We know there are many debates taking place right now about E10 petrol and how it will affect petrol tools. According to www.gov.uk, E10 petrol will become the standard grade in the UK from summer 2021.
E10 petrol will contain up to 10% renewable ethanol. This is intended to help reduce CO2 emissions, but we know that some of you may have concerns about how this will affect your petrol tools. We recommend in all of our owners’ manuals that you should only use high-quality brand-name petrol with a minimum octane rating of 90, but we can reassure you that petrol with an ethanol content of 10% or less, like the new E10 petrol will not cause a problem with your STIHL petrol tool.
In fact, our STIHL M-Tronic engines can still deliver full power when run using petrol with an ethanol content of up to 25% (E25).
However, petrol with an ethanol content of more than 10% can cause running problems in engines with a manually adjustable carburetor so should not be used in such engines.
As with any petrol, we would still recommend not storing your machine with E10 petrol in it, to avoid any blockages in the fuel delivery parts of the tool. We also recommend that you store E10 fuel for no longer than 30 days in order to minimize the degree of fuel segregation. This is where the moisture in the air binds with the ethanol and settles on the bottom of the canister. This can cause running problems and shaking the container does not completely resolve fuel segregation.
In some tools, it may also be necessary to readjust the carburetor to compensate for the changed composition of the fuel. We recommend that you visit a STIHL Approved Dealer for this.
Of course, if you are concerned about the use of ethanol in your machines, then you can always consider our premium, patented fuel formula, MotoMix. STIHL MotoMix is completely free from ethanol and has virtually no olefins or aromatic compounds. Emission-wise, this makes it a cleaner, more environmentally-friendly choice than regular fuels, plus it lasts longer so you can store it for up to 5 years, which is handy as MotoMix is available in 200 litre drums!
However, if you still want to use standard petrol, we are happy to reassure you that the new E10 petrol is fine to use in your STIHL petrol tools. You can search for the Instruction Manual for all current STIHL tools and some older versions here if you want to check any fuel recommendations. Let us know in the comments if you have any further questions.
Thanks for the advice.
You’re welcome! Let us know if you have any other questions.
Why don’t you make a product like Briggs and Stratton fuel fit, fuel fit works – fact.
Hi, thanks for your comment. We make our own stable fuels – MotoMix and Moto4Plus, which are a combination of premium fuel and premium oil, and are formulated to be the ideal fuel for STIHL machines. Thanks, STIHL GB
A list of stihl machines, past and present, that can and can’t take e10 fuel would be useful.
Thanks for your comment. All STIHL machines should be able to take E10 fuel, however, some may need an adjustment to the carburetor to compensate for the changed composition of the fuel. We recommend that you visit a STIHL Approved Dealer for this. Thanks, STIHL GB
Hi if I don’t use E10 fuel do I invalid my guarantee for stihl strimmer
Hi, thanks for your comment. You can use E10 fuel in your grass trimmer and it won’t invalidate the warranty. It must be mixed with a high quality 2-stroke engine oil at a fuel oil ratio of 50:1 – the required oil specification can be found in the user manual. Using your tool with stale fuel in it may also invalidate the warranty, so we recommend mixing in smaller quantities and not storing E10 fuel for longer than 30 days. Thanks, STIHL GB
Where can I order MotoMix
Hi, thanks for your comment. You can order MotoMix from any of our STIHL Approved Dealers. You can find your nearest one here: https://shop.stihl.co.uk/pages/dealer-locator
Thanks, STIHL GB
Hi there. Do you think my km94 rc kombi engines will be okay or would they need carb adjustment? I use the green hp ultra oil. Or would it be best going down the super unleaded route ?
Thanks
Hi, thanks for your comment. The new E10 fuel will be fine to use in your KM 94 RC. You may need to do a carb adjustment but only if it doesn’t run right after the switch. The KM 94 has been used globally for many years on E10 fuel so hopefully that will reassure you. Thanks, STIHL GB
Hi, The research that I have carried out suggests that bioethanol used in E10 fuel can cause degrading of rubber and plastic components such as fuel pipes, diaphragms etc. Would you please confirm if my brushcutter or chainsaw, both of which are over 5 years old, would be effected. Thanks
Hi, thanks for your comment. It is possible that in very old machines E10 may have adverse effects. But this was changed 18 years ago, so it is very old equipment where there could be some adverse effects. Either way, we always recommend that fuel is not stored in the machine for long periods. Thanks, STIHL GB
Hi, Do you think my old Stihl 051 & 044 chainsaws will be ok or need some adjustments.
