Fuel Tanks, What to do Refurb or Replace?

[e21Keith]

Just got as far as preparing my fuel tanks for fitting. Amazingly out of 3 pairs they all need more than just a wire brush and repaint. They all have rust in the seams to some extent, one pair look like they could be salvageable.

Does anyone have experience of having tanks refurbished to a high standard? as I'd rather not have to buy new ones!

[Vic]

Have them sent for sand blasting and powder coated in satin black finish.

[uwbuurman]

Same here. Important thing is that they are rustfree on the inside.

[e21Keith]

It's not so much the inside that I'm concerned about, that all looks good. The seems along the front are all rusted, holed in a couple of places, so they need welding first and I'm not great at welding! The quote to have them done professionally is £660, or I can have new ones for just over £1000 from the dealer.

[uwbuurman]

Is there a leak? The seems around have a reasonable flange. In that flange it is common to have rust and holes, but the weld is still ok. Please place some pictures here, so we can help judging.

These are mine.

[e21Keith]

OK, here are some pics

[uwbuurman]

Thats quite the same as mine. Not leaking. Two options, just carefully open up the seem and have it sandblasted an powdercoated, afterwards fill the seems with some Dinitrol. Or have the holes welded, but stay away from the original weld, that holds the two halves together. But 650 is a laugh. Should be max 50 pound.

[e21Keith]

Some careful searching found these.

[uwbuurman]

Whow, almost brand new! But keep the old ones if you have the space, the are getting more and more sought after.

[e21Keith]

I just hope they are as good on the inside as outside, just waiting for delivery.

So I will have at least 2 pairs of not so good tanks for sale!

[Jeroen]

Well proper examples are really getting rare these days!

[e21Keith]

Saw these on eBay

https://www.ebay.co.uk/itm/Bmw-E21-323i ... 2508814522?

Made me laugh, none of the ones I have are that bad!

[e21Keith]

The replacement tanks arrived yesterday and the condition is as good as it looks both inside and out, so I'm really pleased!
I'll be dropping them off for powder coating later this week, it's been an expensive process due mainly to the shipping costs from the USA but still less than half the cost of new ones. I can't see that these tanks were from the 80's they look like much more recent replacements

[Jeroen]

Lucky you! Good ones are really getting rare!

[Atle_323i]

Where is the weakest point on the tanks? I can't fill up more than about 30 litre of fuel, before it starts to leak. So could it be the flange that leaks?
I haven't been under the car properly to investigate the issue yet. Any suggestions on where to look? The leak is coming from the right tank, where the filler tube is going in.