How to modify gas to oil ratios

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

genesis5521

ArboristSite Operative
Joined
Nov 28, 2009
Messages
455
Reaction score
90
Location
Northeast Wisconsin
I just bought a new toy (gas trimmer) that requires a 40:1 gas to oil ratio. All of my other tools use a 50:1 mix and it's always pretty fresh cause I use it a lot. I won't be using this new toy a whole lot and didn't want to mix up a separate batch that would just go bad over time. So I made up a chart indicating how many drops of oil I need to add to my 50:1 mix to get a 40:1 mix. I'll be using just 8 ounces of gas at a time, so according to the below chart, if I start with 8 ounces of my 50:1 mix and add 26 drops of oil, I'll have a 40:1 mix. Basically, just add 3.25 drops of oil for each ounce of 50:1 gas. Don't worry about the fractions of a drop. Just round things off. Using an eye dropper is the easiest way to do this. Thought this might be helpful to others.

OK. OK. I just retired and have wwwaaayyy to much time on my hands ! ! ! :msp_unsure:

Don <><

attachment.php
 
Last edited:
The general consensus is that 50:1 is fine to use in any 2 stroke.

That being said, I run closer to 40:1 in all of my stuff. Sure it may smoke a little more, but it's more tolerant of lean conditions, or bad measuring and mixing. At least that's my theory. :)
 
I'm the OP. I suppose you guys are right about running everything at just one ratio (Say 40:1). But then the perfectionist in me wouldn't let me sleep at night. Then I'd have to start drinking again to get to sleep. :( And it's no big chore for me to do this. But to each his own I guess. I'll only be using this thing like once every 2 or 3 months for maybe 20 minutes at a time and only during the summer. That's just twice a year and 40 minutes of annual run time. I hate to make a special batch just for that.

Don <><
 
Last edited:
I'm the OP. I suppose you guys are right about running everything at just one ratio (Say 40:1). But then the perfectionist in me wouldn't let me sleep at night. Then I'd have to start drinking again to get to sleep. :(

Don <><

Whatever works for you. :) If it were me, I'd just get a small gallon gas can from walmart, and make a 40:1 mix in that. Then mark it as trimmer. Anything left over at the end of the season can go in the car, or get used up in the saws.

Mixing oil every time you want to use the trimmer will get old, and you'll have things like, a half a tank of fuel to deal with.

Just some thoughts. I've been there. Now, I use the same mix for everything.
 
FWIW when running saws for limited work I mix a qt. at a time using an empty tru fuel can , and the mix miser syringe.

Some tools , like the one used for the gawdawful job of weed whackin get straight trufuel all the time ,that job is miserable enough without messin with mix.

Works for me.
 
All my stuff was 40:1 except the Husky 142 which was 50:1. I had a separate 1ga jug for that. Yesterday the remains of that got poured in the tractor and now it's 40:1 too - after all, previous versions of that saw were 40:1 and it's the same darn engine as is used in a lot of other saws at 40:1, including my 2775. I think mixing in the tank is a bad idea - just too easy to screw it up.
 
Hey Don, great chart. You wouldn't happen to be an engineer of some type would you? It looks like a product of engineer thinking, and that is not meant to be an insult, it's just how engineer types think. I guess I fall in to the keep life simple category. I run 50:1 Stihl Ultra Synthetic in all two cycle equipment at my place, All saws, including old blue Homelites, Lawnboy mowers, trimmers, blowers,etc. Have had no problems with any of them so I guess it is OK.

Steve
 
Sounds way to complicated to me, and I guess I am way to ADD to count out how many drops I dropped in, sure as shootin a squirrel would go racing by the second I was half way through the counting process, and I would have to dump the whole works in the truck and start over again.
Me, I got several tools that take the 40:1 ratio and many 50:1, and they all feed out of the same fuel jug. I dump one can of oil in, and add 4.5 gallons of fuel in, and call it good. Considering the weedeater that is supposed to have 40:1 has been eating out of that jug for six years now, I reckon its getting plenty of oil. And none of the 50:1 saws have complained about the extra oil either.

Life is to short to fool with eye droppers.Slosh some oil in there and get to work.
 
I'm the OP. I suppose you guys are right about running everything at just one ratio (Say 40:1). But then the perfectionist in me wouldn't let me sleep at night. Then I'd have to start drinking again to get to sleep. :( And it's no big chore for me to do this. But to each his own I guess. I'll only be using this thing like once every 2 or 3 months for maybe 20 minutes at a time and only during the summer. That's just twice a year and 40 minutes of annual run time. I hate to make a special batch just for that.

Don <><

Well, that's fun doing it that way..but...just run your normal 50:1 for everything else, and buy a quart can of premix at 40:1 for the trimmer, if you really really want 40 to 1. The canned fuel is good stuff, seals back up good, and lasts a long time. You won't use much so the price of a quart at a time isn't that bad.
 
Lol @ adding 3 drops of oil to your gas mix. :)

I just mix my gas rich and run everything 2 stroke on it. About 35:1 usually. :)
 
Man,

Now I've got to go tell that McCulloch 1-72, Homelite Super 1050 Auto, both McCulloch Pro Mac 1000's, The Pioneer 1110, that I is sorry. Been running the wrong mix in em. Not to mention them half a dozen XL-12's.

No wonder I ain't been sleepin well.

:rock:
 
Wow! Thats all I can say. Your trimmer will never know the difference if You run it at 50:1 just like all your other stuff.
 
Back
Top