Fuel mix ratio

[bmwpower]

Would you agree with this response to a question regarding what fuel mix ratio to use for a chainsaw?

This Unit Does Use 2 Cycle Oil. The OEM Suggest Starting with 32:1 Ratio and Decreasing the Oil Ratio if the Engine Smokes a Lot or if Excess Oil Runs Out of the Muffler During or After Use. However, All Two Stroke Engines will use a 50 to 1 Ratio using Today's Two Stroke Oils. I once used an Old Chainsaw probably from the 1960s, that had a sticker on it that said to use a 25 to 1 Fuel/Oil Ratio, but that would have been using Two Stroke Oils of the Time Period the Chainsaw was Manufactured. In that Chainsaw I used 50 to 1 Ratio with no problems. Today's Two Stroke Oils compared to Yesteryears are more Efficient at Lubricating. It is like comparing Today's Synthetic Motor Oil to Motor Oils of Decades ago. All the Equipment I use in Landscaping, anything from a Weed Eater, Leaf Blower, Chainsaw, Hedge Trimmer, use 40 to 1 ratio, and I use all types of makes and models, Stihl, Homelite, Husqvarna, Shindaiwa, and Echo, Sears. I mix up a 5 Gallon Fuel can and use it in all of the Equipment for my Customers and for my Landscaping. I like my Fuel/Oil Ratio a Little Heavy, so I use a 40:1 Ratio.

 

[nissan_crawler]

*pour dab in bottom of one gallon can* "ehhh, a little more" * pour another dab* add gas, shake

yes, that's how I do it, I know I'll catch flack for it. I have yet to have an issue in 20 years, though...

I run 25 year old synthetic two stroke oil.

 

[nate379]

I put a 1/2 quart in 5 gals, so 40:1.

 

[bmwpower]

25 years old??? Damn.

I'm running new stuff.

My saw supposedly takes 40:1. Chainsaw shop guy who seems to know his stuff said to use 50:1 and handed me a bottle of Echo oil.

I just don't need any more problems this weekend. If I blow up my saw I will probably just end it all....

 

[nate379]

I'd rather run it rich than lean. I have my equipment tuned to the mix I run though. I don't use synthetic stuff, just the Walmart Outboard oil that is around $10 a gallon.

 

[35mastr]

I use 40 to 1 in all my equipment. Use a ratio cup. Been doing it that way for 20 plus years in motorcycles and equipment and never had a failure.

 

[bmwpower]

Ok, so if I want to make 40:1 mix from a bottle measured for a 50:1 mx...

Just add 0.8 gallons of gas instead of 1 gallon, correct?

 

[nate379]

3.2oz to a gallon.

 

[bmwpower]

3.2oz to a gallon.

I don't have that luxury. I've got a small bottle of oil meant for 50:1.

 

[nissan_crawler]

Ok, so if I want to make 40:1 mix from a bottle measured for a 50:1 mx...

Just add 0.8 gallons of gas instead of 1 gallon, correct?

correct...

 

[bmwpower]

Thanks...it's been a long night...

 

[Red Green]

If I care about it I run what the recommended ratio is. I have a Mac 1-41 from the early sixtys that my grandpa bought new and I still use. It gets the recommended 32:1. It doesn't seem to smoke or have oil leaking out of the muffler.

 

[06jds377]

I work with outboards a lot, and I can honestly say I've not seen anything newer mix anything richer or leaner than 50:1 at WOT. I also agree with the oil properties statement in general, of course, there will be exceptions.

I'd say this crosses over to any modern 2-stroke engine.

That said, I don't think anyone wanting to run 40:1 will do any damage. Of course, I'm taking no liability here.

 

[ryno]

it really depends on if your using a synthetic or petroleum blends.
full i don't see any problem running it 50 to 1
if its new id run 1/2 a tank or so at 32 to 1 to help break it in.

 

[nissan_crawler]

25 years old??? Damn.

It's wicked stuff, they quit making it 25 years ago or so. Dad had a 6' stack of cases of it in the shop. It was mainly for our sleds, but works great on everything. No plug fouling, no smoking, no carb gumming.

