welding petrol tank

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brixtonmorris
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Re: welding petrol tank

Post by brixtonmorris »

Maybe it is true Stephen that the original that were better quality, but your tank has past its sell by date.
It's no longer as good as the original.
myoldjalopy
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Re: welding petrol tank

Post by myoldjalopy »

If the tank is rusty there is the danger of bits of rust clogging up the fuel line. That happened to me once and blowing back down the pipe to tank got me on my way again. But I was wary that it could happen again so I upgraded from a 5 gallon tank to a 6.5 gallon one and killed two birds with one stone 8) But if anyone else is thinking about doing this, beware the new, bigger tank will require shortening of the metal filler pipe and the 1000 model spare wheel clamp to replace the smaller SII one.
Anyway, my "new" tank (now about 20 years old) is holding up fine.....so they can't be that bad.
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svenedin
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Re: welding petrol tank

Post by svenedin »

brixtonmorris wrote: Wed Dec 31, 2025 2:46 am Maybe it is true Stephen that the original that were better quality, but your tank has past its sell by date.
It's no longer as good as the original.
It's not my tank. My fuel tank was new a few years ago. That's how I know about the different types of new tank.

My tank was riddled with holes and had blocked the fuel line with internal rust. It was so bad there was absolutely no point in even thinking about repairing it.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
stuffedpike20
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Re: welding petrol tank

Post by stuffedpike20 »

Another update.
I bought a new tank for £276, which is a LOT of money to me, being unemployed.
The new tank has instructions to swill out with petrol before fitting, and there is a smell of waxoyl inside.
However, there are patches of rust to be seen inside the tank. I am going to inform the seller.

To sum up...I could only get a large capacity tank, which I did not need or want. The new tanks are not as good as originals. Mine already has rust.
£276 is a lot of money to some people.

Moderate your attitude brix.
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svenedin
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Re: welding petrol tank

Post by svenedin »

stuffedpike20 wrote: Wed Dec 31, 2025 1:35 pm Another update.
I bought a new tank for £276, which is a LOT of money to me, being unemployed.
The new tank has instructions to swill out with petrol before fitting, and there is a smell of waxoyl inside.
However, there are patches of rust to be seen inside the tank. I am going to inform the seller.

To sum up...I could only get a large capacity tank, which I did not need or want. The new tanks are not as good as originals. Mine already has rust.
£276 is a lot of money to some people.

Moderate your attitude brix.
I would add that my tank, new 3 years ago has rusted on the exterior where the very poor paint has literally fallen off. In addition, for about 6 months after fitting I found fine red particles in the float bowl. I assumed it was paint.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
stuffedpike20
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Re: welding petrol tank

Post by stuffedpike20 »

svenedin wrote: Wed Dec 31, 2025 2:33 pm
stuffedpike20 wrote: Wed Dec 31, 2025 1:35 pm Another update.
I bought a new tank for £276, which is a LOT of money to me, being unemployed.
The new tank has instructions to swill out with petrol before fitting, and there is a smell of waxoyl inside.
However, there are patches of rust to be seen inside the tank. I am going to inform the seller.

To sum up...I could only get a large capacity tank, which I did not need or want. The new tanks are not as good as originals. Mine already has rust.
£276 is a lot of money to some people.

Moderate your attitude brix.
I would add that my tank, new 3 years ago has rusted on the exterior where the very poor paint has literally fallen off. In addition, for about 6 months after fitting I found fine red particles in the float bowl. I assumed it was paint.

Stephen
Paint or rust Stephen? Would there be red paint on the inside of the tank?
I am not a fan of inline filters, and rely on the filter in the pump. I hope it does not have to cope with too much rust from the new tank.
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svenedin
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Re: welding petrol tank

Post by svenedin »

stuffedpike20 wrote: Wed Dec 31, 2025 3:09 pm
svenedin wrote: Wed Dec 31, 2025 2:33 pm
stuffedpike20 wrote: Wed Dec 31, 2025 1:35 pm Another update.
I bought a new tank for £276, which is a LOT of money to me, being unemployed.
The new tank has instructions to swill out with petrol before fitting, and there is a smell of waxoyl inside.
However, there are patches of rust to be seen inside the tank. I am going to inform the seller.

