E10 fuel

[lesxk8]

I have a  year 2000 XK8 4.0 litre V8. Is it Ok to use the E10 fuel or should i upgrade to the super unleaded 97 octane?

[Wrinkly]

32 minutes ago, lesxk8 said:

I have a  year 2000 XK8 4.0 litre V8. Is it Ok to use the E10 fuel or should i upgrade to the super unleaded 97 octane?

Les, Hope this helps you.    https://www.gov.uk/check-vehicle-e10-petrol

Best Wishes and Regards, John

[John Duff]

I know that my 2000 X100 will run ok on E10 fuel but are the rubber up to it? 
I just had a failure of the rubber pipe leading to the fuel filter. Job done now but how about the rest of the pipes in the system?

Thanks

[N6 JMX]

Hi John, this is a bit of a debate about the length of string! Modern cars such as your X-100 will run perfectly fine on E10 fuel as the ECU (brain) will assess and compensate for the higher quantity of ethanol (the E) and the subsequent lower energy density. Logically, the car's perform marginally better on E5, because of the higher energy density, which may also give rise to a marginal increase in the MPG, but lots of different parameters play out on that issue so it would be a pure side benefit.

As to the rubber hoses, yes, ethanol will degrade the rubber hoses in fuel systems, but the reality is that the fuel system has already been exposed to ethanol during its life span on standard unleaded before the introduction of E5 and E10. Would you need to replace the hoses in a 24 year old fuel system, yes. Would you need to do it sooner when using E10, not necessarily, but it is a wise precaution but on an age related basis as opposed to a pure E10 related basis.

Hope this helps.

N6 JMX

[PDS]

Some forecourts are now restricting the use E5 so E10 is only available when filling up. I have had a number of Classic cars over the years and whenever I put E10 in I always dossed the tank with REDEX Petrol System Cleaner which protects against corrosion from E10 fuel and never had a problem. Not used E10 in the XKR yet but if I do I will put in some REDEX.

[JOC Admin]

I run my BMW Z3 on Super-Unleaded only, but as you are saying PDS it's becoming more difficult nowadays to find stations with an E5 pump.
I recently spoke to a forecourt attendant and he said they were not stocking it until the new pumps are installed - quite why it needs new pumps to dispense it, or whether it is accelerated decay of the rubber, etc in the current E5 pumps?

Either way, the benefits far outweight the extra cost of the E5 in my opinion.
Between 1500 and 2500 rpm the engine was always flat on acceleration....switched to E5 and its where it should be now - smooth as silk all through the rev ranges.

Not only the driveability of the car has transformed but the economy is much better too. I don't see going back to E10 has any benefit for older cars.
However, running E5 in my motorbikes seems to have very little noticable benefit that I can determine (as yet).