Multiple Fuel Mix Ratios

ky8t · May 22, 2010

I have several two cycle power tools, some of which recommend a 40:1 fuel/oil mix while others specify 50:1. I believe I have seen 32:1 also. Do I need to make two different cans of fuel, or can I just use one mix for all? If so, what mix is best for all?

oliver28472 · May 24, 2010

My shindawa weed eater is 40:1. The dealer doesn't sell the 40:1 mix any more. They said 50:1 was OK so that's what I use in it now. Makes it easier because my chainsaws are 50:1.

westbrooklawn · May 24, 2010

Buy Amsoil Saber 100/1 synthetic and mix it at 80/1 with 93 octane fuel and use it in everything... problems solved.

om21braz · May 24, 2010

Used Opti-2 at their specified ratio in all types equipment since 1999. No problems or issues to report related to fuel mix. Not cheap, but it's worked well IMHO.

s78wingrider · May 24, 2010

If you want to use 50-1 mix and get it right, mix with 8 tenths of a gallon. I used 50-1 in my back pack leaf blower when it was new and ruined the motor. lucky for me, they fixed it under warranty. Aaron

WH401 · May 26, 2010

I second using Amsoil Saber at 80:1. I have a Stihl BR600 back pack blower that requires 50:1, a Stihl FS90R trimmer that requires 50:1, a Stihl MS390 chainsaw that requires 50:1 and a cheap Weed Eater hand held blower that requires 40:1. I use Amsoil Saber at 80:1 mix w/ 89 gas in all of them and they run great. They actually run and perform a lot better on that mix then they did on their recommended mix. I've ran that mix for the last few years and haven't had any problems, and don't expect too. Most guys in the lawn care industry run Saber at 80:1 because of cost efficiency, and the fact that they only have to carry one mix. Go over to Lawnsite.com and read about it if your interested.

treefarmer391 · May 26, 2010

We run all our STIHL here on the farm (028 Super chain saw, FS76 Brushcutter & BR340 Backpack) at 25:1 using non-STIHL oil as the mfg recommends in each owners manual. Dealer says they all can be run at 50:1 like their newer '4-strokes', but that seems a bit lean to me.

They are 20+ years old and have not complained.

Gale Hawkins · May 26, 2010

One shop told me to lower the ratio in hot weather when working them hard so they run cooler.

As noted there is no such thing as 40:1, 50:1, 100:1 oil per say because that value is determined at the time of mixing.

Since we use Super Tech Outboard 2-Ccel TC-W3 engine oil in the diesels and sometimes gas four strokes for fuel system lube I am thinking of mixing it 32:1 and using it in everything.

All gas I bring home for storage is non ethanol 93 octane and treated with Sea Foam at the pump due to it being used mainly in small engines.

J_J · May 29, 2010

http://www.utextension.utk.edu/publications/spfiles/sp268-I.pdf

Read especially the last paragraph.

This tells me that the one-mix oil as designed is sufficient when mixed at 2.6 oz to one gal of fuel, that that is enough oil to properly lubricate the engine.

I used the one-mix fuel for about 21 years, and I don't remember any engines damage cause by this ratio. Some of you say that more oil makes it better, for what. Are you trying to out guess the engineers who have done a whole lot of testing.

Even the 100 : 1 Amsoil oil is mixed at 2.6 oz per gal of fuel.

AMSOIL - Saber? Synthetic 100:1 Pre-Mix 2-Cycle Oil (ATP)