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Soldered copper fittings on a fuel line
bumpy - 16/4/19 at 05:43 PM

I am a bit stuck trying to route my copper fuel line and a compression fitting wont fit the space.

My question: Is it acceptable for the IVA and indeed my safety to insert a soldered (Yorkshire) fitting at this difficult position?

Thanks Chris

bonzoronnie - 16/4/19 at 06:29 PM

My gut feeling says no.

I know the use of soldered joints are not permitted on the fuel feed lines on domestic oil fired boilers.

[Edited on 16/4/19 by bonzoronnie]

MikeR - 16/4/19 at 07:25 PM

I hope soldering is allowed as its what i've done (but not been via iva) to add olives something to pipes for the rubber hose to grip.

Not sure about bends etc.

bozla - 16/4/19 at 07:45 PM

I wouldn't use plumbing solder - do a braze using map gas and refrigeration rod.

tegwin - 16/4/19 at 07:57 PM

My worry would be embrittlement of the heat effected area causing a potential fracture.

Probably ok if you use a silver solder and then heat treat the part to soften it again.

bozla - 16/4/19 at 08:05 PM

I don't think that would be an issue. The heat would anneal the copper (soften) if anything. This joint is used in refrigeration systems over 40 bar the world over.

mark chandler - 16/4/19 at 08:06 PM

Petrol attacks soft solder, you need to braze really.

bumpy - 16/4/19 at 08:18 PM

quote:
Originally posted by mark chandler
Petrol attacks soft solder, you need to braze really.


Is this hearsay or can you show technical proof?

avagolen - 16/4/19 at 08:24 PM

From what I understand the question, the fuel seal will be a jubilee clip. The soldered olive will only be to prevent it sliding off. I have done this, but I have only 2 psi for carbs.

loggyboy - 16/4/19 at 10:00 PM

Why would you need to do this? Fuel lines can be bent to almost any angle and come in huge lengths.

bumpy - 17/4/19 at 07:13 AM

quote:
Originally posted by loggyboy
Why would you need to do this? Fuel lines can be bent to almost any angle and come in huge lengths.


The complete length of pipe is already fitted but in hindsight I am concerned it is running a little too close to the chassis at one point, hence the wish to carry out a local 'repair'. There is insufficient room to use a spanner on compression fittings.

Mr Whippy - 17/4/19 at 08:45 AM

quote:
Originally posted by mark chandler
Petrol attacks soft solder, you need to braze really.


is this the case? I mind the old metal floats looked very much like they were soldered together? and I'm sure that's how you fixed any leaks too.

[Edited on 17/4/19 by Mr Whippy]

Mr Whippy - 17/4/19 at 08:49 AM

quote:
Originally posted by bumpy
quote:
Originally posted by loggyboy
Why would you need to do this? Fuel lines can be bent to almost any angle and come in huge lengths.


The complete length of pipe is already fitted but in hindsight I am concerned it is running a little too close to the chassis at one point, hence the wish to carry out a local 'repair'. There is insufficient room to use a spanner on compression fittings.


not sure how you could be too close to the chassis since most pipe clips are mounted to the chassis or bodywork and so the pipes are usually a few mm away from the surface... I think a photo would help here if only to get other suggestions for a solution. With pipes such as fuel & brake pipes it is fine to sleeve them in a section of rubber hose where they are to be clamped to the surface, I used this on the Landy brake lines and fuel lines that are clamped to the engine and it's how the factory did it too.

40inches - 17/4/19 at 08:54 AM

quote:
Originally posted by bumpy
quote:
Originally posted by loggyboy
Why would you need to do this? Fuel lines can be bent to almost any angle and come in huge lengths.


The complete length of pipe is already fitted but in hindsight I am concerned it is running a little too close to the chassis at one point, hence the wish to carry out a local 'repair'. There is insufficient room to use a spanner on compression fittings.


