Fuel Tank leak?

iandecjak

Club Member
Last weekend I decided to fill up rather than splash £30 in which usually lasts for a few trips......parked up in the pub and when I came out there was obviously a leak from the tank. At first I thought it may be connected to a replaced fuel pump and pipe clips working loose which they have in the past but not so simple and the leak is from the tanks seam by the filler pipe as best I can tell.
I have taken off the inspection cover in the boot and that look dry as does the filler pipe.
It looks like the seam is leaking - is that to be expected or is there another pipe that can't be seen from the inspection cover.

If I have to get a new tank god knows where from - any suggestions or advice?
 

iandecjak

Club Member
Cheers Huw this could be a good option - will have to get the tank off and have a looksee at what the issue is - ah well.........
 

Jimbo

1978 260z in yellow
Club Member
speak to readyrads in brum they did mine.
they cut the tank in half, ahot blast and weld up any holes then seam weld it back together and paint it.
it aint cheap but its a very good permenant fix.
 

iandecjak

Club Member
Jimbo thanks this is something I haven't even considered - what sort of price did they charge if you dont mind me asking?
 

Jimbo

1978 260z in yellow
Club Member
i paid £150 which sounds a lot but i dougbt you will find a good tank for that money.
they ended up welding most of the top part of the tank opposite the filler pipe.
they also took before and after pictures too as one of the things i wanted to know was which way round the pickup and return pipes are.
my uncle in all his wisdom had connected them the wrong way around before i owned the car and it would "run out of petrol" with a quarter tank still showing on the gauge lol
 

iandecjak

Club Member
Doesn't sound too bad if you end up with a refurb tank - an exchange one from the US is going to be twice that and the gunk Huw mentions is £80.......I may shop around nearer home and see if there is a local option. Thanks for the response it was really helpful.
 

Jimbo

1978 260z in yellow
Club Member
heres some pics of the finished result.
you can see the large bits they cut out and replaced.
never had a leak since.

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Loiner240

Club Member
I had a similar problem with my 240Z - filling up and finding a leak in the tank. The petrol was seeping through the seams of the tank. I had the tank removed, repaired and pressure tested. Cost about £180 in total. This was in W Yorks but I'm sure there would be places closer to you that could do similar work.
 

iandecjak

Club Member
Yes thanks Paul I found them online yesterday and have fired in a request for info so hopefully will know more next week........not looking forward to getting the old one out though....
 

johnymd

Club Member
As I see it, one of the big problems with old tanks is that they lose their protective coating so once they start to rust, it quickly gets worse.

With regard to refurbishing a tank. When do they coat the inside with to prevent it rusting quickly? Ideally you would want the whole tank re-galvanised before you start putting fuel back in it and that can be expensive.
 

iandecjak

Club Member
I finally jumped into removing the leaking fuel tank; which all in all didn't go so bad over the last two weeks.
Access to the sender and pipe work through the boot works well and all the old pipes disconnected without too many swear words also the main fill hose also removed ok. The same could not be said for the tank strap brackets which needed a deep (80mm) 14mm socket to be ordered as room for spanners is a bit restricted.
Using a jack I started to lower the tank only to find a not previously mentioned vent pipe just to one side of the sender unit which was not visible or mentioned in any of the manuals.
Anyway with tank off and sender unit removed I could see inside the tank which looked brand new; the leak traced when flushing with water to a number of pin holes along the top of the wide joint flange on the filler side.
I took the tank to Arrow Rads at Avonmouth, where Phil was very helpful and within a couple of days had patched, as well as silver soldered the affected area, pressure tested and painted for £158 inc VAT.
So today I refitted the tank with new pipework/jubilee clips all round (not the large fill pipe which was fine) along with new rubber strips on top and along the straps; the only problem being with the larger vent pipe which goes through an oval sleeve in the inside rear wing with the replacement 25mm OD pipe being a bit snug.
Refilled and took the car for a 40 minute shake down with no leaks or other issues.......so thanks to all who offered advice it was very much appreciated and in the end what could have been a pig of a job as I said didn't go so bad.....
 

Jimbo

1978 260z in yellow
Club Member
As I see it, one of the big problems with old tanks is that they lose their protective coating so once they start to rust, it quickly gets worse.

With regard to refurbishing a tank. When do they coat the inside with to prevent it rusting quickly? Ideally you would want the whole tank re-galvanised before you start putting fuel back in it and that can be expensive.
you dont really want to coat the inside as it can contaminate the fuel if it comes away from the steel which is then a real pain in the bum to get back out.
all it needs after the work is a litre of fuel mixed with 2 stroke oil to give it a swill which will protect it short term.
i fitted mine back in the car the next day so didnt really have a problem.
the refurb cost wasnt a huge amount of money compared to trying to get another origenal tank but if i was really serious about not havin ga rusty tank again i would go custom alloy tank.
theres plenty of fabricator places out there that could make one using the old tank as a template.
 
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