Fuel tank replacement?

[rpjg_1975]

Taking the car on a 500 mile round trip this weekend so went to garage to brim fill it only to find a pool of petrol on the floor!!! After popping up to the garage they advised that it is probably a rotton top to the tank. Anyone know any decent places to get one and if it's a garage job to fit or is it 'diy' able??

 

[poprock]

I take it yours is an older, square-dash car then? Those had the steel fuel tank, which was replaced with a plastic one for the oval-dash models.

Porsch-apart do a grand job of resin-coating the inside of the old steel tanks to make them airtight and better than new. They also buy back your old leaky one so that they can treat that and sell it on to the next customer.

 

[Paul Fraser]

A cheaper option (what I did) was get a tank off of Ebay for about £75 delivered and then I cleaned/treated it with tank cleaner/sealer from Frost, another £35 or so. You'll need to drop the diff to replace the tank as well as dismantle the area around the filler pipe -- I used my uncle's pit and it took me a few days on and off to do. The plastic tank won't fit into the older cars unless you cut half the differential support beam away and work out how you are going to reinforce it.
PS They usually rust at the corners under the metal straps that support the tank (and catch moisture/dirt).
PPS Just had a look at your post again. If yours is a '86 oval dash it is more likely to be the fuel lines as you have the plastic tank. A decent garage should be able to cut out the rusted pipe and replace for not much money (I was £20 but that was at very cheap Shetland labour rates of about £20 an hour).

 

[rpjg_1975]

Are the pipes at the top of the tank then? I only ask as I have never had this problem before until I filled it right up last nite. I think that's why the garage presumed it was a metal tank and rotted at the top? Is there any other possibilities, i.e seal between filler neck and tank? I guess the only way to find out would be to get the tank dropped down?

 

[swright]

This hapened on my old 84 lux a number of years ago. In my case it was the seam around the tank. Oh and the fuel lines. I replaced the fuel lines with high pressure rubber fuel hose and simply never filled the tank up[]

Like a fool i first tried normal fuel hose but they quickly split from the pressure( i was young and didnt know a lot back then!!)

 

[Paul Fraser]

First I'd have a quick look under the back and see if you have a plastic or metal tank. You don't need to raise the car to do this and it will be quite obvious.
Sorry about wittering on about fuel lines above, just reread your post and saw it only happened when you brimmed it.

 

[rpjg_1975]

Have just been outside.... in the rain (just for a change). Looks very much like it is a plastic tank which I presume would put the fault down to the filler neck joint or something?

 

[Paul Fraser]

Sounds like it, or the fuel probe sensor. You should be able to get access to both from inside the boot but it is quite time consuming to take the metal shield around the filler pipe apart as it is sealed with very sticky sealant all around. I eventually resorted to brute force/claw hammer under the shield at the bottom of it to rip it off. The fuel probe is covered by a circular plate.
I still don't see why either of these should cause a problem really; still think it would be worth getting underneath, cleaning and drying and then refill carefully and slowly to try and pinpoint where the leak is coming from.

 

[rpjg_1975]

I will have to investigate that once I get back then. Maybe the rain will stop for a while to help me out!!!

 

[rpjg_1975]

Fuel update!!!

Doing some investigation and opened the rubber cover to look at presumably the fuel probe and in the 'dish' at the top was some fuel. I turned what I believe to be the large plastic nut that holds the whole thing in and managed to get a few turns on it so I wonder if this has been my problem? I will have to uncover it when I fill up again and see if any appears there again []

 

[Paul Fraser]

Glad you found something likely; hope tightening it sorts your problem out.

 

[rpjg_1975]

Keeping my fingers crossed. Drove into town with sunroof and windows open and didn't have any noticable fuel smells so better than before. Could well be that it has been the cause of my fuel smells since I bought the car. Will keep updated once I fill the car up again at the weekend. Will also work out my fuel consumption over the 500 odd miles []

 

[Paul Fraser]

Might be worth popping the rubber cover off and having a look as you do the refuel... If it isn't that but the filler I suppose there is a chance that the petrol could run over the top of the tank and pool in the fuel sensor recess if the car was angled correctly.

 

[rpjg_1975]

Did exactly that. When I topped it up this morning I had a couple of bubbles from the centre of the nut, so I tightened it a little more, and when I refilled after half the journey tonight (260 miles) I didn't have anything so looks like problem solved...

Incidentally how's this for fuel economy?? 260 miles done, refilled to brim tank, 31 litres. MPG 38 I believe? That was on a steady 70-75 all the way []

 

[Paul Fraser]

Glad you got it sorted and v.good mileage.