Weird Fuel Hose Leak
Discussion
Curious what you think…
Went into my garage and smelled fuel. The most recent bike I rode was an old 1996 GSXR 750… and I brimmed the tank before putting it away. Sure enough the sidestand was slightly wet with fuel.
I lifted the tank and found this interesting situation.
From the other side
So the fuel line from the petcock to the carbs is leaking,
But what’s with the ice? Is that what it even is? Ok, it’s cold outside, maybe -4C, but it still surprised me.
The hose is dripping too. 1 drop every 10 seconds or so. I cleaned off the “ice“ and then noticed that the hose is swollen and much softer than normal where the ice was.
Has anyone seen anything similar to this before. It looks like the hose has lost elasticity and is leaking from where it joins the petcock? The hose is supposed to be fuel line and is one year old. Ethanol related issue?
Went into my garage and smelled fuel. The most recent bike I rode was an old 1996 GSXR 750… and I brimmed the tank before putting it away. Sure enough the sidestand was slightly wet with fuel.
I lifted the tank and found this interesting situation.
From the other side
So the fuel line from the petcock to the carbs is leaking,
But what’s with the ice? Is that what it even is? Ok, it’s cold outside, maybe -4C, but it still surprised me.
The hose is dripping too. 1 drop every 10 seconds or so. I cleaned off the “ice“ and then noticed that the hose is swollen and much softer than normal where the ice was.
Has anyone seen anything similar to this before. It looks like the hose has lost elasticity and is leaking from where it joins the petcock? The hose is supposed to be fuel line and is one year old. Ethanol related issue?
ssray said:
E10 fuel at a guess, it absorbs water, it bugger's off and leaves ice
You need to replace any fuel hose with one that is E10 proof
That’s very possible, thanks. I’m amazed that there is that much water in the fuel. Or is the evaporation of the fuel causing local cooling which is freezing water in the air around the hose? In other words it’s not water in the fuel, but in the air around the hose?You need to replace any fuel hose with one that is E10 proof
Kawasicki said:
That’s very possible, thanks. I’m amazed that there is that much water in the fuel. Or is the evaporation of the fuel causing local cooling which is freezing water in the air around the hose? In other words it’s not water in the fuel, but in the air around the hose?
Ethanol is hygroscopic and it looks like it has absorbed as much water as it could.trickywoo said:
Kawasicki said:
That’s very possible, thanks. I’m amazed that there is that much water in the fuel. Or is the evaporation of the fuel causing local cooling which is freezing water in the air around the hose? In other words it’s not water in the fuel, but in the air around the hose?
Ethanol is hygroscopic and it looks like it has absorbed as much water as it could.Ice forming due to the fuel evaporating.
Latent heat of vaporisation is lost, so the hose cools, frost forms due to moisture in the air on the now-cold surface.
If the water was originally dissolved in the petrol/ethanol, its freezing point would be well below zero.
I once had an old car which suffered from carburettor ice formation on cold damp Autumn mornings.
You could drive for a about 5 minutes, stop and see ice all over the outside of the carb. Wait a few minutes for the heat to rise from the engine, all would be OK from then on.
That fuel hose is long past its chuck-by date, as well as any ethanol compatibility issues.
On my bike, the short little hose from the brake reservoir to the master cylinder went porous after 18 years, little tiny droplets of brake fluid all over it!
Latent heat of vaporisation is lost, so the hose cools, frost forms due to moisture in the air on the now-cold surface.
If the water was originally dissolved in the petrol/ethanol, its freezing point would be well below zero.
I once had an old car which suffered from carburettor ice formation on cold damp Autumn mornings.
You could drive for a about 5 minutes, stop and see ice all over the outside of the carb. Wait a few minutes for the heat to rise from the engine, all would be OK from then on.
That fuel hose is long past its chuck-by date, as well as any ethanol compatibility issues.
On my bike, the short little hose from the brake reservoir to the master cylinder went porous after 18 years, little tiny droplets of brake fluid all over it!
OutInTheShed said:
Ice forming due to the fuel evaporating.
Latent heat of vaporisation is lost, so the hose cools, frost forms due to moisture in the air on the now-cold surface.
If the water was originally dissolved in the petrol/ethanol, its freezing point would be well below zero.
I once had an old car which suffered from carburettor ice formation on cold damp Autumn mornings.
You could drive for a about 5 minutes, stop and see ice all over the outside of the carb. Wait a few minutes for the heat to rise from the engine, all would be OK from then on.