To sum up...I could only get a large capacity tank, which I did not need or want. The new tanks are not as good as originals. Mine already has rust.
£276 is a lot of money to some people.

Moderate your attitude brix.
I would add that my tank, new 3 years ago has rusted on the exterior where the very poor paint has literally fallen off. In addition, for about 6 months after fitting I found fine red particles in the float bowl. I assumed it was paint.

Stephen
Paint or rust Stephen? Would there be red paint on the inside of the tank?
I am not a fan of inline filters, and rely on the filter in the pump. I hope it does not have to cope with too much rust from the new tank.
Thank you for asking. I have found the photos I took at the time. It's rust. I used a magnet to determine whether it was rust or paint. Here are the photos I took when I cleaned out the pump filter after fitting the new tank. I was having some rough running issues which I think was caused by fine particles getting past the fuel pump filter into the float chamber and then the carb jet. It cannot be residue from the fuel pipe as I replaced the hard fuel line at the same time. Subsequently, I peered into the tank via the fuel sender hole and I could not see any rust......or paint.

So it is not such a simple decision to buy a new tank. I would rather have a good condition old tank with a repair or two than a new one. Of course a totally rusted old tank is no good at all.

Stephen

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IMG_9315.jpeg (1.11 MiB) Viewed 53163 times
IMG_9316.jpeg
IMG_9316.jpeg (1.53 MiB) Viewed 53163 times
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
stuffedpike20
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Re: welding petrol tank

Post by stuffedpike20 »

Maybe I WILL fit an inline filter! :o
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Bill_qaz
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Re: welding petrol tank

Post by Bill_qaz »

If you haven't already fitted your new tank, a good idea is to put some clean nuts, small bolts or ball bearing in the tank with a litre of diesel or paraffin (less flammable than petrol) tape up filler and sender unit openings. Give the tank a good shake in all directions then empty out into a bowl. Any contamination from assembly or flash rusting will be cleaned out. Repeat until no contaminants come out with the nuts or whatever used. Count them in and count them out :roll:
Well worth the effort before fitting :tu1:
Regards Bill
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Re: welding petrol tank

Post by stuffedpike20 »

Bill_qaz wrote: Wed Dec 31, 2025 7:15 pm If you haven't already fitted your new tank, a good idea is to put some clean nuts, small bolts or ball bearing in the tank with a litre of diesel or paraffin (less flammable than petrol) tape up filler and sender unit openings. Give the tank a good shake in all directions then empty out into a bowl. Any contamination from assembly or flash rusting will be cleaned out. Repeat until no contaminants come out with the nuts or whatever used. Count them in and count them out :roll:
Well worth the effort before fitting :tu1:
Thanks Bill.
The rust that I can see is in small patches, and not right at the bottom of the tank. The holes in the old tank were more or less in a line right at the bottom of the tank either side of the drain plug. It makes me wonder if ethanol, and lack of use of the car were factors in the tank rusting through.
I had to lengthen the arm to the sender unit float yesterdey. I worked out that if I had the float just off the bottom of the tank, it would foul on the side of the tank if I ever filled her up, (unlikely!). So I have had to compromise and make the arm too short. I will probably have to have about 4 gallons of petrol in before the guage moves now!
I have informed the seller of the rust, and sent a photo. I don't like the car sitting 'disabled' so I am going to fit the tank and try to use the car more in 2026.
Happy New Year Bill....and everyone on the forum. :tu1:
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Bill_qaz
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Re: welding petrol tank

Post by Bill_qaz »

At least you have a good reserve when on mt :D
Good luck hope you are sorted soon, happy new year :tu1:
Regards Bill
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svenedin
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Re: welding petrol tank

Post by svenedin »

brixtonmorris wrote: Wed Dec 31, 2025 2:35 am It's all just nonsense.

As much is I like originality, its a fuel tank.

If the tank has rust holes it means that the whole tank is rusty.
The metal thickness is reduced across the tank on the lower part.
I have also seen rust holes on the on the seam where the top half and lower meet.

A quote from stuffed pike. "Drilled some little holes in some thin steel....set the welder up...and filled them beautifully.
Moved over to the petrol tank. The result.....one of the little holes is now bigger!"

Why? because the metal is so thin due to rust.

