40:1 fuel mix in a 50:1 engine

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I just got a Poulan Pro leaf blower that requires 50:1 mix. My weedwacker is a 40:1 mix so I used the same fuel in the leaf blower until I buy a separate container.

There was no smoke or strange behavior. Is the worst thing that can happen a prematurely fouled plug? Or am I looking at a pending catastrophic engine failure?
 
I mix my sthil 50-1 oil at 40-1 use in all my equipment,weed eater,blowers, chain saws. No problems in years using it.
 
I have l let my Husqvarna 125B blower idle out an entire 15 ounce tank of fuel that was mixed at 32:1 and it didn't even come close to fouling a plug. These modern JASO FC/FD oils are simply amazing.
 
I do it all the time. My wife is using the Covid time to build a new patio/sitting area out back. We have a push leaf blower, but to get in the nooks and crannies, I just bought her a Poulan Pro PRB26 for Mom's day. She loves it. I added the 40:1 and she fired right up (the leaf blower, not the wife).
 
No problem - in fact it will be beneficial if you tune the carb properly to take advantage of the new ratio.

If you do = cooler running engine with more power.
 
Originally Posted by CT8
More oil is better.

To a point. I think the trade-off is fouling of the plug and exhaust if too much oil is used.

I use 32:1 for everything. I haven't had any fouling problems over the decades. Find a decent way to measure so you don't up with some extreme mixture.

One colleague tells me he just throws a splash of oil into the gas with his calibrated eye. This may explain why one 2-cycle mower I bought had to have the carbon chipped out of the exhaust to get it working again.
 
40:1 is fine -- done it a lot when all that was available at the gas station was no-name 2 cycle oil. The rest of that unit will likely fall apart before the bottom end wears out.
 
Better too rich than too lean. I keep 40:1 mixed up for my saw and 50:1 for my blower because its what they call for. I use ethanol free gasoline.
 
There are many factors behind the lifespan of a two stroke engine. Oil ratio being one of them, more is absolutely better, with a few qualifications. It must be a quality oil, jetting and timing must be correct and quality fuel of sufficient octane must be used. Even mild detonation can greatly shorten the life of a two stroke.

The other aspect of a two stroke engine is component and build quality. The Poulan leaf blower uses a consumer grade engine, even with the use of plenty of oil, good fuel and proper jetting, it's lifespan won't match that of a professional grade engine. My 20 year old Echo is still running perfectly, even with a great many hours of abuse.
 
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40;1 will be fine .Run it and forget about it.
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The Toro dealer that sold me my snowthrower said that even though the manual says 50:1 mix is needed (and that's also stamped on the gas cap), he'd recommend using 40:1.

18 years later the thing still runs like a beast.

Don't worry about it.
 
One of the other times this was discussed on BITOG a landscaper claimed he ran 100/1 in some equipment. I`v had no problems with 50/1 in the Sthil equipment and 40/1 Yamalube in an Echo 750EVL chain saw.
 
I'm that reckless soul running TCW3 at 50:1 in all of his OPE regardless of what it calls for ratio wise and I have never had any issues.. You will be just fine. Stihl and Poulan chain saws, Husky weedeater and Hitachi leaf blower.
 
Originally Posted by nwjones18
I'm that reckless soul running TCW3 at 50:1 in all of his OPE regardless of what it calls for ratio wise and I have never had any issues.. You will be just fine. Stihl and Poulan chain saws, Husky weedeater and Hitachi leaf blower.


+1
 
I run 40:1 in everything, including my Hitachi leaf blower that calls for 50:1

I mix the oil with E10 premium unleaded, this seems to substantially reduce the smoke and oil smell and the engine starts way easier when cold

I took the plug out this spring to replace it and it looked great, almost no deposits
 
All my stuff calls for 50:1 but 40:1 is fine (even says so in the manuals)... I use pre mixed gas such as tru fuel.. never ever an issue and my equipment runs much better than on gas I mix myself. I'll never go back to mixing my own gas (unless I were to own a business or something)
 
I use the ethanol free premixed Tru-Fuel product and alternate back and forth between 40:1 and 50:1. I cannot say that I've noticed any difference with any of the four pieces of equipment I own. My first 2-cycle motor was on a circa 1985 Lawn Boy mower that called for 32:1. My nose can certainly tell the difference between that and the more modern ratios, that much I am sure of.
 
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