Thread: Chainsaw fuel warning

all my fuel containers are clearly marked pulp, ulp and 2 stroke, I run my old 7-10 A Mcculloch on pulp 95, it's been hard to get places to fix it but its a ripper of a saw!

Did your fuel contain ethanol ie E10?

I don't let E10 fuels anywhere near my mower, whipper snipper, blower vac, chainsaw, generator or boat as it can cause a terminal illness.

Regards
Twosheds

Hi all,
there was a heap of good info on this subject on the Treeworld forum but sadly it has been closed down. The key points were,
Only run pure ULP no Ethanol,
Use fuel stabiliser,
Use Stihl or Husqvarna synthetic oil at the correct ratio.
Run it a bit fat if you can.
I make up 20 litres at a time, and run my 034, my 3120, my Eager Beaver and my husky brush cutter on the same mix with no problems. According to one of the forums, the yanks get different model Stihls to us and they are all complaining about them. There is heaps of info to read on Arborist.com, if you have the time.
Rgds,
Crocy.

I generally agree wih everything that has been said, with one exception. My
guy (40+ years in the business)says dont use E10 in any of your equipment - blowers, mowers, whipper snipper or chainsaws.
Hesays that they are not designed for unleaded as per cars. Hope that helps. Drillit.

Originally Posted by BobL

....The average two stroke user thinks that if some oil is good then adding a little (or a lot more) should be better.....

Yup, I have struck this too.

BIL is a yard maintenance man & he runs all his 2 stroke stuff so oily that it smokes.
He did this to my Mum's whipper snipper & it blocked the muffler mesh with greasy black soot.

I use the synthetic oil at slightly lower ratio (more oil) but never to the point that it smokes.

If you can see & smell blue smoke, you are blocking up you motor exhaust & your lungs.

Originally Posted by Drillit

I generally agree wih everything that has been said, with one exception. My
guy (40+ years in the business)says dont use E10 in any of your equipment - blowers, mowers, whipper snipper or chainsaws.
Hesays that they are not designed for unleaded as per cars. Hope that helps. Drillit.

This hoary chestnut has been discussed ad nauseum on the Chainsaw forum on the Arboristsite. The response by Stihl engineers is that their saws (even their older ones) are designed to cope with high alcohol content gasoline. Don't forget that some countries have been using fuel containing alcohol for decades, many use only petrol containing some alcohol, and some with a much higher content of alcohol than E10. In these countries there has not been the complete death of two stroke motors because they ono about the following.

The problem with petrol that contains alcohol is that it can absorb more water than no-alcohol fuels. The worst case scenarios are when small amounts of petrol sit around in non-air tight metal cans for many months especially in cold weather. Some photo's posted on the Arboristsite show fuel stored under these conditions transferred to a clear container with a cm+ layer of water at the bottom of the fuel. The same applies to the fuel tanks on small motors.. If the fuel is stored in plastic with a good seal and the container is a full as possible the problem goes away.

So another reason to use fresh petrol and store it properly.

Stihl recommend a maximum of 10% ethanol in the fuel, or E10.

Gasoline Guidelines for STIHL Outdoor Power Equipment | STIHL USA Mobile

Originally Posted by Big Shed

Stihl recommend a maximum of 10% ethanol in the fuel, or E10.

Gasoline Guidelines for STIHL Outdoor Power Equipment | STIHL USA Mobile

Thats most likely a general coverage for outdoor power gear for North American conditions i.e. it gets much colder there than it does here.

As far as chainsaws go, countries like Brazil have a mandated E20 - E25. Big forest industries there too. They even have their own Stihl factory producing some older model Stihls no longer available in the US or Europe or here. Maybe they modify the saws to cope with the higher ethanol contents but somehow I doubt it.

I only buy my chainsaw fuel from petrol stations with high volume sales; to avoid getting old fuel to start with.

And, as recommended by Bob, I always buy the next octane level up.

And, always use Husky or Stihl 2-s oil.

Disposal of old fuel is a prob.

Anyone putting it in their 'older model' car? As in 20 yrs old ... and adding just a few litres to a nearly full tank.

Originally Posted by NeilS

.
.
Disposal of old fuel is a prob.
Anyone putting it in their 'older model' car? As in 20 yrs old ... and adding just a few litres to a nearly full tank.

I used to do that in our old Mitsubishi 1986 van but now we have two diesels it's not so easy.
I even used to do it to a late model Subaru but one time I there was not much in the tank and it made bit of a mess of the injectors.

If it's not too old it goes in the mover/whippersnipper otherwise I evporate what I can and add the residue to the waste oil container.

Thanks, Bob.

I bought my first chainsaw from a Husky Dealer, not the big box store. The guys there said to run only high octane fuel in it. If you run it all day, every day, regular octane will be okay, but still, not the best. Only problem I had was when I didn't use it for a few months in the summer. The fuel can, a plastic one was on a bench that got an hour or so of sun every day. Well, it 'distilled' the mix down, and I ran one tank full through. Ate lunch, and tried to start it up again. I couldn't even turn it over. The cylinder and piston were coated in a reddish heavy film. Won't make that mistake ever again.

robo hippy

And another thing robo hippys post just reminded me of, in one of the posts in Treeworld, someone said that the newer enviro friendly synthetic 2 stroke oils have a habit of settling out of the fuel mix. So now I try and leave only enough fuel in my machines to keep the diaphragms wet, and shake the hell out of the containers before refueling. Also from one of the previous posts, some one mentioned that all the european saws are made to run on ethanol blended fuel. That maybe OK for newer machines designed for it, but all our older gear does not have ethanol resistant piping or diaphragms in them.
rgds,
Crocy.

Originally Posted by Old Croc

According to one of the forums, the yanks get different model Stihls to us and they are all complaining about them. There is heaps of info to read on Arborist.com, if you have the time.

As far as major brands go we we have been getting the same basic model as US and Canada for some time - if you check the specifications on the US and AU Stihls you will see they are the same models. There are some small differences like a slightly bigger B&C oil pump on saws like the Stihls 660 for the Aussie model, but to meet similar EPA requirements we get the same fuel delivery systems and strangled mufflers etc. The countries that get the different models are places like Mexico and South America which have factories that still make some non-OHS saws that for example may not have a chain brake. or non-EPA compliancy on Mufflers etc.

Originally Posted by Old Croc

And another thing robo hippys post just reminded me of, in one of the posts in Treeworld, someone said that the newer enviro friendly synthetic 2 stroke oils have a habit of settling out of the fuel mix.

I've not heard of this but I have heard of old school lubes doing this. The first thing I do when I pick up any saw is shake it, a habit I picked up from my old many who used chainsaws in the 50's and 60's.

So now I try and leave only enough fuel in my machines to keep the diaphragms wet, and shake the hell out of the containers before refueling. Also from one of the previous posts, some one mentioned that all the european saws are made to run on ethanol blended fuel. That maybe OK for newer machines designed for it, but all our older gear does not have ethanol resistant piping or diaphragms in them.

This may be relevant to 30+ year old saws. In Brazil where they have used 20 to 25% ethanol fuel blends for many years, Stihl still make some older models saws (some models that go as far back as 40 years) and they have to survive with these high concentrations of ethanol.