Leaking SU carb (float bowl lid - inlet pipe)

[Doublerat]

The leak is really a slight weeping at the joint of the brass inlet pipe and the float bowl lid. I can't see any way to repair it. I have seen soldering / brazing kits that claim to be able to join aluminium and brass but I am a bit reluctant to try this in case I do more harm than good!

It's a single 1-3/4" su on the marina 1800 engine

I have tried http://sucarb.co.uk a bit pricey but the lid assemblies are out of stock anyway, and the usual ebay search hasn't come trumps yet

Does anyone have any suggestions or a spare lid that that I can buy?

Any help will be much appreciated

Thanks

Phil

[djj_engineer]

Re: Leaking SU carb (float bowl lid - inlet pipe)

What fuel pump does the car have?

[Cameron F]

Re: Leaking SU carb (float bowl lid - inlet pipe)

It sounds quite unusual for the brass inlet to leak. First check the flexible hose, it may not be sealing because its old - chop an inch off and retry the join. It could be the hose clip isn't sealing the rubber flexible hose properly so you get a fine mist of fuel which gathers around the inlet pipe. My money would be on the flexi pipe, esp if its old and has been used with modern fuels.
Second thing to check is the float valve and needle - if it sticks then the fuel can build up to such a level it leaks (though normally through the overflow or top gasket). A bit of crud from the rubber pipe or out of the tank can be all it takes - whilst you are at it examine the needle for ridges or wear.

If on the other hand you can physically move the inlet then the lid is scrap. You could try bodging it with something like plastic padding metal but it will be a bodge. Good luck - let us know what you find.

[Doublerat]

Re: Leaking SU carb (float bowl lid - inlet pipe)

What fuel pump does the car have?

It is the standard Marina mechanical pump

[Doublerat]

Re: Leaking SU carb (float bowl lid - inlet pipe)

It sounds quite unusual for the brass inlet to leak. First check the flexible hose, it may not be sealing because its old - chop an inch off and retry the join. It could be the hose clip isn't sealing the rubber flexible hose properly so you get a fine mist of fuel which gathers around the inlet pipe. My money would be on the flexi pipe, esp if its old and has been used with modern fuels.
Second thing to check is the float valve and needle - if it sticks then the fuel can build up to such a level it leaks (though normally through the overflow or top gasket). A bit of crud from the rubber pipe or out of the tank can be all it takes - whilst you are at it examine the needle for ridges or wear.

If on the other hand you can physically move the inlet then the lid is scrap. You could try bodging it with something like plastic padding metal but it will be a bodge. Good luck - let us know what you find.

It's certainly unusual and has been driving me scatty!

I have tried replacing the hose, hose clip and the float valve and needle

Pulling the hose back from the face of the lid, re-sealing it and with the engine running a very slight weeping of fuel can be seen from around the inlet pipe and running down above the overflow/vent

The inlet pipe itself as a dent in it so it must have taken a knock at some time in it's life and maybe that is the cause of the leak

P1100620.JPG

The pipe isn't loose and there must just be the smallest capillary leak in the join to the lid

Epoxy gave a temporary fix but as you say it's a bodge, not satisfactory and only temporary anyway, but the fact that it did stop the flow confirmed the source. I guess that this is all I can do until I find a replacement

Thanks for the suggestions and I will let you know how I get on

[b_caswell]

Re: Leaking SU carb (float bowl lid - inlet pipe)

http://www.ebay.co.uk/itm/1-3-4-SU-Carburettor-Spares-Repair-/263056605722?hash=item3d3f65421a:g:-1QAAOSwZ4dZLZIM

A bit scruffy but the right price

[HairyDave]

Re: Leaking SU carb (float bowl lid - inlet pipe)

Try a local breakers yard, not many about now or Stuart Miles he breaks Marinas. 07517 62640. I have had gear from him, but not recently. At a push what diameter is it, I may have one in my box of useful bits.

[h_m_cumming]

Re: Leaking SU carb (float bowl lid - inlet pipe)

If you're still stuck contact me and I'll machine it out and fit a new spigot.
Hugh.

[Doublerat]

Re: Leaking SU carb (float bowl lid - inlet pipe)

Hi Hugh

I think I am sorted now with a replacement but thanks for the offer. If the replacement doesn't work out I will take you up on it

[h_m_cumming]

Re: Leaking SU carb (float bowl lid - inlet pipe)

You're welcome.

[Doublerat]

Re: Leaking SU carb (float bowl lid - inlet pipe)

Replacement lid fitted and the problem is now cured

Thanks for all the help / advice

Phil

[b_caswell]

Re: Leaking SU carb (float bowl lid - inlet pipe)

Well done now that your fixed you could have a go at sweating in with solder the old one, if it works you have a spare if it don't nothing lost really.