That fuel hose is long past its chuck-by date, as well as any ethanol compatibility issues.
On my bike, the short little hose from the brake reservoir to the master cylinder went porous after 18 years, little tiny droplets of brake fluid all over it!
Cheers, I agree completely.Latent heat of vaporisation is lost, so the hose cools, frost forms due to moisture in the air on the now-cold surface.
If the water was originally dissolved in the petrol/ethanol, its freezing point would be well below zero.
I once had an old car which suffered from carburettor ice formation on cold damp Autumn mornings.
You could drive for a about 5 minutes, stop and see ice all over the outside of the carb. Wait a few minutes for the heat to rise from the engine, all would be OK from then on.
That fuel hose is long past its chuck-by date, as well as any ethanol compatibility issues.
On my bike, the short little hose from the brake reservoir to the master cylinder went porous after 18 years, little tiny droplets of brake fluid all over it!
I bought a new fuel hose, well two actually. The first one was a standard car (reinforced) fuel line. It was actually too stiff to seal/conform to the petcock fitting and leaked even harder! The second hose was purchased from a motorcycle workshop, it is the same dimensions - but with a woven overlay. Weirdly it’s not sealing either, even with the help of a little jubilee hose clamp. Sometimes the simplest issues aren’t easy to fix!
Kawasicki said:
OutInTheShed said:
Ice forming due to the fuel evaporating.
Latent heat of vaporisation is lost, so the hose cools, frost forms due to moisture in the air on the now-cold surface.
If the water was originally dissolved in the petrol/ethanol, its freezing point would be well below zero.
I once had an old car which suffered from carburettor ice formation on cold damp Autumn mornings.
You could drive for a about 5 minutes, stop and see ice all over the outside of the carb. Wait a few minutes for the heat to rise from the engine, all would be OK from then on.
That fuel hose is long past its chuck-by date, as well as any ethanol compatibility issues.
On my bike, the short little hose from the brake reservoir to the master cylinder went porous after 18 years, little tiny droplets of brake fluid all over it!
Cheers, I agree completely.Latent heat of vaporisation is lost, so the hose cools, frost forms due to moisture in the air on the now-cold surface.
If the water was originally dissolved in the petrol/ethanol, its freezing point would be well below zero.
I once had an old car which suffered from carburettor ice formation on cold damp Autumn mornings.
You could drive for a about 5 minutes, stop and see ice all over the outside of the carb. Wait a few minutes for the heat to rise from the engine, all would be OK from then on.
That fuel hose is long past its chuck-by date, as well as any ethanol compatibility issues.
On my bike, the short little hose from the brake reservoir to the master cylinder went porous after 18 years, little tiny droplets of brake fluid all over it!
You need fuel hose that is Ethanol-proof (at least 30% is ideal IMHO) I bought some for my kit cars from Car Builder Solutions in Kent - very helpful and they know their stuff. before buying it I tried getting some locally (a total joke) one 'motorsport specialist' just offered me 8mm hose saying 'it's good for petrol - we've used it for years with no issue" When I asked about E10 fuel he didn't even seem to know what it was! No marking on hose, so I didn't buy it. I wanted some small-bore hose for my vacuum advance recently and I noticed the local independent car spares and cycle shop has E10 proof of same, and know about the marking etc - the one outfit in town that appear to have knowledge!
Google what standards it needs marked on hose (buying from internet auction site probably best avoided!)
I bought a new fuel hose, well two actually. The first one was a standard car (reinforced) fuel line. It was actually too stiff to seal/conform to the petcock fitting and leaked even harder! The second hose was purchased from a motorcycle workshop, it is the same dimensions - but with a woven overlay. Weirdly it’s not sealing either, even with the help of a little jubilee hose clamp. Sometimes the simplest issues aren’t easy to fix!
I don't know what happened, as my note got mixed into previous posts....... anyway, here's what I had to say. Hope it helps
You need fuel hose that is Ethanol-proof (at least 30% is ideal IMHO) I bought some for my kit cars from Car Builder Solutions in Kent - very helpful and they know their stuff. before buying it I tried getting some locally (a total joke) one 'motorsport specialist' just offered me 8mm hose saying 'it's good for petrol - we've used it for years with no issue" When I asked about E10 fuel he didn't even seem to know what it was! No marking on hose, so I didn't buy it. I wanted some small-bore hose for my vacuum advance recently and I noticed the local independent car spares and cycle shop has E10 proof of same, and know about the marking etc - the one outfit in town that appear to have knowledge! biggrin
Google what standards it needs marked on hose (buying from internet auction site probably best avoided!)
