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Posted by: BahnBrenner914 Jul 2 2007, 10:06 PM

Took out the gas tank and it indeed is full of . I'll let the pics tell the rest:


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Posted by: BahnBrenner914 Jul 2 2007, 10:07 PM

The tank:


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Posted by: BahnBrenner914 Jul 2 2007, 10:08 PM

The gas from the bottom of the tank that didnt syphon out:


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Posted by: BahnBrenner914 Jul 2 2007, 10:09 PM

and inside the tank (if you have small children in the room, you'll want them to leave):


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Posted by: McMark Jul 2 2007, 10:31 PM

Yup, not surprised given the issues you've been having. And you've even got HOLES!

Time to go tank hunting.


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Posted by: BahnBrenner914 Jul 2 2007, 10:38 PM

Thats a reflection, not a hole. But it is chock full of rust. I rinsed it a couple times with alcohol, but theres still a good amount of gunk in there.

Posted by: McMark Jul 2 2007, 10:40 PM

Get a couple gallons of Muriatic Acid and CAREFULLY wash out the inside. Dilute the acid with water and use appropriate safety gear. We don't want you messing up yer face and losing your hot girlfriend.

Posted by: BahnBrenner914 Jul 2 2007, 10:56 PM

Check

Posted by: BahnBrenner914 Jul 2 2007, 11:08 PM

Also, my dad was talking about putting some ball bearings in there to break up the rust, is this kosher?

Posted by: Blood red 914-6gt Jul 2 2007, 11:12 PM

"Are you out of it boys? Everything is ball bearings these days."

I don't know what the ball bearings would do, but I have heard of a sealer to put in the tank that will coat everything to make it like new.

Posted by: BahnBrenner914 Jul 3 2007, 12:37 AM

The ball bearings would break off the rust that wont wash off with alcohol/acid/water so it's all clean when seal it, cause there's no point in sealing up rust.

Posted by: Danny_Ocean Jul 3 2007, 12:41 AM

The ball bearing trick may have worked on Dad's keen '59 Nash Rambler, but there are too many uneven surfaces/hiding places in our tanks for this method to remove all rust.

Have it professionally hot-tanked and pressure tested. Then seal with POR-15 tank sealer.

Do it right, do it once.

Posted by: GWN7 Jul 3 2007, 12:42 AM

The other option is take it to a rad shop and have them boil it clean.

Try the acid and ball bearings first and see how clean it comes.

Posted by: Gint Jul 3 2007, 12:54 AM

Here we go again...

Take it to a radiator shop and spend $35 to have it boiled, or otherwise tanked with a suitable alternative. If you have a shop with an ultrasonic tank you won' t believe how good it looks when it comes back. They know their business and you won't torch your digits with acid.

Posted by: rhodyguy Jul 3 2007, 01:54 AM

nice tanks will be fetching good money before you know it.

k

Posted by: Blood red 914-6gt Jul 3 2007, 02:02 AM

I hit myself everytime I think that I sold a very clean tank to Denny Acre for 50 bucks last year. I should have held on to it. All is well when helping a teener out though.

Posted by: 1bad914 Jul 3 2007, 05:51 AM

Take a short length ( 1 foot) of link chain and put it in the tank, then dance around your garage with the tank and chain. First off rinse the tank out, let it dry, then do the chain trick, do this for a awhile, dance and shake, beverage of choice, dance and shake, beverage of choice...you get it! Then rinse it out well and let it dry, then seal it with por-15 tank sealer. Mine is going on 5 years now and is working fine!

Posted by: type11969 Jul 3 2007, 07:52 AM

Did that with my Beetle tank 10 years ago and it is still spotless inside. I used the Eastwood kit though.

-Chris

Posted by: Phoenix914 Jul 3 2007, 08:23 AM

I also recommend using the chain method to clean up that gunk. Put it in the tank with some hot water and Castrol Super Clean or your favorite degreaser. Then use the POR-15 tank sealer. Better yet, buy the whole tank restoration kit - it comes with everything you need.

edit:

By the way, I just wanted to note that your fuel tank compartment looks pretty darn clean. Mine did not look that good...

