How precise is your fuel mix?

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sofasurfer

sofasurfer

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michigan
When mixing fuel how precise are you?
50:1 uses 2.6 ounces to a gallon. Do you use 2.6 or round off to 3 ounces?
40:1 uses 3.2 ounces. Do you use 3.2 or round up to 3.5 or 4 ounce?
Does using a little extra lessen performance?
 
Chevboy0167
Joined
Nov 28, 2020
Messages
1,509
Location
Iowa
Most users of "newer saws" and some older ones prefer the 40:1 or at least something below the recommended 50:1 to provide a bit more oil in the fuel mix to lube up all the bearings in the crankcase.

Reason? Saws are getting lighter which is a good thing for weight savings and less fatigue for long time usage. Downside is more plastic where there use to be all metal parts. This includes the crankshaft outer bearings. They used to be all metal inner cage that holds the ball bearings in place. Now most are a type of heat and fuel "resistant" plastic inner cage. We all know plastic wears out with age and usage yes?

Many saws have met demise by the crank bearings giving out on even less than 1 yr old saws/tools that were ran with the proper manual stated 50:1 oil/fuel mix as "said by the end user". Even still under warranty. It's even harder on the saw if you mill or use it a production setting as a big wood feller.

I have seen 2 saws so far with the plastic inner cage very loose or broken. So I put replacement steel inner cage in for longer service life and run a bit more oil in the fuel to give the tool a better chance for survival. Retuning the carb for this heavier mix and cutting conditions is recommended of course. YMMV...
 
Woodslasher

Woodslasher

Make McCulloch Great Again!
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Commiefornia
I used to buy the little "makes 1 gallon" bottles of oil before I got a 1 gallon jug of oil. Now I fill up the little bottles to roughly the same level that they were filled to when I got them. If I'm milling, I'll pour a little extra oil in. Otherwise I just get them pretty much to the mark.

None of my saws have complained so far and my dad did pretty much the same thing for 20+ years and none of his saws/blowers/trimmers are scored. FYI, he doesn't tune stuff so if there was any issues from approximating the ratio he would've found out.
 
sundance

sundance

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It’s cheaper to buy mix oil by the gallon to, mix it using the Ratio-Rite then those dinky little mix bottles 😆
I buy mix oil in bulk then use a Ratio-Rite to measure into the little bottles. Makes it handier and don't have to clean up the Ratio-Rite every time.
 

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