Rubber fuel hose query.

[Mad4slalom]

Hi all , someone I was talking to today mentioned that the biggest cause of fires in classic cars was the old rubber fuel pipes degrading from the ethanol in fuel and causing leaks onto hot engines. Any one here replaced their old rubber lines and know where on the car to look for said lines. I think mine are mainly metal fuel pipes but guess there are some rubber sections to allow for movement and vibration. Recommendations for correct spec rubber pipes welcome , mine was restored over 12 years ago now so thought worth renewing again for peace of mind. TiA.

 

[johng]

On mine there are short rubber hoses between the steel lines and fuel tank and at the front between the steel lines and the fuel pump. I replaced all of mine but that was easy as I had the body off at the time. None of my hoses are in positions where they could actually leak onto a hot engine, but then who wants to empty their fuel tank onto the floor anyway. The line from my fuel pump to the carb is all steel, rubber in this line would be more of a concern.

 

[Mad4slalom]

Hi all , someone I was talking to today mentioned that the biggest cause of fires in classic cars was the old rubber fuel pipes degrading from the ethanol in fuel and causing leaks onto hot engines. Any one here replaced their old rubber lines and know where on the car to look for said lines. I think mine are mainly metal fuel pipes but guess there are some rubber sections to allow for movement and vibration. Recommendations for correct spec rubber pipes welcome , mine was restored over 12 years ago now so thought worth renewing again for peace of mind. TiA.

On mine there are short rubber hoses between the steel lines and fuel tank and at the front between the steel lines and the fuel pump. I replaced all of mine but that was easy as I had the body off at the time. None of my hoses are in positions where they could actually leak onto a hot engine, but then who wants to empty their fuel tank onto the floor anyway. The line from my fuel pump to the carb is all steel, rubber in this line would be more of a concern.

Thanks, I will inspect mine to see what is rubber and get some new hose just due to the age I think.

 

[teamzr1]

Also check if the fuel filter if now has rubber couplers to connect fuel lines
and as Ethanol crap has degraded EVAP hoses if car has it as that vents fuel vapor and PCV hoses

Now get to it

 

[Mad4slalom]

Also check if the fuel filter if now has rubber couplers to connect fuel lines
and as Ethanol crap has degraded EVAP hoses if car has it as that vents fuel vapor and PCV hoses

Now get to it

Off to vette room to check right now !

 

[antijam]

Hi all , someone I was talking to today mentioned that the biggest cause of fires in classic cars was the old rubber fuel pipes degrading from the ethanol in fuel and causing leaks onto hot engines. Any one here replaced their old rubber lines and know where on the car to look for said lines. I think mine are mainly metal fuel pipes but guess there are some rubber sections to allow for movement and vibration. Recommendations for correct spec rubber pipes welcome , mine was restored over 12 years ago now so thought worth renewing again for peace of mind. TiA.

Make sure the hose you use to replace meets SAEJ30R9. This is resistant to modern E5 and E10 fuels. There are short lengths of straight hose connecting the metal fuel lines to the tank and a formed hose connecting the metal line to the fuel pump.
Even if your current hoses have not suffered significant ethanol degradation, unless they've been replaced at some time they could well be dry rotted by now.
Replacement is on my own 'jobs to do' list. Dropping the tank is not particularly difficult but I'm having trouble working up the energy to do it. Although I can find no visual leaks on my car there is a persistent smell of petrol while driving ( and a fuel consumption of 14 mpg ) so rotted hoses is one possibility to eliminate.

 

[mickn]

The 'S' shaped rubber hose at the front of the fuel lines before the fuel pump perished on my '73 a couple of years ago and caused no end of issues with the tiny rubber particles blocking the carb. It took at least a couple of carb rebuilds to sort it out so be warned.

 

[Mad4slalom]

Make sure the hose you use to replace meets SAEJ30R9. This is resistant to modern E5 and E10 fuels. There are short lengths of straight hose connecting the metal fuel lines to the tank and a formed hose connecting the metal line to the fuel pump.
Even if your current hoses have not suffered significant ethanol degradation, unless they've been replaced at some time they could well be dry rotted by now.
Replacement is on my own 'jobs to do' list. Dropping the tank is not particularly difficult but I'm having trouble working up the energy to do it. Although I can find no visual leaks on my car there is a persistent smell of petrol while driving ( and a fuel consumption of 14 mpg ) so rotted hoses is one possibility to eliminate.