Posted by: IanStott Jul 3 2007, 08:36 AM

I sent mine out to get professionally done and am very happy with the result, much better job than I could have done and no muss no fuss in my backyard! Tanks are very rare where I live and was mentioned above are only going to get harder to obtain, save yours if you can, you will be glad you did.

Ian Stott
Moncton
Canada

Posted by: BahnBrenner914 Jul 3 2007, 08:05 PM

Well I bought the muriatic acid and I've got a can of dad's old nuts , the uncoated, hardened steel ones. So I'm going to do my rattle nut dance (with the tank dry) and see how much that gets out, I like the chain idea too . Then I'll use the acid/water to rinse and get out all the crap and see what it looks like.

Another thing, what about the little strainer sock? Can I get another, do I need to clean it (non-buyable) or what?

Posted by: McMark Jul 3 2007, 08:19 PM

I've bought the sock at a bug shop before. But that was a couple years ago. Check availability before trashing.

Posted by: abbott295 Jul 3 2007, 09:24 PM

Excuse me for butting in here, but where does one obtain POR-15? I'm dealing with an off topic gas tank, and I tried looking for information on POR-15 here. but nothing came up on a search. I asked at one auto parts store and they were not familiar with it. And you pour this stuff in the tank and slosh it around and it seals the metal? Does it seal pin hole rust through too? Thanks for any information.

Posted by: McMark Jul 3 2007, 09:27 PM

http://www.por15.com

Posted by: abbott295 Jul 3 2007, 09:58 PM

Thank you, McMark. I will study that site.

Posted by: markb Jul 3 2007, 10:19 PM

Posted by: Danny_Ocean Jul 3 2007, 11:12 PM

Muriatic acid will burn you to the bone. It will blind you if even one drop gets in your eye(s). When you pour it on concrete (to remove oil stains), it causes the concrete to smoke.

I would seriously reconsider playing with this stuff.

And, if it does burn you, will you please post pics as a warning to others?

Regards,

D. Ocean

Posted by: BahnBrenner914 Jul 4 2007, 12:14 AM

well I didn't and I'm ok (i guess it was that chem lab last year that taught me not to mess with acid).

I put a bunch of nuts in there and did my dance and then I did a bath of diluted acid and then a water rinse and then another acid and another water rinse and then ran the shop-vac on blow to dry it all out and this is what it now looks like...


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Posted by: Mike914 Jul 4 2007, 12:22 AM

The stuff that comes with the POR-15 tank Seal Kit is Phosphoric Acid, quite dilute too. Also available as Ospho from Tru-Value Hardware on special order, 4 gal minimum... Not quite so dilute.

Also, the POR tank kit contains a de-greaser and the afore-mentioned Metal Ready etchant plus Silver POR-15 in a can labled Tank Sealer. Be sure and save the "sealer" and use it as you would POR-15. I got most of the pint back after coating my ghia tank a few years ago, most of the silver went on various 914's after that. Even one rusty silver '71 that was left in the rain after being primered, not a sealing primer either! POR-15 hates sunlight, so now the silver spots have turned a lovely greenish. I might get around to getting it painted someday.

Posted by: robby750 Jul 4 2007, 12:22 AM

Still looks like crap,

Posted by: BahnBrenner914 Jul 4 2007, 12:30 AM

So more acid or nut dancing or what?

Posted by: Danny_Ocean Jul 4 2007, 12:36 AM

You must remove ALL traces of rust. Any rust left behind will continue to "grow".

As mentioned before, take it to a shop.

Posted by: McMark Jul 4 2007, 12:49 AM

Let the acid sit in there for longer to get the stubborn bits. How long did you leave it in the first two times?

Posted by: BahnBrenner914 Jul 4 2007, 12:52 AM

I did a fair bit of sloshing, but it was in there like 10 min, you suggesting more an overnight type deal?

Posted by: Gint Jul 4 2007, 01:15 AM

Like I said, take it to a rad shop, pay the man $35-50, forget about all of the coating crap, paint/powder coat the exterior, fill it with gas and go for a drive.

Posted by: Danny_Ocean Jul 4 2007, 01:20 AM

Kids don't listen. They know everything. We all did the same sheet when we were young...screw adults. They don't know what they're talking about!

Then again, I didn't have access to free advice from the Internet in the '70's...

