has only some moderate superficial surface rust (and not a ton of varnish or filth), you might try cleaning it with muriatic acid. It's nasty stuff and you can read up on the safety guidelines online, but it is often effective at removing rust like this in many cases. I have had BMW fuel tanks that contained 2-3 INCHES of dried, 30 year old gasoline. It looked like 5lbs of used coffee grinds inside. For THAT, you need professional techniques and materials. As a point of reference, I had a tii fuel tank repaired (leaking from rusted seam) and reconditioned for about $350 locally. I've done the old school "slosh it around with a chain inside" technique and it worked, but my rotator cuffs will never be the same. It took at least an hour to make any progress. YMMV.

Many of the fluids and techniques used to recondition and preserve fuel tanks will undoubtedly alter your DNA. Be careful and use appropriate respirator / filtering equipment! Cancer is no fun. Ask me how I know.

 

[JayWltrs]

Since your tank has only some moderate superficial surface rust (and not a ton of varnish or filth), you might try cleaning it with muriatic acid. It's nasty stuff and you can read up on the safety guidelines online, but it is often effective at removing rust like this in many cases. I have had BMW fuel tanks that contained 2-3 INCHES of dried, 30 year old gasoline. It looked like 5lbs of used coffee grinds inside. For THAT, you need professional techniques and materials. As a point of reference, I had a tii fuel tank repaired (leaking from rusted seam) and reconditioned for about $350 locally. I've done the old school "slosh it around with a chain inside" technique and it worked, but my rotator cuffs will never be the same. It took at least an hour to make any progress. YMMV.

Many of the fluids and techniques used to recondition and preserve fuel tanks will undoubtedly alter your DNA. Be careful and use appropriate respirator / filtering equipment! Cancer is no fun. Ask me how I know.

Very helpful. Perhaps I should secure the tank with the chain treatment in the back of my truck and go for a joy ride or some off-roading! I annually drained and cleaned our pool through college and used it to clean slime out of watering tanks for horses. Nasty stuff.

Cancer sucks, and I've raised money and been active in the local LLS chapter for a long time. If you're a cyclist, America's Most Beautiful Bike Ride around Lake Tahoe is the best event I've ever done, except the bear moseying out of the woods on the biggest climb--no place or energy to get away.

 

[JayWltrs]

Mother of cuss. Had to try to clean more. Anyone know where to get the resistance wire for the fuel sender? Or what gauge or size or metal it is?

I couldn’t find anything searching other than rigging to extend the connection.