So I have spent the last 45 minutes or so trying to search for a thread about cleaning out your gas tank but to no avail. So here I am now making a thread that will hopefully get me some answers.

Ive been having fuel issues with this car since I upgraded to a full racing beat intake from air cleaner to manifold. My mallory fuel pump has been SCREAMING loud, I changed out a bunch of the smaller metal lines to larger rubber hose to reduce restrictions in the flow and recently got around to changing the fuel filter. The fuel in the thing was a disgusting brown. After the filter change the car ran great, revved freely with no stumbling and the such. Anyway, two days later it is doing the same thing it used to and it seems the filter is clogged again.

Long story short, I need some advice on how to clean my fuel tank. I am not looking forward to dropping the tank. What products or techniques should I use to un gunk my tank? Thanks in advance.

 

There's several approaches to this, 1 of them being the do-it-yourself cleaning/sealing kits.

Best option I see is to go to a radiator shop, they might be able to boil the tank out. Might take a couple of weeks to get rid of all the crud. Then they should be able to seal it inside and out.

It's guaranteed not to leak. Should be anywhere from about $150.00, to about $200.00. Some of the kits are cheaper but if the 'crud' is pretty stuck on, they won't do much.

I would def. do that before cutting it open and doing anything like that.

 

I just had my tank cleaned and sealed at a radiator shop for $100. That was cheaper than a kit to do it myself and a lot less hassle. It took them 4 days because they had to seal it twice. I went through a fuel filter a day for about a week before I finally had it done. Haven't had a problem since. Unfortunately with that approach there is no way to get around dropping the tank, sorry!

 

There are a couple fuel cleaners on the market. STP, Chevron, and 3m all offer fuel cleaners, but I believe you best bet is to drop the tank and have it boiled out.

 

I helped a friend do his 70 something Porshe 911 gas tank. He had bought it used w/ 75xxx miles. After we got it out we found the factory paper tag, several stones of various sizes, a balled up piece of packaging paper, and sand in it. Took it to a radiator shop in Buena Park, CA (Mattson's I believe). Took about 2 days and it came back better than new. If your unsure about whats in it I would go this route. Especially if you let it sit for extended periods. Gas turns into a gel after awhile. Cost about $125

HTH.

 

There are several threads on this- I did one last year. I had the tank out of my '83 (12A) cleaned at a radiator shop ($40) and they didn't get all the gunk out of it. So, I dropped it again and used a kit that contained Marine Clean, Metal Etch and a POR15 sealer. The kit was about $65. This was about a 3-day process. No problems since.

- David

 

^ I've used the POR-15 kit to clean and/or seal multiple tanks. Worked great each time. If there were no holes in the tank, I just use the Marine Clean. Boil a large pot of water and add it and Marine Clean in a 4:1 ratio. Slosh it around then let it sit over night. I do this 3 or 4 times letting the tank sit in a different position each time (right side up, upside down, on each end). Rinse well then dry with a wet vac hose plugged into the blower side and the fill hole in the tank for many hours. I've cleaned some extremely nasty tanks this way.

http://www.por15.com

 

Muriatic acid straight, with a piece of chain to shake things up. Let it sit,then shake it around, don't breath the fumes. Rinse out with lots of water, drain totally. Pour in rubbing alcohol, it absorbs the water and can mix with gas. Drain it all out let it dry while, replace in car.

This will get you by but its best to get it sealed inside when you're done. If you try to seal it yourself be careful of plugging you pick up tube.

 

I have a short length of chain. Where do I get muriatic acid?

 

Hardware store.

 

at a dead show.

 

Radiator shop is the best way. Taking the tank off and putting it on is not hard.

 

Ive been asking around and doing some searching online but I cannot seem to find a radiator shop around these parts. I am assuming there is another shop that might not specialize in radiators specifically but may have the equipment. Anyway, does anyone have a link where I could perhaps purchase a new tank online or perhaps a fuel cell instead? I would seal the tank up myself but short of starting a campfire outside of my barracks I have no way of boiling water and keeping the tank sitting safely without getting yelled at by someone of higher rank than me.

 

hardware store or swimming pool supply store

 

I looked everywhere for a new tank....Mazda said they could get me one...out of Canada for about $1250...LOL I didn't pay that much for the car! Good luck on your search!

 

ive also heard of taking the tanks to an airport and having them srap the inside with what they use in the airplane tanks. i was looking to do this, and may still do so in the future when i have to prep the SA tank for boost.

also, use rubbing alcohol or acetone to absorb the water left in the tank. rubbing alochol being cheaper.

 

I dropped the tank last night, after draining the last few gallons of fuel out of it, which came out all brown and disgusting. I was surprised to find that the tank did not look gunky and rusty inside like I had thought... I may just try running hot water through it from the pressure washer at the shop here for a few days and see if that helps at all.

 

If I were you, I'd atleast buy one of the cleaning/sealant kits availible while you have the tank down. If the boiling water works, great, but if you do all that and get it back up there and it's still clogged... it'll be kind of a waste. Plus I don't trust just boiling water, without resealing it afterward. But that's just my opinion. I'd worry too much about it rusting out later.

 

I can not condone the use of water in a fuel tank. It was the water that caused the rust in the first place. I tried a water rinse years back and now I am paying the price.

 

Buy the POR-15 kit. It works great! I did it to my 84, it took three hours to prep, and 96 hours to cure. Follow the directions, and you'll be fine.

 

get an old throttle cable, hanger, or something andrun it through the tubes on the tank. i did this when i dropped my SA and a huge chunk or rust popped out.

 

+1 on the POR-15 (found at www.por15.com)
I did that to an extra tank for my '85 GSL-SE and it made it look extremely good. The guy that sold me the tank told me to tank a bunch of ball bearings or BB pellets and swish them through them the tank with some muratic acid or the cleaner from POR-15.