2 cycle questions (oil mix)

[dodge trucker]

I have 2, 2 cycle Tecumseh engines, on some weird "Flymo" mowers./// and sometimes borrow a 3rd, that one on a post hole auger.
The shroud is a slightly different shape on the newer Flymo, I absolutely cannot find any identifying numbers for the engine. I think its a "TVS" series.
the older one and the one on the auger look identical, and are "AV" series.
The "AV" ones have diaphram carbs, the TVS has a float carb. The AV's want 24:1 the TVS wants 32:1. Will I hurt the 24:1 versions if I run the 32:1 mix in them?
I notice that some of the "pre mix" cans at the store lump 40:1 and 50:1 machines together, and have an "all in one" that covers either 40 or 50:1. I'm not sure what they actually set the ratio at, on that gas. Now I know better than to try a 50:1 mix in a 24:1 machine. I remember that "opti mix" /which I never used,// that claimed to cover "any" mix ratio with universal proportions. I dont think they sell that stuff anymore, The Lawn Boys I have had over the years took a 32:1 mix, if Im remembering right (its been a while)

 

[Lance Skene]

I always run a heavy mix even at the landscape company with all their Stihl equipment... you cant hurt anything with too much oil, it will just start to run crappy and foul the plug early... but you can hurt an engine if its too lean on oil. Modern oil do work better than what was available say 30 years ago but the engines also have more wear than when they were new... I would suggest trying the 24:1 mix in the 32:1 engine and see how it runs.... that would be safer than going the other way around.

 

[chieffan]

I agree with Lance. Better to be to rich on oil than to light. Poulan built chain saws for Sears for many years. Poulan engines used 50:1, but Sears says to use 40:1. I think the only reason Sears says 40:1 is warranty escape.

 

[ol' stonebreaker]

I had a '53 Evinrude that said 24:1 but always ran 40:1 with no damage after many hrs of trolling and 1/2 throttle. Same for my Tecumseh on the post hole auger. YMMV. On ones with a spark arrestor too much oil will eventually plug the arrestor.

 

[Toomanytoys84]

I usually run everything 40:1. The old butter cup lawn boys have been running with that mix for years now.


The oldest lawn boy with a D400 Pre-1972 is suggested at 16:1. My grandfather always added 30W oil to his gas to run his lawn boys. These new synthetic oils allow for a much leaner mix.

 

[dodge trucker]

Yup I remember the old Evinrude we're all 24:1
There's a '53 model 7-1/2 HP in the garage my dad bought in the mid 70s that my brother and I both want. Dad's gone, it'll sit there unused til mom goes whenever that might be

 

[Lance Skene]

You can get away with running the oil low on the dipstick in your car/truck also.... but would you??

Manufacturers may claim the new synthetic oils allow for as a leaner mix but I tend not to believe everything I see in advertising.

 

[dodge trucker]

In this case I was wondering if there's really a difference between the engines where one would need more than the other? Same kind of mower, both Tecumseh 2 cycles, plus the auger has the same exact engine as the older mower. Im wondering why the difference in specs for mix ratio between them?
If one was a Clinton or Briggs or "some" other brand I could make more sense of it.
Is it a difference in the engines, or a difference in specs because of "advancements" in oil tech, or an EPA driven thing? Should they really all be running the same ratio? Is it a difference between some models having a diaphragm carb and the other a float carb maybe?
I know at work they've gotten rid of the older 2 cycle stuff, everything there now calls for 50:1 but in the flammable cabinet there's still (now empty) cans marked with 16:1, 24:1, 32:1 besides the 50:1.