converting 40::1 to 50:1

[Shrubitup]

Originally Posted By: Finz
Originally Posted By: Srt20

One more BTW, the 2 stroke oil that I use in every engine is $15 per Gallon.



Which 2 stroke are you using?


Not judging or insulting but prolly TCW3. That's a low price! I pay about double that for "lesser" motorcycle related smoker oil.

 

[cpjr]

I think I will just run the 40:1, based on what you guys are saying, there is so little difference between the 40:1 and 50:1, I doubt the trimmer will know the difference !! Besides what damage could a little extra oil do Manufacturers probably went with 50:1 for CARB compliance anyway. I not sure that if a warranty repair had to happen, anyone would be able to tell that 40:1 was in place of the 50:1

 

[Srt20]

Originally Posted By: Finz
Originally Posted By: Srt20

One more BTW, the 2 stroke oil that I use in every engine is $15 per Gallon.



Which 2 stroke are you using?


I use Mystic 2stroke oil. It is available in tcw-3 or not. Normal price is 21.99, on sale every 3 months at 14.99, and very so often (maybe 6 months?) mail rebate $7 off per gallon, equals $8 per gallon. That is for full synthetic. Synthetic blend is $2 cheaper across the board. Blains Farm and Fleet, midwest chain, but obviously Mystic is available throughout the USA.
I usually buy 6 gallons at a time, once a year.

It's a very good oil, as are most 2 stroke oils. I've used it for tens of thousands of miles in high hp snowmobiles as well as OPE, and every single 2 stroke engine I own. I've used both TCW-3 and not with no issues either way. One engine is 14.5-1 compression ratio, and another is 13-1 compression ratio. The rest are all stock, or close to it.

 

[linksep]

There is a 99.9999999999% chance your carb is tuned to run 50:1 with the "50" being E10 or E15 gas. E = dollar-bills with almost no nutritional value to your engine. So rough estimate E10 gas at 50:1 is darn near equal to E0 at 45:1. Pretty freaking close when you're talking about mixing up 1 gallon of gas (typical fuel can for residential 2-stroke OPE)... The difference is about 1/4 oz of oil in a gallon. This isn't rocket surgery and I'm not busting out NIST certified lab-grade graduated cylinders to mix my 2-stroke fuel. The only way I imagine you would be in danger of ruining your engine would be if you used E10 (or E15) at 40:1 under heavy load for multiple full tanks of fuel in temps under 40 degrees F. (E= leaner A/F ratio, 40:1 = leaner A/F ratio, cold weather = leaner A/F ratio; add them up and you could be in trouble, remove one or two of those factors and you're probably fine.)