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Collection, Preservation and Display of Old Lawn Mowers

E10 fuel - Ransomes 14


E10 fuel.  I can find only a couple of passing references to this on the forum but nothing definitive.

I have been running my 1964 Ransomes 14 mk2 with the 65cc BSA engine quite happily on 95 ron E5 unleaded fuel since I inherited it from my father in the Spring and I think that's what he ran it on since buying it in 2016. 

However since 1 Sept as we know this is no longer available. I have a bit of E5 left but will have to fill up the jerrycan soon.

So the choice going forward is 95 ron E10, or the E5 super unleaded which is usually 97 or 98 ron depending where you get it from.

Any advice welcome on which of those two options would be best - and also whether I should now start using an addative.



wristpin Tue, 21/09/2021

Since the introduction of E5 the rule of thumb has been to only buy fuel in a quantity that you will use in a month - unlike my old Dad who , in the 50s and 60s would fill two or three Jerrycans at a time to keep the old Dennis running in a large garden.   This still applies ,  but in addition, the advice is that we should buy “ super” such as Shell V Power or BP Supreme as  for now it’s still only E5. I believe some Tesco stations still do an E5 98/99 octane brew.

There is some suggestion to stay with E10 but to use one of several available ethanol beating additives.

wristpin Tue, 21/09/2021…

Couldn't make much sense of this link - jumping all over the place, but would rather stick with the one month recommendation . Bear in mind that mower tanks have a large surface area to volume and a lot of aeration from vibration. Having spent over 30 years in the mower trade and can safe fully say that your average mower users, domestic or commercial  are not known for fuel hygiene .

Adrian Sun, 10/10/2021

My guess would be pre-ignition ("pinking"), which can damage the valves.

I suspect that the older the mower, the less there is in the fuel system that might be damaged by the alcohol content of E10 - it certainly shouldn't touch anything metal - but the fuel will absorb more water over time than E-free would have, which isn't going to do its burning ability much good.

Anyone know anyone in Brazil with a lawn? They've been running stuff on bioethanol for donkey's years.

Floydism Thu, 21/10/2021

High octane fuel would lessen the danger of knock/pinking, so I'd be quite confident to use it in an old engine without the fear of damaging it, it won't make bigger bangs than regular old 95. I'd suggest a switch to 'super' as the government have promised to leave it alone!

I recommend to my customers to use a fuel stabiliser too, as their machines are often layed-up for 4-5 months at a time (much like most mowers) and dropping the contents of the bowl before leaving them alone for the season. the stabilisers don't help if there's a puddle of water at the bottom of the tank but they'll help the fuel stay healthy enough to at least fire-up the next time it's run.

I've also started to fit little sediment bowls to my own machines, they do a great job of catching any water before it reaches the carb, as long as you keep an eye on it!

wristpin Fri, 22/10/2021

I've also started to fit little sediment bowls to my own machines, they do a great job of catching any water before it reaches the carb, as long as you keep an eye on it!

Been doing that for years by just using an length of translucent fuel pipe brought down in a loop between tank and carb.  - held with a cable tie if necessary. Easy to spot anything accumulating in the bottom of the loop.

When I had the business all workshop fuel was treated with stabiliser on the day it was bought throughout the year . Saved a lot of potential problems, not just on mowers after winter lay up but also on other infrequently used kit   such as cultivators, chainsaws and generators . We even used to sell a couple of bottles a year to a customer who dosed his Lotus Elan for its winter lay up.

Adrian Fri, 22/10/2021

Funnily enough about a week after after my post I thought "Water!", but I've not actually got round to mentioning it before anyone else did.

Given that round here the first sign of spring is a middle-aged man cursing a recalcitrant Mountfield, I should probably heed my own advice...