Let him shake, rattle & slosh. We'll be reading another post in a few months: Damn! Have to remove tank again!

Posted by: BahnBrenner914 Jul 4 2007, 01:33 AM

That would be a good title for another volume of my threads, but I'll check out getting it hot-dipped or cleaned tomorrow morning. So it's all bare metal when I get it back? and I just paint the outside and leave the inside bare and use it like that?

Posted by: Danny_Ocean Jul 4 2007, 01:38 AM

It will shine like a nickel in a goat's ass when you get it back.

You can leave it bare, but sealing will ensure a long time before having to re-do.

Posted by: bd1308 Jul 4 2007, 03:55 AM

now you went and done it!

Miles is gonna come back now!!!

RUn!!!

Posted by: Gint Jul 4 2007, 10:40 AM

Yup. Opinions differ on coating the inside of a fuel tank. You can coat the inside if you wish. I never will and I've done a couple of 30+ year old tanks. Just let the rad shop do their job and then take care of the outside and you're done.

Posted by: BahnBrenner914 Jul 4 2007, 11:18 AM

So the bare metal on the inside wont rust when I have it back in?

Posted by: rhodyguy Jul 4 2007, 11:59 AM

figure that's prob 30+years of neglect resting in the bottom of the tank. the build up takes time. the 'filter/sock' can be cleaned. reverse rinse with hot water, soak in some pbblaster, rinse again, repeat as ness. check the fuel outlet tube as the crap builds up in there too. both of these strainers were near plugged solid and sucked flat. look for the longer version if you can find one.

k


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Posted by: SirAndy Jul 4 2007, 01:23 PM

i coated my tank. after the acid cleaning routine ...
the stuff that i used for the coating was really thick. i *seems* to work OK, but i wouldn't do it again.

i would just clean it with the acid, wash it out, rinse with metal-ready/ospho and be done with it ...

no need for any extra coating.
Andy

Posted by: McMark Jul 4 2007, 01:27 PM

Watch out for reusing the sock. The flash aluminum washer/base is a sealing point. Use some fuel safe, non-drying sealant there or you will have a slow leak that will stink up the car as well as being mildly unsafe.

Posted by: por73914 Jul 4 2007, 02:18 PM

I once left a gallon of muriatic in a one car garage with the lid off for a couple of days. I had a Mercedes 450SL parked in there with it and the fumes totally destroyed all of the chrome on the car...bad stuff

Posted by: rhodyguy Jul 4 2007, 02:29 PM

think of what the fumes do to lung tissue if they'll eat a chrome finish. hyrochloric/muratic acid isn't a rookie product. you have to have the proper protective gear. if i did a tank at home i would further rinse the tank with a box of baking soda disolved in water mix to neutralize the acid. where do you guys pour the acid wash when you do this at home?

k

Posted by: BahnBrenner914 Jul 4 2007, 02:34 PM

Well I just got done with another acid bath (higher concentration) and left it in there for an hour or so, it's really cleaned up. I think in the next couple days (when I have time) I'll put in a similiarly high-concentration and fill the whole tank (not just the crap part) and let it sit for 2 or 3 hours , making sure to slosh it around once in a while to keep the burning going. I figure after that I'll have a spotless tank.

Posted by: por73914 Jul 4 2007, 02:38 PM

What do you do with the acid after you are done with it?

Posted by: BahnBrenner914 Jul 4 2007, 02:46 PM

I would tell you, but the Green Party will send swat after me

Posted by: rhodyguy Jul 4 2007, 03:20 PM

that would eventually be chambers creek, titlow beach, or day island. good work. please don't continue what ever it is you're doing, unless it is something related to the recycle center at the tacoma dump. did you grow up in the greater puget sound area?

k

Posted by: jk76.914 Jul 4 2007, 03:26 PM

I did the POR-15 route. Here's the before and after- (I've posted this before) I wasn't dealing with as much as you are. The POR treatment took care of the surface rust before the final sealing.

Posted by: Danny_Ocean Jul 4 2007, 04:02 PM

Can you provide more detail? Are you saying the base of the sock seals the inlet tube to the tank? What does/did the factory use to seal this?

(Sorry for the hijack, but I'm about to embark on the same project.