 

[Mad4slalom]

Here are the rubber bits I can see, can I buy these in a kit or just off the roll? Were all renewed when restored in 2011/12. They all look good but its a time thing too

 

[antijam]

Your water and front end fuel hoses look fine. If they were replaced around 2012 I wouldn't have thought they'd need replacing yet although no markings on the fuel lines indicating that they're ethanol resistant are visible.
If the fuel tank was refitted as part as part of the restoration then I'd assume the short rubbers would have been replaced at the same time. Trouble is you can't easily tell without dropping the tank.

 

[teamzr1]

It is the inside of the hoses that are affected by Ethanol, so cannot tell if degraded

Is this fuel hose collapsed in the inner side of the bend and reducing fuel flow ?
Or is it the fuel return line ?

I rather use AN fittings than those hose clamps

 

[Mad4slalom]

Your water and front end fuel hoses look fine. If they were replaced around 2012 I wouldn't have thought they'd need replacing yet although no markings on the fuel lines indicating that they're ethanol resistant are visible.
If the fuel tank was refitted as part as part of the restoration then I'd assume the short rubbers would have been replaced at the same time. Trouble is you can't easily tell without dropping the tank.

I have messaged peter in buffalo and hope he can confirm all querys . Really handy to be in touch with the person who stripped and re built the car

 

[Roscobbc]

Mad4 - I notice the smaller diameter fuel return line clipped next to 'feed' line - where does that connect to?

 

[teamzr1]

It looks like hose with the SAE standard, rating label 30R9 works for Ethanol blend
R6 or R7 is not rated for Ethanol, so check the print on hoses that comply to SAE

 

[Mad4slalom]

Mad4 - I notice the smaller diameter fuel return line clipped next to 'feed' line - where does that connect to?

I will have a look after breakfast , when you say hose is ok for ethanol blend fuel , is our fuel only e5 or 10 so that is a blend or is that different in the usa?

 

[CaptainK]

I've been thinking of replacing my fuel hoses too for a similar reason. They all look ok, but its the inside that would be rotting from fuel etc. Wondered if it might help with the petrolly smell I sometimes get in the garage after driving the car. Probably just the fuel evaporating from the carb as I don't use the Vette that often.

 

[Mad4slalom]

I've been thinking of replacing my fuel hoses too for a similar reason. They all look ok, but its the inside that would be rotting from fuel etc. Wondered if it might help with the petrolly smell I sometimes get in the garage after driving the car. Probably just the fuel evaporating from the carb as I don't use the Vette that often.

I get that fuel smell a bit after I put her away hot , I think its more evap than leak tho, i have had a more neat petrol smell if I completely brim the tank so I leave an inch at the top now, besides, it never stays full for long !!🫣

 

[Mad4slalom]

I will have a look after breakfast , when you say hose is ok for ethanol blend fuel , is our fuel only e5 or 10 so that is a blend or is that different in the usa?

Hi ross, just checked and it connects to the bottom of the fuel pump ,

 

[Mad4slalom]

It is the inside of the hoses that are affected by Ethanol, so cannot tell if degraded

Is this fuel hose collapsed in the inner side of the bend and reducing fuel flow ?
Or is it the fuel return line ?

I rather use AN fittings than those hose clamps

View attachment 27577

Ok , any pics of the an fittings. Do they need a crimp tool?

 

[Roscobbc]

A couple of observations. A few years back (10/15 years of more) and before all this ethanol crap became legislated there was some 'pretty' looking stainless steel braided hosing on the market. I bought some (along with quite of few others who would experience later the same issues as I did).......it was poor quality far eastern manufactured garbage. No one though to check it out for SAE no's. It was sold at car shows etc. I used it for fuel feed from hard line at top of engine to the carb and to connect the two Holley floats. Roll-on a year or so and the rubber inner hose simply disintegrated, but being encased with the stainless braiding was invisible. Fortunately the smell and leak we quickly spotted - others were not so lucky.
On my C3 even though the fuel lines are metal at the fuel pump they may be hosing connecting metal pipe. Certainly at the rear of the car there is flexible hosing connectly the hard line to the fuel tank......and that one ethanol was in common use caused a leak on mine......again fortunately quickly smelt. spotted and identified.

And Mad - I was curious about the 'return' line - I know its to circulate fuel in the 'line' from front of car back to the tank and helps prevent percolation - on mine it connects to a three way metal canister fuel filter just in front of the passenger side cylinder head.