We have all the latest stihl chainsaws at work. All of my Ms201 Tcm’s have had to have the spark plugs regularly cleaned after high carbon build up. This is unusual compared to their predecessors before E10 just wondered if there had been any other feedback like this after prolonged use since E10?
Hi, thank you for your comment. This isn’t an issue we’ve come across with links to the introduction of E10. Normally we’d associate carbon build-up with oil quality or an incorrect fuel mix ratio. Are you using genuine NGK CMR6H spark plugs provided by a STIHL Approved Dealer? Thanks, STIHL GB
Hello, I own and use a Contra Lighning, an 070 av, an 056av and an 045av!!! What fuel should I use to ensure no damage to piston/bores ? I have always run these on 20 to 1 mixture, perhaps that is why they are STIHL running well.
Hi, thanks for your comment. I’ve spoken to some of our technical experts here and they have said the following: For 045, 056 and 070 the recommended ratio in the owners’ manual is 1:40 for STIHL engine oil, or 1:25 for non STIHL-branded. The oil has a much bigger impact on piston damage than the choice of fuel – if you use HP Super or Ultra they will be the best thing for your machines and you won’t need to use as much. For the Contra Lightning, a 20:1 mix is absolutely fine, and we would recommend HP Super or HP Ultra for that too. I hope that helps, thanks, STIHL GB
I have a very nice BG 86C which all opf a sudden has stopped working, the primer bulb is not filling up when pushed. Ive called a service centre and they tell me this a regluar problem now with the advent of E10 fuels and could necesitate the carb having to be replaced, at quite a considerable cost. Is this correct? What is the company’s advice on such a situation?
Hi, thanks for getting in touch. If the machine has been left with E10 or even E5 fuel in for a while it can cause issues with carburettors. Our dealer network is skilled and proficient in the diagnostics of machines and fuel-related issues are common in their workshops. They can advise if a new carb or cleaning of the current carb would be most cost effective for you. If you would like further advice please contact enquiries@stihl.co.uk. Thanks, STIHL GB
Thanks foir the speedy reply. Can you tell me if Stihl are doing anything to aleviate this issue? The advent of E10 or E5 fuels is not going away, and emptying the fuel tank each time it is used, is less than convienent. Is there anything that you as manufacturers can do?
Is there not a fuel system additive that could be used that would stop that the E10/E5 fuels carb issues? Do Stihl recommend any products that are suitable?
Hi David,
STIHL changed gaskets and fuel lines more than 15 years ago to make them resistant to E10 fuels. We also recommend only filling up with as much as you need if you know the tool is not going to be used for some time.
Another solution is STIHL MotoMix (https://www.stihl.co.uk/STIHL-Products/Fuel-oils-and-canisters/MotoMix/21098-1633/MotoMix.aspx) which has a 5 year shelf life and is ethanol free and can be left in the tool. MotoMix is also cleaner burning, better for the tool and also the user and environment.
Here is a STIHL blog post to explain fully:
https://blog.stihl.co.uk/how-will-e10-petrol-affect-your-stihl-chainsaw/
Thanks
very informative and useful article. Thanks for sharing this
Hi seeing as there is no carburettor in a 5ooi would these saws be OK regarding the fuel going stale
Hi, thanks for your comment. It isn’t just the carburettor that can get blocked as a result of stale fuel. There are intricate parts on the injection system that could also be affected. Fuel segregation also occurs after approximately 30 days so we highly recommend fresh fuel is run in all our chainsaws. The MS 500i and professional M-Tronic chainsaws can use fuel with up to 25% ethanol but the important factor is that is it fresh. Thanks, STIHL GB
Good to know , but no one seems to be touching on the fact that any rubber parts on your machine will be attacked by E10 fuel .
Hi Steve, thank you for your comment. It is correct that in very old machines E10 can have adverse effects. However, changes were made to machine gaskets and fuel lines more than 18 years ago to make sure they are compatible for the future. 2-MIX machines are compatible with machines up to 10% ethanol content, whilst M-Tronic machines are compatible with up to 25% ethanol content and this is a situation we have been working with globally for many years now. Thanks, STIHL GB.