Move the pipe away from the chassis or slide a length of larger diameter fuel hose over the pipe to the point of contact or cut the pipe and fit a piece of R9 hose into the pipe?
I can't visualise the need for a fitting in the length of piping.

40inches - 17/4/19 at 09:08 AM

quote:
Originally posted by Mr Whippy
quote:
Originally posted by mark chandler
Petrol attacks soft solder, you need to braze really.


is this the case? I mind the old metal floats looked very much like they were soldered together? and I'm sure that's how you fixed any leaks too.

[Edited on 17/4/19 by Mr Whippy]


That was pre Ethonal Mr Whippy, from a paper on Ethanol in fuel:

"Certain materials commonly used with gasoline may be incompatible with high-level ethanol blends, causing them to degrade and contaminate the fuel. Metals that have been shown to degrade over time in the presence of high-level alcohol blends include brass,(floats & jets) lead, zinc(carb bodies) and lead-based solder.

Nonmetallic materials that degrade when in contact with ethanol include natural rubber, polyurethane, cork gasket material, leather, polyvinyl chloride (PVC) polyamides, and certain thermoplastic or thermoset polymers."

Although I don't know what constitutes a "high level" most fuels in the UK seem to be around 10%.

bumpy - 17/4/19 at 09:30 AM

quote:
Originally posted by 40inches
quote:
Originally posted by Mr Whippy
quote:
Originally posted by mark chandler
Petrol attacks soft solder, you need to braze really.


is this the case? I mind the old metal floats looked very much like they were soldered together? and I'm sure that's how you fixed any leaks too.

[Edited on 17/4/19 by Mr Whippy]


That was pre Ethonal Mr Whippy, from a paper on Ethanol in fuel:

"Certain materials commonly used with gasoline may be incompatible with high-level ethanol blends, causing them to degrade and contaminate the fuel. Metals that have been shown to degrade over time in the presence of high-level alcohol blends include brass,(floats & jets) lead, zinc(carb bodies) and lead-based solder.

Nonmetallic materials that degrade when in contact with ethanol include natural rubber, polyurethane, cork gasket material, leather, polyvinyl chloride (PVC) polyamides, and certain thermoplastic or thermoset polymers."

Although I don't know what constitutes a "high level" most fuels in the UK seem to be around 10%.


I agree, petrol and or ethanol degrade plastics and rubbers by leaching out the oils and lubricants from which they are formed. This makes the materials brittle or porous.

Here we have metal fused to metal, which unless someone can provide proof of the chemistry is completely different.

gremlin1234 - 17/4/19 at 10:51 AM

quote:
Originally posted by 40inches
Although I don't know what constitutes a "high level" most fuels in the UK seem to be around 10%.

standard unleaded is at least 5%ethanol
you can get ethanol free petrol ie:
quote:
Esso super unleaded petrol (Synergy Supreme+ Unleaded 97) is ethanol free (except in Devon, Cornwall, the Teesside area and Scotland). We would therefore advise anyone who has concerns about the presence of ethanol in petrol to use Synergy Supreme+ – providing they do not fill up in Devon or Cornwall, the Teesside area or Scotland.

https://www.esso.co.uk/fuels-faqs

ALLAN 14 - 17/4/19 at 11:27 AM

If you are in a tight spot because the pipe is pointing directly at the chassis would not a Banjo fitting be a better way to go,
All types are available they have been used to join Weber Carburetors together for donkey's years great for use in a tight spot.
Just a thought.
Allan

MikeR - 17/4/19 at 12:14 PM

NB soldered joints are an instant fail on boats from what I've read this morning.

bumpy - 17/4/19 at 12:27 PM

quote:
Originally posted by MikeR
NB soldered joints are an instant fail on boats from what I've read this morning.


Yes that's the message I picked up. I think its less to do with vibration failure, or fuel erosion of the solder, and more to do with the joint melting apart in a fire and broadcasting more fuel into the conflagration.

[Edited on 17/4/19 by bumpy]