E30 Zone

Hi,

Please can you help me?

I have a 318is and have just spotted fuel dripping from the bottom of the fuel tank. I'd noticed the smell before but had assumed that it was something to do with the perished rubber around the filler (or something).

1. is it possible to patch it with something whilst I find a replacement?

2. ECP have a tank for £196.80 Is that a fair price / the best place to go?

3. I'm not much cop with a spanner...any idea how much fitting a new one will cost?

Thanks very much!

1. I'd find a replacement rather than patch it up.
2. God they've gone up since I last brought one, personally I'd look for a good second hand one - around £40-60 for a good one.
3. Changing a tank involves removing the exhaust system & prop so isn't a quick job, where abouts are you in the country as there are zoners dotted about all over that will do this at a better rate than a garage.

HTH

Charlie

Have you found the suspected hole or are you assuming? As you say you found it dripping... Can you see where its coming from? I would check the hoses going to the fuel pump before replacing the tank or atleast find the fault. You may find its a loose connection or a aged hose... Does it drip all the time too orjust after drives?

Hey Charlie,

Thanks for your reply. I'm near High Wycombe. Bit wary of a 2nd hand tank...might need doing again before long, and as you say, the job isn't a quick one.

I intend to replace it asap, but wondered if I could make it safer in the short term?

As the job entails taking the car apart, is there anything else that I could fix during the process? I think my rear top mounts are on their way out, and have always wanted to do the bushes. In for a penny...

Hi Jim,

Well it was dark & cold so I didn't get a chance to have a proper look.
I had noticed that the petrol smell was stronger after filling the car, so have kept it 1/2 full for a while. The thing is, it was parked for a good 10 hours and a small puddle had formed underneath. The car was parked on the flat, and The drip looked like it was coming from the middle of the tank.

I'd personally give it a proper inspection just to rule out anything else, the worst outcome is you find a rust hole and you need to replace you take... The best outcome is a loose connection... Your probably right to assume there is a hole though!

yep, you're right of course. Will just have to wing it until the weekend and hope that no-one throws a cig butt nearby...

Cheers,

Simon

£190 is a fair price, I recently priced up. You can get a replacement from Germany for £130, but you have to add post and a two week wait. My local factor does them for £190, and that was within a few quid of the cheapest UK online I could get.

I wouldn't bother with a SH one either. I have to do the same as you, I thought I had fixed it with a new rubber pipe (so did mr MOT man). but when I put £25 in I was in the kiosk waiting to pay and looked out the window and saw fuel running out from under the car. Normally it is only a drip for a few minutes after I stop driving.

I am just gonna drop the tank to have a look, and replace or repair as necessary, I suggest you do the same. I am not gonna order a tank until I get the old one out though.

Will get it booked in somewhere for an inspection tomorrow. Let me know how you get on with your tank...good luck!

It probably is the tank that is dead, if it isn't that its your filler pipe but more likely the tank from what you described.

Some key things to remember:

1. check what size tank you have there are 2 types!
2. 2nd hand ones can be fine, mine was £45 really good nick
3. If you buy 2nd hand, paint it in hammerite for that extra bit of protection
4. You can get it fitted between £70-£80 if you shop around

Couldn't believe I got quoted £250 for fitting by a garage that "owed me a favour"!!! Decided i could be bothered to do it myself anyway, get the underseal out while I am under there!

I had to get to grips with the whole tank size thing. Pop your rear seat up and look under the inspection plates (they just unscrew) Mine has a sender each end, so has two hatches. I don't know if a single hole tank still has the two hatches under the seat or not, but thats the main thing. Also get the right size of the two or your level will read wrong.

The tanks tend to fail at the filler pipe,there's a stub pipe welded to the rear upper r/h side,or from the seam at the top of the tank.

Before buying a tank,it is well worthwhile having a look under the car just forward of the rear o/s wheel,you will see a rubber pipe joining the filler pipe to the tank.Give this pipe a firm tug,if you see the stub into the tank move,the tank is goosed,but a zoner reported recently that the rubber pipe on his car had split,a nice easy and almost cheap fix!

Bear in mind when ordering a tank that there are two sizes,a 'like for like' swap is very much easier than changing capacity!

If doing a tank swap yourself on the driveway,allow half a day.

Worth looking VERY closely at the rear brake pipework in the area of the three way connection whilst the tank is out....

It was me that had a pipe go, unfortunately, after fitting the pipe, it still leaked. Going to have to drop it to look, the filler pipe had only surface rust and was completely solid underneath. My suspicion is the seam above the filler as the leak runs directly from the filler pipe which is right next to the seam. oh well, we'll soon know! probably gonna drop it tomorrow if it's dry.

Snag is,the tank can look perfectly sound,but the seam that holds the top of the tank on can develop pinholes,as can the join around that stubpipe.

Petrol is very sneaky stuff,can leak through the smallest of holes.

