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Rogviler 12-25-2016 04:02 PM

1984 4kq: Resurrection
Well, due to some recent changes, I was forced to get this car registered again, so since I'm down to only three projects I can give it some attention.

Is anyone still out there? I don't know, but since I'm going to be having to do some mojo to get this car going I figured I might as well document it. It's been sitting for about four years or so. The only reason it was parked is because the back doors don't open and I needed something to load kids into. At that time they still needed help getting buckled into carseats.

Once I put a battery in it and borrowed the fuel pump from my Fox (Audi) it fired right up, but wouldn't rev much. I managed to get it moved by flooring it.

And then I found out why...

Here's the gas that came out of the tank:

No, that's not a dirty old oil pan, it was sparking clean.

Then I removed the tank...

Look at how much trunk space we could have! I briefly fantasized about having a custom tank made that would fit between the frame rails and down into a hole behind the diff. Then I snapped out of it. Maybe someday when I get a garage and a TIG welder.

I did one round of toilet bowl cleaner in the tank, but unfortunately didn't get a pic. Tons and tons of rust flakes and brown liquid came out. I'm going to do another once it clears up a bit outside.

Here's where she sits...

Aside from more tank cleaning, I'm also going to be reviving as many of the three seized fuel pumps I have as I can. Two were brand-new Bosch pumps and one looks to be an Airtex that will be good to keep in the trunk if I can get it unstuck. I'm making a rig to do this, and if it works I'll document that. I don't know if they're stuck because of gummy gas or (more likely) rust from water settling right down into them. Good ole ethanol. If I can't get one of them going I'll probably cut it open.

Stay tuned.


Rogviler 12-27-2016 12:13 AM

Got started on my art project...

:D Most of this fuel pump rig is stuff I had lying around, so at the very least it'll be cheap. I only bought the switch and a junction box that will hold all the wiring. See if you can guess what's what as I go along.


Rogviler 12-27-2016 02:59 PM

More colorful...

I feel like I should paint the board something crazy. Pink?? The kids already decorated it at some point with a bat, so at least that's something. Actually I do think I have some purple latex paint somewhere...

All right, I'm sure nobody's in a playing mood, so I'll explain what everything is. (Thank the maker there's only a few days left of this miserable year!)

The two bolts are for hooking up either a car battery or charger to provide power. Inside the box is a 30A circuit breaker I scavenged from a Power Wheels car, just in case. The switch has three positions and six terminals. I wired it so that the middle is off, one side runs the pump forward, and the other side runs it backward. That's the best way to get a pump unstuck-- rock the impeller/armature back and forth with some kind of penetrating fluid inside.

You can see here what they look like inside and how much surface area there is to get glued in place:

So that's pretty much it. The yellow things are some kind of contraptions for buttering corn. I'll drill some holes in them so I can ziptie the pump down. I also have a tank that I might add at some point that would allow for fluid to be flushed through the pumps. But for now, we'll see how it goes.


Rogviler 12-28-2016 10:05 AM

Well, she works...

The Airtex and one of the Bosch pumps freed up after a few minutes of back-and-forth plus some tapping on the ends with a rubber mallet. The last Bosch pump has not yet come back to life. It clunks in both directions, but that's it so far. I'll keep working on it.

Yeah, we started painting it purple. Turns out this operation gets pretty messy, and the acetone/ATF mixture I'm using is just going to take the paint off so it may have to stay bare wood.

Also, my fancy charger won't work for this, which I figured. For now I'm using a battery, but I'll dig out my rusty old metal charger that my dad had. No fancy circuits to overthink things.

Lastly, I used ring terminals, but I'm definitely going to switch to alligator clips. Also thinking of attaching one of the "free with coupon" Harbor Freight multimeters.

Wish me luck with the last one...


Rogviler 12-30-2016 02:49 PM

I think the tank is finally as clean as it's going to get. The first round I used The Works toilet bowl cleaner, while this time I decided to try this since it was half the price and specifically says it works on rust (seemed no better or worse though):

Seemed the same. The ingredient that works on rust is hydrochloric acid (AKA muriatic acid), which almost all toilet bowl cleaners have (or hydrogen chloride, which reacts with moisture into hydrochloric acid), so that's not surprising. My only tip is to not buy the kind that's simply bleach (sodium hypochlorite) because that will just cause rust.

It's important to know that you'll never be able to get a shiny inside and have it stay that way. But those worked really well to dislodge the big flakes that were causing problems. Also, these tanks have no way to effectively drain them, since all of the openings have a lip on the inside. I elected to drill a hole in one of the top corners, which made it much easier. I'm just trying to decide if I want to put in a removable plug of some sort or just seal it back up.

Also, when you're done flushing it out with water, definitely slosh something oily around in it and then drain again. Some things you could use would be diesel, some ATF or clean motor oil mixed with acetone or mineral spirits, or WD40 if you have a jug of it. All of those will be fine to leave a film of until you can fill the tank again. The car won't even notice.


Rogviler 01-01-2017 03:41 PM

Something I found out today: If someone buys a cut-to-order hose from a parts store and then returns it, they'll throw it in a box and give it away for free or cheap. It's usually short pieces, but in my case I got enough to replace the hoses from the tank to the return line and to the fuel pump for free. BTW, it's 1/2" for the fuel pump and 5/16" for the return.

Looking forward to the kids going back to school this week so I can work on it some more.


Coupester 01-03-2017 07:12 PM

Hey this stuff...please, keep posting up sure there more of us out there...and more pictures please ! 😉👍

Rogviler 02-04-2017 09:28 AM


The weather has finally stabilized a bit so I've been wrestling the tank back in. The part that sucks is the rubber grommet that the two tubes from the tank go through in the floor. And also four vacuum lines. You can either put the grommet in first and then struggle to line it up with the gas tank tubes or install it on the gas tank and then struggle to get the vacuum lines through and then get it sealed properly in the hole. So far no luck with that, I'm going to have to see if anyone has posted any tips. I hope so, lots of people have had to take their tanks out and clean them.

Also, Google is almost useless these days for stuff like this. You try to look up something car-related and you get pages of places selling parts. Then when you finally get to actual results you realize that Google has excluded most of the words that you were searching for. How is that helpful? Putting them in quotes no longer works like it did, nor does adding + in front of words. Grr.


Rogviler 02-04-2017 09:42 AM

Good article I found on the tank, though no luck on the grommet yet: Forums: Fuel tank repair (pics to follow)

Makes me wonder if I should just do the same while I have it out.


Rogviler 03-24-2017 09:26 AM

$#@% that rubber grommet. For now I reinstalled everything and just left it loose.

I thought I had a blockage in the fuel supply line, but it turned out that the Airtex, while it works, is not strong enough to actually pump fuel. So I'm on the working Bosch and so far it's doing great.

However, I've still got the no-rev issue:

Which is almost certainly gummy goo in the fuel distributor (dealt with this before), so I'll have to grab some carb cleaner which seems to be the only thing that will cut through it.

Ah well, at least I know there's no crap in the tank to clog things up now.


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