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Techniques for 2-cycle engine tools

Don't laugh, but what are some of your gas handling & storage tips for garden/lawn 2-cycle engine tools ?

Here's my inventory that was recently purchased:

Snow Blower with 4-cycle engine (Craftsman 26" 2-stage).
Stihl Leaf Blower, 2-cycle
Weed Wacker Trimmer (Craftsman), 2-cycle
NO Lawn Mower (wife is afraid I'll die mowing as our land is down slope).

I use a 2-gallon gas "rated" jug to buy the gas. After that, I've been estimating the 40-1 oil/gas -- not a good aproach.

Do you pre-mix a gallon (40-1, ex-water gallon jug) or mix fresh batches using a measured amount of oil ?
Do you drop in gas stabilizer during the 1-month stored gas is fresh ?

(I lived in high rise apartments in Manhattan, NY during the first 40 yrs of life, then 7,500 sf of flat, maintained soil in Silicon Valley where plants sleep only 1 month in the year & where I didn't need power lawn tools. Now, I have 1/2 acre of Cambodia jungle land, big bugs, snakes & humidity near CIA). Langley.)

A. Spruce
Re: Techniques for 2-cycle engine tools

The only thing I've started doing is adding Marvel's Mystery Oil to both my fresh gas and 2-cycle gas. It started several months ago when a friend was having hard start issues with her lawn mower and wood chipper. The chipper, in fact, has needed a new diaphragm in the carburetor every year for the past few years.

I happened to be watching a video on YouTube of a guy servicing a long neglected mower, which is where I got the idea of using MMO. I decided that it was a cheap enough investment to see if it worked. My friend's lawn mower started running smoother and starting easier with each time it was started, which is many time over the course of mowing her very large lawn. The chipper has seen a similar start/run improvement. I've started using MMO in my own fuels as well and have been noticing easier starts with everything.

MMO is also rated to replace a portion of the crankcase oil, which is supposed to help keep things clean and lubed in the bottom end of the engine as well.

As for mixing 2-stroke oil, I purchase the 2.5 ounce mix and add it to 1 gallon of fuel for the proper mixing ratio (as per label ) This is easiest for me, since I don't use large quantities of this type of fuel. What I would recommend for you is to purchase a second fuel can, of 1 gallon capacity, and mark it specifically for your 2-stroke engines. When you purchase fresh fuel, only purchase what you can use in a short period of time.

I've never had a problem with "old" gas, and most lawn equipment doesn't care either. If I know the gas is particularly old or dirty, I will drain the tank and fill with fresh, but if there have been no run or starting issues, then use the old gas up, or add a little fresh fuel to it. I don't use fuel stabilizers, I'm more of the opinion that things should be run regularly, rather than "stored".

Here's the thing, if you keep liquid fuel in your equipment, the seals and diaphragms won't dry out and get hard. The most that is going to happen is some of the fuel volatility will dissipate, which is why you just add a little fresh fuel to the tank and run the engine. The next thing is that you should run engines frequently, I usually try for about once per month. You want to start and run the equipment as it would be under normal circumstances. You want to bring it to full operating temperature and put a load on it if possible (particularly important with generators ).

So, to sum up, I have two fuel cans, one for fresh fuel, one for mixed fuel. I do not use fuel stabilizer, it just isn't necessary. You do want to carefully measure you 2-stroke oil and fuel quantity to maintain the optimal ratio for your equipment. I personally only use Stihl or Echo oils, and everything runs on the same 50:1 mix. Stick with a good quality oil, you'll have better performance with your equipment. Lastly, I am also using MMO in everything, so I add the MMO to the fresh fuel can and then use that to make up the 2-stroke mix.

Re: Techniques for 2-cycle engine tools

I also put MMM in some of my engines. It seems to make my lawn tractor run a little smoother. I add some to the gas tank a few times a year,not every time I fill it up.
I agree with above. I have an extra can for my 2 cycle gas/oil mix. I only mix in small quantities as I don't use this gas as much. (Stihl chainsaw and weedwacker).
I also don't have too much issue with leaving gas in my engines. The one exception is my snowblower. That thing was always a pain to start each fall. I have since run it down each spring,and just make sure I top it off with fresh gas each fall before I fire it up. That seems to have been working fine.

Re: Techniques for 2-cycle engine tools

I think I can tell you how not to do it. For example, about once or twice a year, I use each of the following; chainsaw, mini-tiller, and big tiller. The chainsaw and mini-tiller are two cycle. First I add fresh gas and oil mix, attempt to start, say a few cuss words and attempt to start again. Then it gets personal as I call them names, cuss at them, and threaten them and attempt to start again. Finally I dump out all the gas and rebuild the carburetor, put in fresh gas, start, do the job and then put them up, half full of gas, no cleaning. Next year I repeat all the above.

The big tiller is a 4 cycle so usually its the above steps up to the point where it gets personal, then the big tiller finally succumbs to my threats and starts.