You need fuel hose that is Ethanol-proof (at least 30% is ideal IMHO) I bought some for my kit cars from Car Builder Solutions in Kent - very helpful and they know their stuff. before buying it I tried getting some locally (a total joke) one 'motorsport specialist' just offered me 8mm hose saying 'it's good for petrol - we've used it for years with no issue" When I asked about E10 fuel he didn't even seem to know what it was! No marking on hose, so I didn't buy it. I wanted some small-bore hose for my vacuum advance recently and I noticed the local independent car spares and cycle shop has E10 proof of same, and know about the marking etc - the one outfit in town that appear to have knowledge! biggrin
Google what standards it needs marked on hose (buying from internet auction site probably best avoided!)
Don't forget if you're measuring the ID of your old pipe it will have stretched while being fitted.
I'd be using this...
https://www.ebay.co.uk/itm/123897137866?_trkparms=...
I'd be using this...
https://www.ebay.co.uk/itm/123897137866?_trkparms=...
A few years since I had to replace some hoses, but I went for the SAE J-rated stuff correct for E-10 and above fuel.
This isn't an EFI bike I guess, but anyone looking for hoses to go 'in the tank' needs different hose, the outer cover is ethanol resistant too.
The wrong hose will often go stiff, which stresses the joins and causes leaks. A few quid extra is better in the long run.
But none of it lasts forever, there are a lot of vehicles on the road with 'time served' fuel hoses.
This isn't an EFI bike I guess, but anyone looking for hoses to go 'in the tank' needs different hose, the outer cover is ethanol resistant too.
The wrong hose will often go stiff, which stresses the joins and causes leaks. A few quid extra is better in the long run.
But none of it lasts forever, there are a lot of vehicles on the road with 'time served' fuel hoses.
Decky_Q said:
I've been replacing alot of fuel hoses lately, bikes and off road equipment seem to be most common. Dont buy the replacemnt on ebay as I did that once and the hose was destroyed again in no time. Local motor factors have any size you need and it will be e10 compliant.
My local motor factors are ignorant of E10 
But this is Norfolk, so in 10 years maybe......
I am alright Jack said:
Don't forget if you're measuring the ID of your old pipe it will have stretched while being fitted.
I'd be using this...
https://www.ebay.co.uk/itm/123897137866?_trkparms=...
Don't mess around trying to save money (which could cost more in long run with bike on fire!) Hose should have spec on it. Suitable specs are listed online.I'd be using this...
https://www.ebay.co.uk/itm/123897137866?_trkparms=...
Maybe buy this
https://www.carbuilder.com/uk/ethanol-proof-fuel-h...
Which is notably intentionally smaller to achieve a good fit.
I have no connection to CBS, being just a very satisfied customer of many years.
Some of the reinforced hose is very stiff, it's made to cope with high pressures from EFI.
If you can't get it to seal on the fittings, then either try a smaller size, or maybe an unreinforced hose if it's not a pressure situation.
The proper fuel hose clips or the 'ear clips' you tighten with pincers are more effective than joobly clips in small sizes, so I get a proper hose clip first.
When you do up a small joobly clip, it ceases to be round. Sometimes the sping clips are better.
If you can't get it to seal on the fittings, then either try a smaller size, or maybe an unreinforced hose if it's not a pressure situation.
The proper fuel hose clips or the 'ear clips' you tighten with pincers are more effective than joobly clips in small sizes, so I get a proper hose clip first.
When you do up a small joobly clip, it ceases to be round. Sometimes the sping clips are better.
OutInTheShed said:
Some of the reinforced hose is very stiff, it's made to cope with high pressures from EFI.
If you can't get it to seal on the fittings, then either try a smaller size, or maybe an unreinforced hose if it's not a pressure situation.
The proper fuel hose clips or the 'ear clips' you tighten with pincers are more effective than joobly clips in small sizes, so I get a proper hose clip first.
When you do up a small joobly clip, it ceases to be round. Sometimes the sping clips are better.
Spring clips are better (that's why OEM use them), but ensure you use the correct size clip for the hose!If you can't get it to seal on the fittings, then either try a smaller size, or maybe an unreinforced hose if it's not a pressure situation.
The proper fuel hose clips or the 'ear clips' you tighten with pincers are more effective than joobly clips in small sizes, so I get a proper hose clip first.
When you do up a small joobly clip, it ceases to be round. Sometimes the sping clips are better.
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