Another newbie question. Just bought a 73 2.0 and took it to a local Porsche mechanic to check. All is well, but he says I need a new fuel tank, as it's full of rust. Enough to clog injectors, so mus tdo something. Porsche doesn't make them any more, but he knew of a place that 'rebuilds' them @ about $400.

Ouch! Ideas?

get a good used one. should be much cheaper than $400 bucks.

call the usual places, like EASY or HPH (there are more, just can't remember them all) ...

Andy

$75 to take your tank to a radiator shop and get it boiled and coated.

Do that. Splurge on a can of rustoleum satin-black to repaint the outside.

Replace the copper screen while you're in there.

Oh, and re-tap the holes for the expansion tank.

Personal comment: When I took my tank out, I got a full tea-cup size mound of rust powder out of it. Your's is probably that bad, but not worse.

G.

Thanks, guys.

I think POR-15 makes a kit for reconditioning, cleaning, and sealing the fuel tank. If it isn't too far gone. . .

Did the POR-15 dance... PITA getting the sealer out: the tank is just shaped wrong for this to be done easily...or my bench was

It's worth the $$$ to take it to a radiator shop.

Me again. Since I plan to race the beast, how about just putting in a fuel cell. New, supposed to be safer, and a bunch cheaper and won't rust. Drawbacks?

If you're tank was well rusted, it probably sat for a long time. Be sure to change the fuel filter and check the entire fuel system for leaks. Change any old or weathered fuel lines.

>$75 to take your tank to a radiator shop and get it boiled and coated.

Where? I called about 5 places in the San Jose area and the price ranged from $125 to $145. My tank is a little rusty but doesn't look too bad so I was just going to get it boiled and coated instead of replacing it.

How much do good used tanks go for? I assume these are probably fairly rust free but not coated. How much does the coating help anyways?

Also, I will be converting to AN fittings. I'll document they way I do it. My first plan was to modify a AN-6 adapter on my lathe so that it fits in like the original tube (after making the hole in the aluminum nut bigger). This would probably be a good way for someone that doesn't want to remove/refinish their tank.

Then I figured I would tap the tank with a 1/4-NPT tap. This should work pretty well and will give about a 0.300" opening that is close to the size of 3/8" hard line / AN-6 hose.

Now, since I have to refinish the tank anyway, I'll probably just fill it with water, then weld on a couple AN-6 or AN-8 fittings. Its been hard to find information on just what size fitting I should go with. It seems that the 3/8" hard line (and an AN-6 fitting) should work for up to about 400HP, but I assume it will handle more HP with a high pressure fuel injection pump mounted by the tank.

Jonathan

The $75 place is a radiator shop in San Mateo. Off of 3rd Avenue on the east side of 101.

The price may have gone up now that there's even more crud in "our" gas...

G.

I got a cheap fuel cell, $50.00 8 gal plastic drag cell with foam, but the fab work might cost more than the gas tank refurb and you loose your fuel gauge if its a street car...

>8 gal plastic drag cell with foam

Fab works no big deal. I'd do it myself. I don't even see why you'd have to lose the fuel guage. The cell in my 510 has one. The problem is I don't want to lose capacity.


Now, that I think about, since I've got a V8 and don't have a front trunk due to the radiator, maybe I should try to fit a cell in the combined front trunk (what's left after still allowing airflow for the radiator) / gas tank area. Of course I would have to reinforce the strut towers but that shouldn't be too tough.

Jonathan

think about it. the pump can't deliver any more fuel than it can get, and there's a limit to how fast you can suck a fluid through a hole.

but i agree AN-8 is more than adequate; if you have more than 400HP in your future you have so much fabrication work ahead of you that changing an AN-6 fitting to AN-8 will seem like child's play... if it's really likely, make your fitting AN-8 now and run an 8->6 adapter. 15 grams won't slow you down that much ...

My fuel tank developed a small leak and had rust at bottom portion from sitting for years. Used the Por 15 restoration kit (about $50) and it worked as advertised. If a used tank would have been available in my area, that would have been my choice.

BTW, I run a 400hp v8 and use the stock hose with electric pump in engine bay feeding a carb. No fuel starvation problems in the 16 months its been on road.

John

Howard,
As long as your tank doesn't leak,It can be cleaned and resealed.
I did the one in my 6r w/a kit from Eastwood for about $40.00.
Just follow the dir's,piece of cake.
Ron

> and there's a limit to how fast you can suck a fluid through a hole.

That's what I was thinking. I was planning on using a -8 line to the input of the fuel pump and -6 after that. My current engine is only ab out 300HP but my next will be about 450 or so.

the 8 gal should last for at least 3-4 laps!!!

I would like to see that AN conversion if someone does it. I currently have -6 hard lines to the back 90 elbows then steel braided flex lines to the F/I. I just have rubber pushed on the hard lines at the front. The pump is mounted by the big access hole on the outside with a filter in the tank area. Due to the barbed fittings on the pump I haven't decided how to run everything. It is currently all rubber hoses. I would like to go AN up front as well. I have welded used motorcycle tanks I used an inert gas filling it to avoid blowing up. I am not sure about this though as I have coated the tank already.

if you don't have a sanctioning body that requires all threaded fittings, what i'd do - especially on supply lines that see only gravity head and no significant pressure - is use a high-quality hose clamp - probably one of the Earl's (or equivalent) with the nice hose-end-looking shroud - and call it good. it will be.

especially since modern, oxygenate-bearing fuels do nitrile liners no great good, and you'll need to be thinking about replacing them every few years. (this sucks but it comes with the territory.)

I recently went through this same thing this summer. $90 at my local performance radiator dealer/repair shop (Everett WA, they seem to do most all the dip work for the area) When it came out, no rust inside and no paint outside. I didnt screw with coating the inside just keep it full and DRIVE it.

>When it came out, no rust inside and no paint outside.

The first place I talked to I asked if it would come repainted on the outside and they said that only the inside was affected so if the paint on the outside is OK (it is) I dont' have to worry about it.

>just keep it full and DRIVE it.

Those seem mutually exclusive.