two cycle oil mix questions

[alderman]

I've got an old  Homelite xl 12 (big blue) that calls for a 16:1 mix.
My older Shindaiwa machines call for 24:1.
My newer Homelite calls for 32:1.
My Shindaiwa 488 book recommends 40:1.
My newest Shindaiwa blower says 50:1.

My question: Is the ever decreasing oil ratio a result of better technology in the building of two cycle motors or is it due to better quality in the two cycle oils?

I have been running 32:1 Shindaiwa mix in all my older Shindaiwa machines and I have found them to be running better than ever.  Am I making a mistake by doing this or should I stick with the 24:1 ratio and continue to clean the spark arrestor screen?

Thanks for any input for one of the more mechanically inept. :P

[twoodward15]

My buddy thought he was mixing his oil right for his shinnys and when he finally really read the bottle he'd been running close to 60:1 for about 15 years now.  Those saws really run well like that.  He said they haven't had any problems, so why change.  man those saws scream with so little oil in them!!!!  Id definately keep running 32 to 1 oil and not worry about it.

[StihlDoc]

The technology has improved in the machines but better research and understanding in two stroke oil formulations is the primary reason that you can run leaner oil mix ratios. Running rich oil mix is an old habit carried over from the past when sometimes it was necessary to run richer ratios to keep the engines "alive" with the old oil formulations, before there were any industry standards for air cooled two-cycle mix oils. There are now high tech additives used in air cooled two-cycle engine oils and internationally recognized performance standards for these lubricants. These modern oils mixed at a 50:1 ratio provide bettter protection (and detergent additives) than old formulations that were mixed at richer ratios. Mixing at richer ratios will lead to combustion deposit build-up. The deposits are very abrasive and any build-up in the exhaust port can cause ring wear and piston scoring and restrict spark arrestor screens. Richer ratios can also lead to deposit build-up on the crankshaft bearings and connecting rod bearings. The deposits act like fine sand inside the engine. This damage occurs over a long term since it takes many running hours before the amount of deposit build-up becomes a problem. I have analyzed many engine failures caused by mixing more oil in the fuel than recommended.

[rahtreelimbs]

Richer ratios can also lead to deposit build-up on the crankshaft bearings and connecting rod bearings.

While this may be true with the dino oils, the newer 100% synthetic oils eliminate this problem!!!

[minesmoria]

Amsoil oil is synthetic , way better than still dino oil?

[rahtreelimbs]

For the price, Mobil 1 MXT2 is the only way to go. Easy to get at Autozone.


A lot of guys use this oil with outstanding results!!!

[Lewis Brander]

Hello. My saws call for everyting from 10/1 mix for some of the older saws to 40/1 mix for my newer saws. I run a 32/1 mix for them all and have had no problems. If I'm going to really work my older saws (demonstrating them and not just starting them and running them) I will run a richer mix of around 24/1. I use the MX2T Mobil Synthetic Oil and love it. Just decide what mix you want to use. Make sure you adjust your carburetor for that mix and you should have no problems. Running the old saws at 16/1 mix, I've had no promlems fouling plugs or any carbon build up using the synthectic oils. Course I run Mobil 1 in all my vehicals and 4 cycle engines also. I swear by the stuff. Take care. Lewis.

[tony_marks]

another mx2t advocate. but to be honest i didnt have any with me so put husky oil in at about 40-1 . ill use it up ,as its doing real good. so good its got me thinking about a syn dino mix using stihl husk or echo. but definitly 3/4 mx2t.. this at 35 -40 to 1. the dino oils tend to foul at richer mixstures ,for me . while mx2t ,i think could be mixed as rich as u wanted to go ,within reason.. good stuff,but not the only thing that will work well.

[Blake22]

I use husky oil mixed 40-1 in everything, saws, blowers, trimmers, golf cart & I've never had a problem. I'm sure the synthetic is better but if it ain't broke...........

[Chris J]

Hasn't MX2 been renamed?  I can't recall  >:( the new name.

A saw builder (klicktosacket, don't know if he still posts here) on another site recently tested one of the amsoil oils, & wasn't happy with the build-up on the piston rings.

[tony_marks]

yes they changed the name to racing oil mxt or something like that. ive got a case of it when it was called mx2t.. good stuff,what ever they callit.