Posted by: ammason Jul 4 2007, 04:11 PM

I have to say that I'm a HUGE fan of the POR-15 system. My only advice is that you use nits/bits of iron or something ferromagnetic when you shake it around (or did you already do this? I might have missed it). The only reason is that when I treated an old tank I skipped over that part and used rocks and couldn't get them out after the thing had been cleaned.

The good part is that the sealant is strong and thick and it just made the rocks a permanent part of the inside of the gas tank.

I patched several holes that were more than 1/2" in diameter with JB-Weld after treating the inside of a tank, coated the inside, and then drove 5000 miles, before hitting a big rock (this was in the Caddy and the tank was exposed under the trunk of the car) and knocking another hole.

That stuff works fantastically - and if you're worried about bare metal, just make sure you use their whole system, including the finish coat - it's like rustoleum and will keep the rust from coming back...

Posted by: McMark Jul 5 2007, 02:01 AM

You've got it. Basically the base of the sock is a crush washer (single use). It deforms when you install it. So the factory didn't have to use sealant, and you don't either if you use a new one.

Posted by: Phoenix914 Jul 5 2007, 07:46 AM

Those strainer socks are readily available from the usual 914 parts suppliers.

Posted by: Bogaat Jul 5 2007, 10:58 AM

Now if I could only get my hand in the tank!

Posted by: McMark Jul 5 2007, 11:01 AM

It is installed from the outside.

Posted by: Bogaat Jul 5 2007, 11:05 AM

Hmmm, good thing I didn't force my hand in there to pull it off! Thanks

Posted by: rhodyguy Jul 5 2007, 11:06 AM

take off the capturing nut on the supply tube and the tube will pull out. the stainer will either come with it or you'll have to persuade it out. do not ruin the fiber gasket either.

k

Posted by: jk76.914 Jul 5 2007, 07:35 PM

Those are my pics. You're all welcome to them.

A couple of lessons learned by me-
regarding the flash rust (great term)- When I completed step 2, I rinsed it by putting a hose in one of the big holes on top. I let it spray with both tubes off at the bottom. The combination of running water and air flashed stripes of rust going down the inside of the tank, and I had to do step 2 all over again. The next time, I kept the bottom holes plugged, and rinsed by filling the tank full, then draining it quickly. I did it 3 times to flush it, and no rust. I'm guessing the lack of air slowed down the rust action.

after step 2, I put the vacuum hose from my shop vac into the filler hole on top, and put the end down to the deepest section of the tank. While it was sucking, I blew into the fuel level sender hole with my heat gun on medium. It worked great. I could feel the bottom of the tank heat up, and I could see the wetness disappearing when I peeked in around the heat gun with a flash light.

When I removed the tubes on the bottom and the sock, I munged up the thread on one of the nipples. It was a pain with magnifying glasses and jewelers files to clean it up, so be careful. Also, I learned that the nut is aluminum- very soft and easily damaged. I got new ones from Stoddard- they had to backorder from Germany but they came in about a week for only maybe $3 or so each.

This one will be controversial- To seal the tubes and the sock, I installed them while the POR-15 sealant was still wet. It's now TOTALLY permanent, but I didn't want to fool around with leaks, and, after 98000 miles and 30 years, my sock was still OK (replaced it anyway), so what the heck.

Good luck!
Jim

Posted by: rhodyguy Jul 5 2007, 08:06 PM

nice write up jim. how i dried my tank after draining the water...on the bench top with a elec space heater pointed at the fill/sender holes. warmed the whole surface of the tank in about 30 minutes. bone dry in an hour. this worked well for a bit of warmth to the tank prior to ext painting.

k

Posted by: rjames Jul 5 2007, 09:24 PM

A hair dryer in the filler hole worked for me. About 30 min and the tank was dry.

Use new washers and it shouldn't leak when you fill it up again.

Posted by: BahnBrenner914 Jul 9 2007, 07:41 PM

Well I just finished the last of my acid with the tank completely full and got all the rust out. I put it in the sun with the shopvac on blow and the tank upside down on some sawhorses and dried it out in less than a half hour, but it instantly flash-rusted.

So is that normal? (asking the non-sealer guys, considering the rest of you are crazy about cleaning and sealing it with the kit).

