Question about two stroke oil

reynoldston

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Wow, thanks for the history lessons in 2 stroke oil. So they actually came out with the engines before the 2 stroke specific oils to use in them? Well, on second thought I guess that makes sense. Just out of curiosity what happens if you run a higher oil content mix than required, i.e. 40:1 in a 50:1 motor? Will it just not run as well and foul the plug or will it likely damage the engine?

40:1 or 50:1 I can't see where it would make any difference. Now if you get it down say to 20:1 it would just foul your plug and if ran for long periods you would get a lot of carbon build up and problems like carbon on the piston hitting the head. The company that made and design the engine knows what oil to use and how much and for what it cost why not use the right oil and amount?
 

oldyellr

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Probably wouldn't make a difference in a low performance application like a lawnmower. Most of my 2-stroke experience is from racing motocross and snowmobiles in the 1960s and '70s where I holed my share of pistons.
 

wildbill

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Once upon a time, in the mid 80s, I had a 1971 100hp Johnson outboard. I was under the impression that a richer mixture of oil-gas, the more oil the better off the motor would be, was the way to go. One day the motor started missing, thought it was a fouled plug.....not. I had to pull the motor apart due to almost zero compression on one of the cylinders. I found all the pistons were a total gummy mess, rings stuck, etc. So, I cleaned everything up,:ashamed: replaced the rings and all was well. But, the a well respected boat mechanic told me 50:1 ratio was only needed at high speeds, and that at low and trolling speeds the motor did not need even half that. So, what I was doing was killin' my motor with that 'extra' oil richness instead of helping it. An expensive lesson......
 

oldyellr

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Well, back in the day when I had my first outboard (late 50s - early 60s) I remember a ratio of 1:16 being common. (Well, before that, when I was into model airplane engines I remember 1:3.) Anyway, I thought I was being adventurous using Mercury oil that was mixed 1:32. Then came 1:50 and eventually 1:100. Of course, the engines improved greatly over the years, going from plain bearings to needles and rollers and better piston alloys, as well as better oils.
 

wildbill

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We are probably close to the same age, me 63. Dad had a service station about a mile from Watts Bar Reservoir, Tennessee River. 'Bout '59 through '65 I also well remember putting MANY cans of 30w oil into MANY 6 gallon gas cans for the boats stopping in. Best I remember everybody wanted a qt. of oil to the 6 gallons. That same 30w we also put into cars. I remember one dude always had his own oil for his boat, said it was special made for his engine..............:biggrin:
 

Oddball

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We are probably close to the same age, me 63. Dad had a service station about a mile from Watts Bar Reservoir, Tennessee River. 'Bout '59 through '65 I also well remember putting MANY cans of 30w oil into MANY 6 gallon gas cans for the boats stopping in. Best I remember everybody wanted a qt. of oil to the 6 gallons. That same 30w we also put into cars. I remember one dude always had his own oil for his boat, said it was special made for his engine..............:biggrin:

WildBill, you're showin' yer age there ole timer! :wink: You've got me by 17 years. What a difference a generation makes sometimes. Or sometimes not even a full generation. I don't think I ever remember hearing of a two stroke engine until I was well into my teens. We always had four stroke mowers, the only engine powered equipment we suburbanites needed back in the day, other than a car. If we wanted weeds cut or lawns edged, we broke out the clippers, scythes and hand push edgers. We never had a boat, but my best friend's dad did. It had a 40hp outboard Evinrude, but it was a four stroke also. At least I assume it was. I was with them on it a lot and never remember his dad mixing oil in the gas tank.
 

oldyellr

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WildBill, you're showin' yer age there ole timer! :wink: You've got me by 17 years. What a difference a generation makes sometimes. Or sometimes not even a full generation. I don't think I ever remember hearing of a two stroke engine until I was well into my teens. We always had four stroke mowers, the only engine powered equipment we suburbanites needed back in the day, other than a car. If we wanted weeds cut or lawns edged, we broke out the clippers, scythes and hand push edgers. We never had a boat, but my best friend's dad did. It had a 40hp outboard Evinrude, but it was a four stroke also. At least I assume it was. I was with them on it a lot and never remember his dad mixing oil in the gas tank.

Wow! I guess at 70 I'm a really old fart! Back when you thought outboards were only 4-strokes, I thought 4-stroke outboards were a novelty. Very heavy, low performance, expensive and complicated. Nothing you could rebuild out on the lake with tools in your tackle box. I still have a boat with a 1969 Merc 650 (the good ones with 4 cylinders, not the new 3-cylinder ones) on it and you mix the oil with the gas. I guess the next generation won't even know what 2-strokes are. So sad.
 

wildbill

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Drop the 'r' in the descriptive word to an 'ah', its gives it grace and wisdom. (faaht) It would be a Boston type of 'r'.
:smile:
You being 70 is cool! I only hope I can still ring in as well for years to come. :wink:
 

wildbill

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My Dad purchased a Sears lawnmower in 1954, and it was a 2-stroke, 18" cut. We had a 1/2 acre yard and that's aot of laps with 18". The mower finally croaked about 1966 due to needing rings which could not be found at the time. :smile:
 

oldyellr

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It wasn't too long ago (at least in my time scale) that 2-stroke push mowers were still sold. They were the cheapest ones. I guess it was environmental concerns and dumb people forgetting to add oil to the gas that finally led to their demise. It's interesting that most weed whackers are still 2-stroke. Four-strokes will never equal their light weight and power/weight ratio.

And since this thread is about 2-stroke oil, I have an interesting story. Back in the day, a friend of mine used to road race a Manx Norton. Back then the ultimate racing oil was Castrol "R", the main ingredient of which was castor oil. It was quite expensive, about $4/quart (cheap motor oil was 40 cents). After he drained the oil from his Manx at the end of a day of racing, he used it in the gas for his 2-stroke lawn mower. When he cut the grass, the whole street was bathed in the sweet aroma of "R".
 
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