Then there is my weed wacker, two of them actually. One is an 18v electric that is good for light duty stuff. I used to have a Craftsman 4 cycle with 16" wheels and a 5 horse Techumseh engine. That engine was always hard to start and last year is just locked up. Common sense told me to go down the the Northern Tool Supply and get a B&S 6.75 engine. 6.75 what, I don't know but I have had two of them on lawn mowers and they have always been easy to start.

But I saw a brand new Husqvarna trimmer with the 675 engine for $270 and by that time I was tired of messing with the old trimmer. BTW how do they sell a lawn mower for $150 which uses that engine that sells for $170 by itself? Anyway, big mistake. The big wheels on the Husky are only 12" in diameter and I didn't think it would make that much difference, it does. 12" wheels are about 10 times harder to push around than the 16" wheels, who knew.

Anyway, it was hard to start all summer too. I thought that was unusual for that series B&S. Yesterday I took it out of the shed to use for the first time this year and it just would not start. It wasn't getting any gas. I pulled the carb after all the above steps and would you believe, I found a bug in the fuel intake, just above the needle and seat. Cleaned it out, filled it up and it started first pull. It must have gotten in there at manufacturing as that bug didn't get through the filter.

I worked it hard and put it up wet too, but I am counting on the 4 cycle reliability. My 20 horse Murrey lawn tractor with B&S engine has been going strong since 1997 with little maintenance, just annual oil changes (where does B&S get off charging $14 for a cheap oil filter?) and an occasional blade replacement.

Now, I wonder how well an 18v chain saw would do? Maybe one of those new 40v chainsaws? And mantis now has a 4 cycle engine for the mini-tiller.

Re: Techniques for 2-cycle engine tools

It's funny how temperamental some of these engines are,eh?
My 2 cycles,the weedwacker and chainsaw I mentioned above,both Stihl,will start with about 3 pulls even with old gas in them,after sitting for months at a time.
My old chain saw,a Craftsman,would start OK cold,but would NOT start when hot. Even with fresh gas,and no matter how the carb was adjusted,and rebuilds/cleaning made no difference.
I have an old rototiller I bought at a garage sale over 20 years ago. I would guess this tiller is from the 60's and has a B&S engine. I use it maybe once every few years. If there is any gas left in it's rusty metal tank from it's last use,I just start it and it will start on the 1st or 2nd pull every time.
I had an old go-cart for the kids with a B&S engine. Old metal tank. That carb would clog CONSTANTLY with metal flakes from the tank. I had to end up sealing the inside of the gas tank with a tank sealer bought from Eastwood. No problems after that.

Re: Techniques for 2-cycle engine tools

Must be a Craftsman thing, my chainsaw does exactly the same thing.

t-manero, consider a self propelled front wheel drive lawn mower and mow up and down the hills. You should be able to live with that.

Re: Techniques for 2-cycle engine tools

I had a Stihl chain saw - it started quickly no matter what gas was in it. Now I have an Huskvarna and it starts fine. But I'm in a different climate.

Re: Techniques for 2-cycle engine tools
keith3267 wrote:

Must be a Craftsman thing, my chainsaw does exactly the same thing.

t-manero, consider a self propelled front wheel drive lawn mower and mow up and down the hills. You should be able to live with that.

Craftsman is now called Craftsman Brands . . . the hedge fund guy treats Sears as a "property" to be milked, and he is on record saying store upgrades is an unproductive use of capital.

Mowing lawn . . . I have a latino crew who mows 15,000 sf, cleans up and bags in about 25 minutes, and charges $30 per week maybe $35 this year. They won't do anything else for me like spring cleaning, mulching, weeding, even when I beg in Spanish.

Never touched a lawn mower in No. Virginia ("New Cambodia, USA"), nor in Silicon Valley.

Also, never seen a white guy working on lawn & landscape except the homeowner here in No. VA.


Re: Techniques for 2-cycle engine tools

Storing 4-strokes is easy enough, but 2-strokes do not store well. The big difference is that a 2-stroke needs crankshaft seals that are air-tight so that the fuel mix will be drawn in without air leaks thinning the mix or not drawn in properly due to poor vacuum because of leaky seals. 4-stroke or 2, the best way to store any engine is to use it at least every couple months under load and to keep the fuel fresh. Fogging oil in the cylinder(s) will help the piston rings and cylinder walls stay in good condition but if you run it often enough it is unnecessary. MMO or even plain old ATF in small amounts will help old seals stay soft but when that matters it's better to replace the seals before a leaky one leans the mix and fries the piston or cylinder. I am a fan of Stabil myself. Does it really work? I think so but since I run my engines regularly I really can't say. It's like those deer whistles on a car- nobody can prove that they don't work at least a little, and compared to the possible problem the cost is insignificant in comparison. One more thing- 2-strokes like clean spark plugs and in their environment they can foul rather quickly. As the magneto that fires them ages it becomes weaker so the older the engine, the more it needs a clean spark plug to start and run well.


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