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MG MGA - Good advice re Carb fuel hoses

There was good advice in the MGA Register newsletter this month about regular replacement of the steel braided carb fuel hoses. I checked mine today and you can see from the attached photo that the carb to carb rubber hose had seen better days. From looking at the receipts that came when I bought the car a few years ago I think it will be at least 23 years old! Interestingly the other braided fuel hose to the rear carb wasn't rubber but some kind of plastic. All now replaced with new hoses and a potential disaster averted.



Tim Prime

Hi Tim,
a few years ago, I began to notice a series of fuel leaks from the main fuel pipe under the car.
I found out that the original steel fuel line had been replaced with a "rubber" pipe covered in a woven fabric reinforcing layer.

Obviously, the pipe had been affected by the ethanol in modern fuel and after fixing a few leaks, I decided to replace the whole pipe with an 8mm cupro-nickel metal pipe.

I could have fitted a replacement steel fuel pipe from Moss which has screw connections to the pump, but I run a non standard high performance Facet fuel pump which has push-fit connections and so it was easier to decide on the cupro-nickel pipe in the end.

The new pipe has solved all the leaks and should be good for very many years.

I have fitted an ethanol-proof braided fuel pipe at the carb end it seems to be holding up well too.

Cheers
Colyn
Colyn Firth

A lot of people don't realize that a steel braided hose is not just made of steel. It's only a rubber hose covered in steel. They go bad just like any other rubber hose. There are some hoses made, like the ones sold by Moss Motors, that have a teflon liner inside the rubber. These should last a very long time compared to traditional rubber. Hoses made today SHOULD all be ethanol-resistant, but any older hoses may not be and I consider them dangerous. I make it a point to change the hoses in my cars no less than once every ten years if not sooner. It's a very small expense compared to an engine fire.
Steve Simmons

I wondered if the plastic rear hose Tim mentioned was some sort of PTFE type.

Steve and others,
I also wondered if the carb hoses were steel braided not just for bling but also to allow the tight bends they have as rubber fuel hose bend spec is quite shallow?

I think ethanol is often given the full blame on rubber fuel hoses when it has highlighted the age of the rubber. In more recent decades some rubber has been so piss-poor than it can't last weeks let alone years or decades and nothing to do with ethanol (which wasn't being used when my three different lots of 1/4" fuel hoses, from three different motor factors in three different counties, failed about 16 years ago.

Steve,
I don't know the Moss Motors Teflon lined rubber hose, is the rubber just to keep the traditional look or is it required to protect and aid the bends? Is the rubber outer still required if there is a steel braided top coat?

https://www.speedflowshop.co.uk/teflon-hose-stainless-steel-braided-2459-p.asp

https://www.goodridge.co.uk/pages/hose-range-and-benefits-quick-guide
Nigel Atkins

My guess is that the teflon inner would not hold up very well without the rubber outer protection, and would be easy to kink. It would also require some sort of compression fitting to seal the ends.
Steve Simmons

I too need to replace the braided hoses linking the carbs on my Twin Cam. They are many years old and this thread has prompted me to take action. Advice welcomed - would it be best to buy the necessary fully made up Teflon lined braided setup complete with banjo ends, from the usual suspects (Burlen, Moss, Brown & Gammons, etc), no doubt at high price, or use one of the specialist hydraulic pipe firms like Nigel mentioned (Speedflow, Goodridge) and get them to make up the Teflon lined braided pipes using my old banjo ends. That’s assuming the banjos are re-useable?
Which way to go?
Bruce.
Bruce Mayo

Steve,
thanks that's what I thought, I couldn't see the PTFE being thick enough or ridged enough if smooth outer and inner walled. The Goodridge link shows all the (bling) fittings.
Nigel Atkins

Bruce,
my opinion for the little it's worth and I don't know what you have available on the Isle of Wight. Having dealt with, bought from and had work done by, on many occasions, I don't have a particularly high regard for those three and would avoid them where possible and sooner give my custom to more local concerns, where possibly. Braided and PTFE hoses can be made up by other places, as you can see by the links the materials are available and not just from those manufacturers(?) or suppliers, they can be custom made. But as I have done, too many times in the past, it is often easier to by from the usual suspects and I recognise that not all their products are low quality and they don't always give poor service.
Nigel Atkins

The hoses on my MGA are from Moss (USA) and they are of high quality. They've been on for many years without issue. A local hose shop should be able to do a good job also. Just take your old hoses with you and they can re-use the fittings.
Steve Simmons

This is exactly why I have never been a fan of braided hoses on general, and replaced the fuel lines at about five year intervals. Why anyone fits braided brake hoses is beyond me......
Dominic Clancy

This thread was discussed between 04/11/2022 and 14/11/2022

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