E10 what to make a fuel tank and rigid pipes out of?

[milliemarlin]

In another thread an owner is showing off his brand new Aluminium tank. A work of beauty it is too.

Both my current Cabrio and my under construction Sportster have Aluminium tanks.

For the rebuild above and my Sportster the pre-2011 engines will probably always be run on E5 petrol. My Cabrio has a Zetec engine manufactured in Brazil where E25 (25% Ethanol) fuel is standard. So if I had the right fuel tank, rigid and flexible pipes she could run on E10.

I am also a bit worried that IVA inspectors will start to require E10 compatible components regardless of the engine. New owners may not realise the need for E5 and use E10. Ruining the engine is a problem but leaking fuel could be a disaster.

Flexible pipes purchased from a reputable source marked “SAE J30 R9” are easy enough.

But what is the best material for a new tank?

What is the best material for rigid fuel lines?
Paul

[ggrum]

I plan to put an article in the next Pitstop magazine which may answer some questions. The problem with Ethanol is that it is hygroscopic which means it absorbs moisture which can cause corrosion of copper, lead/tin alloys (i.e. solder) and zinc. It is also a solvent which attacks some rubbers, plastics and even fibre glass. I believe aluminium alloy is not affected. The main problem will be with cars that spend most of their time stored with fuel in the system. It is easy enough to replace all the flexible fuel hose with good quality stuff to the standard mentioned by Paul above but the problem will be with seals and diaphragms etc on old fuel systems. Also, if the float in the carb float chamber is the soldered brass type it may eventually leak as the solder is dissolved. The same is true of the fuel gauge sender float.
Most rigid fuel lines in our cars are probably copper but I believe the rate of corrosion from the Ethanol is very low with this metal. I suppose if you wanted to be really sure then replace them with stainless steel but not so easy to fit.

There are additives on the market that neutralise the effect of Ethanol but, in my opinion, the best solution is to use the E5 high octane fuel or 'super unleaded'. It may be a few pence per litre more expensive than the E10 stuff but with the sort of mileages most of us do in our cars it won't make much difference and its better for performance anyway, even if the engine is in standard tune.

Geoff

[milliemarlin]

Thanks Geoff, I had not even considered the fuel gauge sender or pump. I look forward to reading the article. Looks like I will be using E5 for quite some time.
Paul

[kahawi]

Blagged a shopping trip to Sainsbury’s in the Marlin, I discover the tank is pretty empty. Ever since I’ve owned the car I’ve gone for a local garage’s BP* ‘Ultimate’ (as already said here at 1,000miles per year it’s not going to break the bank) Unfortunately Sainsbury’s was sold out of everything except E10.

According to Ford, my PI 2.3ltr DOHC is good for E10, (OK, the Marlin pipes, filters, fuel sensor etc. may not be, but one tank full isn’t going to do any immediate damage), so I topped up.

To my surprise the car is running like a dream, it positively purrs along and seems to have a bit more oomph than normal. A bit of a dilemma now:-

I too have an alloy tank, with a plastic float and the odd (possibly paper) filter lurking along the return line. I intend to replace all the rubber pipes this winter, they’re showing signs of cracking at the joins from old age and probably the wrong ‘jubilee clips’ etc. The inline pump will need to be looked at, but given the cost of pipes it’s probably worth replacing the pump at the same time.

Gut feel says to me that my incredibly clean ally tank is going to take a good while to corrode through and I understand we can get an additive in the last tankful, ready for the winter layup (?) which should alleviate even that problem.

I’m less inclined to panic, about E10, but maybe I’m missing something?

* Other petrol brands are available

[ggrum]

As far as I'm aware the impact of ethanol on aluminium alloy is negligible so alloy tanks should be ok.

[milliemarlin]

I found this which looks to be well informed from High Powered Media (HPM) written in 2014. HPM is an American website that purports; “Fact not fiction. Science not speculation. Engineering publications written by engineers, for engineers.”
https://www.highpowermedia.com/Archi...nk-and-ethanol

Although light, aluminium is a highly reactive metal that relies on an oxide layer for protection against its corrosion. This oxide layer occurs naturally, and the low levels of ethanol such as E10 (10% ethanol, 90% gasoline) or the 5% ethanol blend often found in Europe are usually not a problem. The problem occurs principally when the ethanol content in the fuel is increased beyond these levels. The issue, although complex, generally centres on the presence of water in the fuel.

Corrosion behaviour of aluminium alloys in ethanol fuels
http://www.process-design-center.com...ol%20Fuels.pdf

This 9 page report looks like a very comprehensive analysis (I didn't read it all). It is full of pictures of surface structures and graphs. I’ve copied an excerpt from the last paragraph of a lengthy conclusion (I'm not sure about the nickel coating):

The chemically deposited nickel layer exhibits a very good resistance to alcohol fuels, independent of temperature and water or ethanol content. The mass loss was only a few hundredths of a percent. Macroscopic and microscopic observations of the surface of the coated specimens revealed an undamaged material free of corrosion products.

So I guess the aluminium should be alright but any sealants, rubbers, etc will be suspect.
Paul

[kahawi]

fbhvc-logo.png

Quite a good E5-E10 article by the Federation of British Historic Vehicle Clubs

https://www.fbhvc.co.uk/fuels

[paulbeebee]

Hi folks - Paul here in Cirencester with a Marlin Cabrio bought last year (July 2021) I’m going to replace the fuel tank so does anyone know where I can obtain a replacement alloy tank which will fit? Many thanks

[scott h]

I had an alloy tank made by OBP. They have a section on their website for bespoke items such as fuel tanks. I emailed a drawing and they gave me a price within a day or two. After I paid for it the tank arrived in ten days.

[jon_cox]

You can try Forge Motorsport. They are just south of Gloucester so not far from you. They do customer alloy work. I sold them a 3D CAD system many years ago for this very purpose.
They have a division called Forge Engineering for this custom work.
https://www.forgemotorsport.co.uk/
https://www.forgeengineering.co.uk/