 

[Here2Learn]

"I'd say this crosses over to any modern 2-stroke engine."

I hope you are talking about outboard engines, as that won't last too long in small - bore off-road bikes. I'll stay away from commenting on kart engines.

In older bike manuals, ratios such as 20:1 or 24:1 were listed. As oils improved, the ratios went higher.

 

[njfl]

"I'd say this crosses over to any modern 2-stroke engine."

I hope you are talking about outboard engines, as that won't last too long in small - bore off-road bikes. I'll stay away from commenting on kart engines.

In older bike manuals, ratios such as 20:1 or 24:1 were listed. As oils improved, the ratios went higher.

X2

You're better off erring on the oil-rich side (like 40:1 or 32:1) rather than 50:1 as long as your spark is strong enough to fire in it. Two strokes are meant to burn oil.

On a separate note, I run castor oil (Maxima 927) in my two-stroke standup jet skis. When I pulled my motor apart the other day after running two years, I was amazed at how clean everything was inside. castor smells great too.

 

[Sloper0204]

If you want to get real technical about how to mix and jet your saw, you'll need to do a few things.

First, buy a Ratio Rite.
Second, read up on jetting for your saw.
Third, start reading your plug and piston wash.
Adjust accordingly.

Always start rich and lean out, a two stroke runs its best when its right on the verge of squeaking a piston.

 

[Mark-in-NH]

*pour dab in bottom of one gallon can* "ehhh, a little more" * pour another dab* add gas, shake

yes, that's how I do it, I know I'll catch flack for it.

you won't catch any flak for it from me because I do pretty much the same thing. I buy my 2 cycle oil in large jugs. The tiny bottles are to costly and are a hassle.
My Husqavarna backpack blowers are a 50:1 mix ratio. It's printed / molded right into the fuel cap. Since they are what I use the most mixed fuel in, thats is the mix I run in everything. But since I use the "Nissan_Crawler mix method, my mix is only 50:1 +/-

 

[babzog]

I had a trimmer which burned itself up due to too little oil in the mix (or possibly the use of more highly ethanolized gas)... it lost power as it warmed up till she just quit. Cylinder was ruined - scored beyond belief. Possible that some foreign object got in there but the BIL who looked at it said the damage was due to improper mix, overheating, parts coming apart, etc. "Mix 'er till she smokes." is what he told me.

The proper mix ratio is usually printed on the gas cap or somwhere on the machine. Personally, I use a good 32:1 mix on all my gear (some of which is stated to use 40:1). Since I don't want to have to remember which can contains which mix, I just mix to the lowest common denominator... worst that will happen with a richer mix is the plug fouls (which hasn't happened).

Seems that newer equipment is using less oil than the older. I've also observed that heavily abused tools like chainsaws use more oil in the mix than lighter duty tools such as trimmers or leaf blowers.

I have a little plastic measuring cup (got a package of them at CT Boutique for a dollar a few years ago) that I use to measure out the oil for the gallon of gas. Far easier than fiddling with the bottle.

 

[nate379]

How much is in the bottle? I get my oil in the gallon so it's an eyeball for a quart in a 5 gal. It's just a chainsaw, not a NASA moon buggy I figure.

I don't have that luxury. I've got a small bottle of oil meant for 50:1.

 

[IDASHO]

Mower is 4-stroke, garden tractor is 4 stroke. So they get the straight stuff.


Weedeater takes 32:1, chainsaw is supposed to take 50:1. Ive already got 2 cans of fuel, straight and mixed. I aint mixing another batch, and keeping another tank around, so the saw gets the 32:1.

Little less power, a little more smoke. but it will NEVER run too hot or with too little oil. I can deal with that.

 

[Toolhorder]

The weed wacker I have is 40:1. I usually throw in a little more oil as I don't care about smoke. I have two vintage Yamaha RD350's and if it ain't smokin it's broken. Both my bikes are oil injected but the newer Yama-lube I use in them produces little to no smoke through the engine which is disappointing...
I personally love the smoke.