Ethanol in Fuel

Panky

admin 2.0
Staff member
A member of our local car club wrote this article and published it in the club website. Scary and could explain a number of problems we see including 'snakeskin'

Ethanol in fuel
I have ben asked several times about the amount of ethanol being added to petrol to satisfy the 'green lobby' and EU regulations. As with all these things the answer is it's not straightforward. Petrol companies are permitted to add up to 5% ethanol without declaring it. I believe most major suppliers are currently pretty close to this figure. It is worth noting that there is some pressure for the EU (and that would include us) to go up to 10% without companies having to declare it.

It is claimed that even at 10% the amount is unlikely to cause damage to a 'standard car'. From reading articles I would suggest that classics are not 'standard cars' in this respect - more later.

It is possible for far larger amounts of ethanol to be added provided this is declared by the retailer at the point of sale. Some garages are currently selling E85 petrol and as the name suggests this has 85% ethanol and this should only be used in cars where the manufacturer states in can be used.

Several overseas markets have sales of 100% ethanol but their cars are specifically modified and adapted for this use. Such countries include Brazil and South Africa.

So what can happen if fuel containing ethanol is used in older classic cars? There are many reports of different problems but the most likely ones fall into three groups:

Loosening of pre existing contaminants in petrol tanks and fuel systems. Here the ethanol almost acts as a stripper loosening deposits including rust from any surface it comes into prolonged contact with. This material can then block filters and carburetor jets.

Chemical reactions with existing rubbers, resins, plastics and sealants etc. The effects on resins glass fibre fuel tanks can be of great concern but 'O' rings can turn to a sort of mush and plastic fuel lines can either leak or turn brittle depending on chemical composition. Fuel tanks with rubber liners are at risk and this is one for the racing fraternity to be concerned about. Having said that there are some classics with tank liners which may also be at risk.

The final issue is, I believe, of importance not only to classic car owners but to all users of this stuff. Ethanol is hydroscopic (like some brake fluids). That means it attracts and retains water. This can come from any source including water vapour in the air. The greater the moisture content in the ethanol the less likely it is to burn. If saturated it simply will not burn. That means if a car is not used for long periods the amount of moisture in the fuel may increase to a point where the engine simple will not start. In this case the fuel system will need draining and fresh fuel added to rectify the problem. Not an issue if the vehicle is used regularly but may become one where a car is laid up for several months over winter say.

Short answer to the original question is that it is highly likely that fuel purchased currently contains some ethanol probably less than 5% but still enough to potentially cause issues.




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Two's company
 
ethanol in the fuels already a big enough pain even at 5%. ive had to have the webers off my comps van and had to replace the 2 main securing washers on the fuel intake lines with copper washers as the fibre gaskets were just useless resulting in fuel leaks over the exhaust from the nuts coming undone. These werent old gaskets either as the carbs were professionally overhauled when the van was rebuilt. Its also happening on sunbeam ti's and avenger tigers running twin 40 webers as i know of at least 3 that have gone up in flames and a couple of others that faired slightly better because the owners carried a fire extingusher.
also with rootes painting the inside of their tanks from new snakeskin is now a massive problem across the entire rootes range ive had to put inline filters in every fuel line in all my cars/commercials.
 
It used to be that BP Ultimate and Shell Optimax(now known as V-Power)were the only fuels not to contain methanol - now it's only the BP option, for now[V]

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Two's company
 
And another little thought - methanol disolves fibre glass. So any such repair on a petrol tank will fail and if you have a coach-built with a fibre glass body be careful when you fill up[xx(]

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Two's company
 
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