Ethanol & rubber

[anonymous-user]

Fuel return to tank. Fitted May 2019. Rubber completely disintegrated.

[GAjon]

This is a big worry. It’s not only the fuel lines, gaskets and seal’s throughout are being affected.
We’re just servicing the fuel injectors on a 2010 Mazda MPS with direct injection and the injector internal seals have been eaten by ethanol fuel.

[TwinKam]

It's only the beginning...
I have recommended Esso Supreme+ to all my customers, family and friends.

[alabbasi]

That's just a crappy rubber hose. 10% ethanol has been around in the US since the 70's and the US is the biggest car market. It won't hurt anything unless fuel sits for extended periods.

[anonymous-user]

alabbasi said:

That's just a crappy rubber hose. 10% ethanol has been around in the US since the 70's and the US is the biggest car market. It won't hurt anything unless fuel sits for extended periods.

It’s not the fuel sitting, that doesn’t seem to cause the problem - it’s the vapour. This was a fuel return pipe and sections where the fuel sits are fine but those above fuel ‘level’ have gone to crumb. Yes it’s crap pipe too, but that’s happened in just 3 years.

So it’s ultra-crap. But looked perfect when it was fitted.

[Moto]

If using E5 fuel is hose erosion not a problem or does the 3 years just become 6 years? Curious to know how often the hoses need replacing to avoid a potential nasty incident.

[alabbasi]

V6 Pushfit said:

So it’s ultra-crap. But looked perfect when it was fitted.

Yes but not likely due to ethanol given that it's been used for yonks, every car manufacturer will source fuel hose that's ethanol resistant. This hose was likely sourced from a factory in Asia where it was made to the lowest $. Factories in Asia will make you anything you like to the lowest $.

[TwinKam]

But with the knowledge that ethanol is such a potent solvent, it makes sense to fit ethanol-resistant hoses AND choose a fuel with the minimum ethanol content (besides which it has a poor calorific value).

[anonymous-user]

I’ve already replumbed everything on everything with Gates Barricade apart from the Tuscan between the.tank and electric pump and the return which I was planning for in a couple of weekends. I wasn’t going to bother with the fuel return as it’s just a zilch pressure feed back to the tank….
Went for a first 2022 short run yesterday (12 miles) and got back to see a pool of petrol on the driveway where it had been standing for 5 mins before leaving and a text from a neighbour i passed as I left ‘you are leaking fuel’.
Bullet dodged.
I disconnected the return, lowered the carb pressure on the regulator to compensate and we did a 50 mile trip last night.
Pipe now ordered - 27313 for 1/4” return and 27314 for 5/16” supply.

I would recommend anyone with the shiny stainless steel armoured pipe of dubious source to replace it as soon as they can with ethanol proof stuff.

Most of yesterday was spent grappling with an 82 year old handbrake setup and finding I need some unobtanium parts, so all in all a typical day!

[markymarkthree]

V6 Pushfit said:

I’ve already replumbed everything on everything with Gates Barricade apart from the Tuscan between the.tank and electric pump and the return which I was planning for in a couple of weekends. I wasn’t going to bother with the fuel return as it’s just a zilch pressure feed back to the tank….
Went for a first 2022 short run yesterday (12 miles) and got back to see a pool of petrol on the driveway where it had been standing for 5 mins before leaving and a text from a neighbour i passed as I left ‘you are leaking fuel’.
Bullet dodged.
I disconnected the return, lowered the carb pressure on the regulator to compensate and we did a 50 mile trip last night.
Pipe now ordered - 27313 for 1/4” return and 27314 for 5/16” supply.

I would recommend anyone with the shiny stainless steel armoured pipe of dubious source to replace it as soon as they can with ethanol proof stuff.

Most of yesterday was spent grappling with an 82 year old handbrake setup and finding I need some unobtanium parts, so all in all a typical day!

I would also recommend anyone with the black cotton braided fuel pipe that looks the part in classic cars to replace it.
I purchased some at the NEC 4 years ago and it went rotten within 2 years

[steveo3002]

braided is a mugs game ...looks all race car but you cant inspect it and spot minor cracks

[anonymous-user]

steveo3002 said:

braided is a mugs game ...looks all race car but you cant inspect it and spot minor cracks

Very true. I couldn’t see. Where the leak was from so cut out a section, blocked one end and put an air line on it to reveal a good 2 foot of crumbed pipe.

It says ‘nitrile’ on the pipe, well if it is then nitrile rubber is not ethanol resistant!

[Moto]

I'm inclined to agree with Neil in that new rubber products are of inferior quality to old rubber products. The scientific reasons for this are beyond my knowledge but I do wonder whether it has something to do with the shift away from natural rubbers to synthetic rubbers. I also question the cause being ethanol as it seems to me that modern rubbers fatigue quickly across multiple applications - brake / clutch cylinders, oil hoses and even suspension bushes.

Moto

[OldGermanHeaps]

Is there a test I can do to some components to check they will be good with e10 before i fit them?
I am about to do a both engines out rebuild on my 1997 jet boat and the only petrol available on the water at loch lomond is e10 i think. I bought rebuild kits for all 4 carbs and all 4 fuel pumps but its quite a time consuming job I dont want to have to do it twice if it reacts badly so I would like to test the parts beforehand. The boat is low single digits mpg so dragging enough jerrycans of premium from shore petrol stations will be both a ballache and expensive.

[Blib]

I bumped into the boss of our local Porsche independent this afternnon and asked him about E10 fuel and my 964.

He told me that in emergencies you can use an additive. Is this correct?

[alabbasi]

Blib said:

I bumped into the boss of our local Porsche independent this afternnon and asked him about E10 fuel and my 964.

He told me that in emergencies you can use an additive. Is this correct?

No, this has been talked to death in the US 30 years ago. E10 is fine provided that it does not sit too long. If it does, then the ethanol will break down resulting in water in the tank causing rust and gumming up the fuel system. The only motor that I would avoid using ethanol gas in is lawn equipment. If you drive your car on a regular bases, there will be no problems.

[Blib]

Ah. So, I could run E10 in my 964 throughout the summer so long as I run it almost dry then fill up with E5 for the winter months?

[anonymous-user]

OldGermanHeaps said:

Is there a test I can do to some components to check they will be good with e10 before i fit them?
I am about to do a both engines out rebuild on my 1997 jet boat and the only petrol available on the water at loch lomond is e10 i think. I bought rebuild kits for all 4 carbs and all 4 fuel pumps but its quite a time consuming job I dont want to have to do it twice if it reacts badly so I would like to test the parts beforehand. The boat is low single digits mpg so dragging enough jerrycans of premium from shore petrol stations will be both a ballache and expensive.

I think all you can do is find out from the parts suppliers I’m afraid.

[OldGermanHeaps]

Wa chung ho off aliexpress i'm afraid. Genuine ones are very hard to source in the uk, usa only and ridiculously priced, all the uk dealers just seem to sell the chinese ones with a markup so I just went straight to source.
I thought maybe measure them, leave them in a jug of e10 for a week then measure them again?

Edited by OldGermanHeaps on Sunday 3rd July 18:59

[alabbasi]

Blib said:

Ah. So, I could run E10 in my 964 throughout the summer so long as I run it almost dry then fill up with E5 for the winter months?

If you mean that you lay the car up during the winter, you could just use a product called Stabil. I would suggest running the car monthly for at least 30 minutes keep the fuel moving.