Sending unit leaking gas

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nickacb
998 Cooper
Posts: 281
Joined: Tue Nov 01, 2011 4:31 am
Location: Mexico City

Sending unit leaking gas

Post by nickacb »

So my petrol tank is a constant source of trouble my mini is a mk1 with the sending unit with six screws

The problem is that the gas is leaking thru the screws of the sending unit, the bottom one being the more problematic. In a couple of minutes it forms a puddle on the floor of the boot. The other screws also leak but only a little

I put the cork gasket but still leakead then i put the cork gasket and a DIY rubber together and still leaked. No leaks thru the edges thou

Hope someone could suggest a solution please
Old English White
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Re: Sending unit leaking gas

Post by Old English White »

Personally I have always used a little blue hylomar on the screw threads on assembly. Never had a problem with leaks. No doubt other owners will have a different solution.
woodypup no 2
Basic 850
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Re: Sending unit leaking gas

Post by woodypup no 2 »

Have you got the copper washers under the screws ?
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Dr.Mabo
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Re: Sending unit leaking gas

Post by Dr.Mabo »

With regard to the seal, it is worth thinking outside the box. The cork seal is not exactly the best solution. Other English and Italian vehicles use the same diameter and screw arrangement for their tank units. There are thicker rubber gaskets available that seal much better. There are numerous offers for small money on ebay.

I once accidentally restored and coated a tank with a screwed tank sender for a newer MK1 Mini. In order for the fuel gauge to work, however, I needed a sensor with a clamping ring. With the help of a self-made adapter ring, the better rubber seal and 6 screws with standard washers, it is still leak free.

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My previous project:
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Peter Laidler
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Re: Sending unit leaking gas

Post by Peter Laidler »

'leaking through the screw' can only mean that the petrol is seeping along the threads of the bottom screw and no gaskets are going to cure that. I'd suggest that you need new screws with perfect threads. I'd suggest that the petrol is leaking past all(?) of the threads but leaching towards the bottom - where it's running out!

New full-thread bolts, washers, gasket and petrol resistant sealant as OEWhite suggests
nickacb
998 Cooper
Posts: 281
Joined: Tue Nov 01, 2011 4:31 am
Location: Mexico City

Re: Sending unit leaking gas

Post by nickacb »

Thanx everyone for your suggestions, for those interested I solved the problem with a set of new screws and a set of o-rings
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