Also this nonsense about new manufactured tanks are not as good as the original Stephen.
That may be the case. They don't make e type jags anymore.

Enjoy your rusty fuel tank.

The drain hole serves no purpose, you have an electric fuel pump to pump the fuel out.
No need to drain it out fully the drain hole as a new tank will not have any rust in it.
Unless you fill it with diesel
All the drain hole does is allow people to steal your fuel.

When you get a new hole in the skin of the tank you will lose your fuel again.
Hope it does not happen far from home.
I disagree that the drain "serves no purpose". It serves a very important purpose. Petrol is lighter than water so any water in the tank is at the bottom where it can corrode the tank. Emptying the tank via the fuel pump takes ages and will never completely drain the tank. As for allowing people to steal my petrol, they can steal it anytime with a syphon tube as I have an original fuel cap that does not lock.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
brixtonmorris
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Re: welding petrol tank

Post by brixtonmorris »

Ever heard of a locking petrol cap.

Love talking to you Steven.

You have a porcelain green morris like I do.
stuffedpike20
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Re: welding petrol tank

Post by stuffedpike20 »

I talked to the seller of the new tank yesterday.
They suggest emptying the tank completely if the car is to be laid up for the winter.
It would be hard to do that without a drain plug.

If you are using the car, the advice is to keep the tank as full as possible to avoid condensation... the original tank on the car formed holes on the top near the sender unit hole......but if you are not using it regularly, you will have a lot of stale petrol in the tank. You can't win. Modern petrol does not stay stable as long as the good old leaded stuff.
myoldjalopy
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Re: welding petrol tank

Post by myoldjalopy »

All in all, then, the best thing would be to use the car regularly throughout the year. Not infrequently, there are posts on here about cars that have not been used for several months and now won't start, run badly etc.
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svenedin
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Re: welding petrol tank

Post by svenedin »

brixtonmorris wrote: Sat Jan 03, 2026 2:58 am Ever heard of a locking petrol cap.

Love talking to you Steven.

You have a porcelain green morris like I do.
Yes I have heard of locking petrol caps but they are not original, look awful and I would not have one!

My Morris is Smoke Grey

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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svenedin
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Re: welding petrol tank

Post by svenedin »

myoldjalopy wrote: Sat Jan 03, 2026 9:49 am All in all, then, the best thing would be to use the car regularly throughout the year. Not infrequently, there are posts on here about cars that have not been used for several months and now won't start, run badly etc.
Absolutely agree. I do not think it is a good idea to "hibernate" a classic for months on end.

I do understand that others live in areas that have much more severe winters than relatively warm Southern England where I live. I think it just takes a bit of common sense. My advice would be, don't take the car out when there is salt all over the roads, don't take it out to get soaking wet and then sit wet for an eternity in a freezing cold garage. Take the car out on reasonable days according to the weather. Just a run around the local area is better than nothing but do go far enough to get the engine fully up to operating temperature. Giving the car regular runs avoids a myriad of problems e.g seized brake cylinders, sludged cooling system, stale fuel, general seizing of components etc.

As to stale fuel and water in the fuel consider using a fuel stabiliser such as STA-BIL (others available). I use this in the Morris during the winter when the car is used less frequently. I also use it in the fuel of garden equipment and have absolutely no trouble starting lawn mowers etc in spring. https://www.sta-bil.co.uk/shop/sta-2220 ... 73ml-21857

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
les
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Re: welding petrol tank

Post by les »

Can’t argue with that Stephen but my van is up on blocks now, and will stay that way until weather is warm. Even then it won’t be used much. I got my enjoyment from the restoration, so driving is secondary. Probably shouldn’t say this here but a couple of years back I bought my first new car, which has spoilt me, there’s no comparison !

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Re: welding petrol tank

Post by taupe »

Coming to this late but this stuff is good if it is really just a couple of small holes...

https://www.google.com/aclk?sa=L&ai=DCh ... &q=&adurl=

A welded repair is the best solution in my opinion but be sure to cut out ALL rusty and thinned steel areas first and ensure the tank has been thoroughly flushed and purged of all petrol residues and fumes before proceeding. You obviously need to be a competent welder capable of producing a weld free of defects blowholes etc

If the main horizontal seam is badly rusted and leaking then a welded repair is unlikely to be effective or worthwhile.

Taupe
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