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2-stroke fuel mixture

EliasMcDaniel's Avatar

Join Date: Apr 2013
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07-14-17, 07:23 AM   #1  
2-stroke fuel mixture

I have a string trimmer that runs on 50:1 gas/oil mixture, and a blower that needs 40:1.

The blower might use two tanks of fuel a year, while the string trimmer probably goes through two gallons.

Instead of keeping two separate cans - with the 40:1 probably going "stale" before it's empty, how much harm would it cause on the blower to run a 50:1 mix?

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pugsl's Avatar
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07-14-17, 08:36 AM   #2  
May foul plug but I don't think it will effect it.

Bud9051's Avatar

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07-14-17, 09:07 AM   #3  
Wouldn't 50:1 be less oil than 40:1?

If my thinking is correct?? I would keep 50:1 on hand and work out how much oil would be needed to make it 40:1. I used to keep a plastic see through oil container around so I could custom mix for different engines, only what I needed.


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07-14-17, 09:14 AM   #4  
You would b better off using the 40:1 mix in both since it has more oil, unless both tools are high end products they would benefit from the extra lube. Have a good one. Geo

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07-14-17, 09:17 AM   #5  
I agree with geo, I'd run the 40:1 in both if I was to only have one mix. It's better to have too much oil than not enough!

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07-14-17, 03:22 PM   #6  
I run all my two strokes on the same ratio with Stihl HP Ultimate oil. Even the really old stuff that calls for 16:1 is still running strong. So, I wouldn't hesitate running one lower oil fuel if using a quality synthetic oil but if you're using a traditional oil I'd run the higher oil ratio in everything.

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07-14-17, 07:14 PM   #7  
would also just run the most common 50:1 with a good quality oil, to lean of fuel mixture is what most often causes engine damage to air cooled two strokes if the engine isn't getting enough fuel do to carb, vacuum leaks or other issues really wont matter if your using 40 or 50 to 1 the oil wont be getting to the engine anyway so damage is likely to occur.

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07-15-17, 05:42 AM   #8  
I use universal synthetic 2 stroke oil in all my 2 stroke equipment. It is good for all 2 stroke engines and all ratios up to 50:1. Everything runs great, I never had an issue, it is widely available, and you only need to keep one tank of fuel.

I have used both Stihl and Arnold (MTD)

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marbobj's Avatar

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07-18-17, 03:44 AM   #9  
If you're talking about the same in everything, I would use the 40:1 mix, especially for hot weather running.

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07-28-17, 03:36 PM   #10  
I have been using AMSOIL 100:1 in two-stroke engines for years and it works fine. It runs cleaner and I've never found carbon in the exhaust.

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