Posted by: John Jul 9 2007, 09:25 PM

I would follow up the acid treatment with a Phosphoric Acid treatment.

This will leave a coating of Iron Phosphate on the inside exposed metal surfaces and will help to reduce the risk of flash rust.

I am a proponent of coating the inside of the tank, so after phosphatizing the tank, I would coat it.

Posted by: Gint Jul 9 2007, 09:29 PM

In Florida it is... Your shop vac is just blowing wet air.

Colorado is drier than a popcorn fart. Once again, I pick mine up from the rad shop, paint the exterior and toss it in the car and fill it with gas and go.

Posted by: BahnBrenner914 Jul 9 2007, 10:31 PM

Doesnt the coating kit come with phosphoric acid as the cleaner? I'm starting to lean towards coating the tank considering it isnt exactly driven around all the time.

Posted by: BahnBrenner914 Jul 10 2007, 08:17 PM

I went and got a new strainer sock for the tank...




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Posted by: BahnBrenner914 Jul 15 2007, 11:26 PM

So the tank is all cleaned out and I installed new hose under the tank:

Posted by: BahnBrenner914 Jul 15 2007, 11:28 PM

Then installed tank, fuel gauge, expansion chamber...




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Posted by: McMark Jul 15 2007, 11:53 PM

You may have the hoses get kinked after the first drive. You'll notice when the car dies.

If that happens, safely raise the front of the car, and remove the lower cover, then pull the hoses out of the access hole and carefully reinsert them making sure they don't kink.

Good luck! I think you're close!

Posted by: BahnBrenner914 Jul 16 2007, 02:00 AM

I made sure all that extra hose was looped, not kinked, so hopefully we dont have that problem.

Posted by: boxstr Jul 16 2007, 09:59 AM

I would hold off on filling the tank to the top. Fill part way then start the car and drive for a short distance then, If everything is tight and no leaks, fill the tank.
One thing I like to do when the tank is out, is move the pump and fuel filter to the side of the front trunk area, on th eearly 914s even on a 75-76 914. That way if you have to change the filter. You do not have to jack the car up. Trust that the jack stands will hold and slide under the car, loosen the hose clamps, gas dripping down, remove the old filter and gas dripping down, install the new filter and tighten the clamps.
You can mount everything in a secure and safe place.
CCLIN914NATION

Posted by: Bogaat Jul 16 2007, 10:25 AM

So is the best place to mount the pump/filter under the tank in the cavity? Mine is currently underneath the car behind the "skid" plate rather than in the confines of the gas tank body cavity. It had previously been relocated. It seems it would be easier to get to from underneath when replacing?

Posted by: boxstr Jul 16 2007, 10:56 AM

The early 914s 70-74 had the pump and filter mounted at the midsection passenger side, near the heater tubes. Good place to casue vapor lock and heated fule problems.
The 75-76 pumps and filter were mounted as you see in teh previous pics, under the tank and the pump secured to a small access cover that you pull out, through, and into the front trunk area.
This is the better of the factory locations, IMHO.
But, if you have the tank completely out, I prefer to move the pump and filter into the side wall area in the front trunk.
I will try and post a pic.
CCLIN914NATION

Posted by: BahnBrenner914 Jul 16 2007, 01:25 PM

Definately. I have the gear stack out right now, so I'm not putting anything in there yet. I'll probably put a gallon or two in of regular (see my poll/thread about gas grades) and see how that runs and adjust accordingly.

Posted by: Brian Mifsud Oct 10 2007, 02:59 PM

If you are concerned about "Muriatic" (Hydrochloric) Acid,... just go down to the supermarket and buy a couple gallons of white vinegar. It will work more slowly, but the acid WILL still dissolve the rust.

Nuts and Bolts, shake it repeatly.

NEUTRALIZE the acid with BAKING SODA!.
Rinsing with water will not neutralize the acid and it is heavier than gasoline, so will stay in the bottom of your tank, eating steel.

Posted by: Cevan Oct 10 2007, 03:10 PM

Now you prepare that Fetzer valve with some 3-in-1 oil and some gauze pads. And I'm gonna need 'bout ten quarts of anti-freeze, preferably Prestone. No, no make that Quaker State.