Given the cost of even a pattern tank these days it's very tempting to have a go at welding a repair patch in,please do not,the fumes hang around for ages and petrol will 'flash over' at remarkably low temperatures....

Well, if it does look repairable, I won't be welding it unless it's completely full of water (with the hole at the top obviously) But, the most likely is a nice shiny new one, the old girl deserves it!

Id rather repair a BMW tank than fit a GSF/Euro one, had bad experiences with fuel starvation on my 63 litre GSF tank

Somebody needs to get pics up of one of these German tanks, might get a look at one soon so will see how good they are

My experience of German remanufactured parts is good, I got a whole twin exhaust from cat back for about £30 and it's well solid, and extremely similar to the oem one. That was from an ebay company called Eternal Cars.

The only way I will weld a tank is to fill it with water then set light to it. You wont get all the fumes out by filling with water but it reduces the amount of air in the tank so what petrol is in the tank will burn slowly due to being starved of air . Also don't think that when it's gone out it's safe , I put a blowtorch in several times to make sure and again when I half empty the tank and again when fully empty.It's much safer this way as you are controlling the burn slowly rather than hitting it with a welding torch and super heating the fumes with very dangerous results . This method has worked for me on several different types of tanks and the 65L is nice and easy with the two big holes in the top .
Sometimes you can't see it's burning but if you feel the top of the tank and it's warm then there is still petrol in there .
Another problem I have found on what I think is non genuine second hand tanks is the small breather pipe that is brazed across the top of the tank rusts through where it is brazed . This pipe is part of the tank and is not available so my tank now has a piece of pipe from a scrap mondeo fitted .

I haven't welded a tank before, but don't worry I know how bad they are. I would not even attempt it without sealing up all the holes and having it full to the top. If I turn it so the bit I weld is at the top, with a 1/2" air gap under it before water-well, as far as I understand, if there's no gas, there can't be a bang? I have heard the metal itself holds petrol so even if you wash it out, it will still have vapour coming off it!

DanThe wrote:Id rather repair a BMW tank than fit a GSF/Euro one, had bad experiences with fuel starvation on my 63 litre GSF tank

Somebody needs to get pics up of one of these German tanks, might get a look at one soon so will see how good they are

Coated in Hammerite metal paint I'm sure they ain't too bad!

And there is NO WAY I would attempt to weld an old petrol tank!

I started to weld / braze tanks years ago when a popular engine swap was the ford 2.8i into cortinas and even my own transit . They run an external fuel pump which doesn't self prime so the pipe and swirl pot has to be cut out of the donor tank and welded into the tank . The method I described above has never caused an issue for me and I have never had a problem .

So, I had the tank checked out at the local garage. It's not leaking from the bottom, so they think it's either a small hole where the filler tube connects to the tank, or a corroded seam.
The leak appears to have stopped for now, so I guess it's just a case of keeping the tank no more than half full and keeping an eye on it until I can find someone to help me fix it who isn't going to charge me £560 - £600 (what the last two quotes were!)

Thanks for your help,
Simon

Some leaks at the filler stub can be cured by ensuring that the rubber hose is pushed up as close to the tank as it will go, and that the hose clip is as close to the end of the pipe as possible.
Not likely if the fuel is dripping from the back of the tank rather than the front, but two other causes of fuel leaks on an E30 tank are a split O ring seal for the fuel pump and a split main vent hose where it goes onto the tank. Both can be checked by looking under the RH inspection cover under the rear seat cushion.

My touring had exactly the same leak, it seaps from the seam and is not obvious where it's coming from at first. I just fitted a Euro Car Parts tank as a real one is £500. Tank was good quality and went straight in with no fitment issues.

I would do the same even if it is the filler

Well, got the new tank today and got it fitted. Extremely pleased with the tank, it was an excellent fit, nicely painted in hammerite silver, so it should last for a while.

I took my time, wanted to make sure everything else was checked out while I was under there, and made sure it all went back together properly. I fitted new gearbox mounts as they were completely mashed, a new prop centre bearing as the rubber shield was only attached for about 1/2" of the circumference! new fuel filter etc. I am glad I have done the job myself really, as I have been wondering where the slight vibration through the seat base was coming from, and I reckon I will have cured it now.

Definitely recommend it as a job you can do yourself, the main thing is getting the car high enough as you need access to the whole underneath, as you need to drop the front half of the exhaust down a bit for access. ( I just loosened the manifold join so it would move to one side) and I got the nice feeling of knowing it's all done right!

Good news is the old girl is very solid underneath, first time I have ever really got to grips with down there! I like the fact the heat shield is Ali, I guess that's the difference between a cheap car and a bmw.

All I need to do now is replace the crappy jubilee clips I bought for the job with some better ones, I got a slight leak if you pull on the fuel filter as they are the type that will only do up so far, and they won't quite clamp properly.

Matt

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 459wt_1139

This is where I got the tank from in the end, excellent price!