How to break in a Stihl Chainsaw

Gebo, the last Stihl tool I bought was a lineman’s augur drill and the dealer said that it would have an extended 5 year warranty if I used Stihl synthetic oil in it from day one. Not sure if that policy applies to chain saws. I’ve settled on Stihl synthetic for all my two stokes and it seems like good oil. I mix it 50:1
 
We run a fleet of Stihl saws at work and the break in procedure is run the however you see fit, never once had one wear out to the point that it was unusable, whem they get worn they get moved down to a crew that doesn't use the saws as much. We use Stihl Synthetic.

Usually when I break something like that in at home I vary throttle, load and thermal cycle it a bunch the first few hours.
 
I have yet to hold this bad boy at WOT, I just don't need to, it eats wood!

I was taught years ago that 1.) chainsaws are (were) designed to operate best at WOT under load (after break in) - i.e, bucking logs and 2.) Revving to WOT without load for extended time could cause damage to engine components (connecting rod, bearings, clutch, etc.). Limbing smaller branches would involve less than full throttle as needed.

This thread covers the topic pretty well: https://forestryforum.com/board/index.php?topic=91396.0 ....I tend to run my workplace weed trimmers and blowers at WOT most (not all) of the time also.
 
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It's good to gently warm up a 2 stroke. The piston expands faster than the cylinder. On new engines, the clearance is a bit tighter, so scoring can happen if not properly warmed up. Yes, most modern engines can tolerate the abuse of a short warm up. Even so, it's good to be careful.
 
Just did a quick check of blip-throttle warm up times. My 21cc Echo blower takes 40 seconds before the cylinder fins are too hot to touch (about 140 degrees) and the same for my 26cc Echo trimmer. Both were blowing warm air out of the fins after 40 seconds.

My Stihl BG86 blower took a full 60 seconds before any warm air was blown out of the fins (can't touch them due to shrouding)
 
I've had a Stihl MS 361 a few years now its always ran great. first time I used it I started it let it warm up and then I started cutting firewood. Never has had an issue. But it must use oil it smokes a little not much but a little 🎣
 
Not being dismissive or rude - but why on earth, would you run a 2-stroke engine on 100:1 mix? Even the EPA mandated manufacturers' ratios are nothing of the sort. What does one 'gain' from 100:1 compared to even 50:1?

It is just something that I have done from the beginning and following what is stated on the AMSOIL 2 cycle bottle, this is before it was labeled as Saber. It has worked for me for a long time. I have an old (21 years old) Kawasaki string trimmer. It has nothing but AMSOIL 2 cycle in it at 100:1. It doesn't get used as much now that my in-laws have passed and I don't have to trim their fence line on 5 acres of land.

Also an Echo mulcher/vac. Same thing. Runs great but it is only 9yrs old.

I understand that most can't comprehend running such a lean mixture, but all I can say is that it works for me and the throttle response is crisp and plenty of power with no smoke.
 
Personally what I do is mix at the recommended ratio with ethanol free fuel. Fire up the saw and let it warm up at idle for maybe a minute, then cut some small limbs, about 12-15 times, with it. After doing that, jump into some of the bigger stuff. Best thing to remember is always give the saw about a minute to warm up before hitting it WOT. Fire up the saw, let it idle with the brake on, grab your protective gear, then have at it.

L8R,
Matt
 
For break in:
-Always use only ethanol free fuel, however you have to obtain it.
-Mix at least 40:1 not 50:1. Richer will never hurt.
-A very minor enrichment to the carburetor screws H/L
-Must let engine warm up, and never go to wide open throttle until the engine is up to temp. There are photos online to show you all about cold seizing. This happens on chainsaws more then other types of 2 cycle engines due to their very high RPM potential.
 
And the rich vs lean argument:

Rich = will carbon foul plugs, plug up muffler screens, and varnish ring lands on the piston with is able to be dissolved with a piston soak.

Lean = Will wear out and score piston / cylinder, overheat the wrist pin and upper bearing, melt the piston to the piston ring, and in some cases where the engine is operated at high RPM for a long time with just enough amount of oil to prevent siezure, the carbon will literally bake the ring to the piston.

When mixing fuel ratios leaner than 50:1, you must be very carful with your measurements, lots can go wrong. The film left in the bottle at this point can make a huge difference.
 
I have all Stihl stuff but I'm just a homeowner, but have 13 acres to maintain.
I have a 271 that I bought new last year. I ran it through a couple of complete heat cycles then she went to work.
I buy the min amount of Stihl oil it takes to double the warranty, but I never use it. If you look at the spec, there are much better 2 cycle oils on the market. I use VP 2 cycle oil, better specs for less money. I get E0 fuel from a local lawn equipment repair shop or the marina.
 
Talked to Stihl Rep. He said no extended wide open throttle without wood for resistance and under no circumstances should I ever mix oil at a higher concentration than what owner's manual says. He said it is the gasoline that cools the engine. Extra concentration of oil could cause the engine to overheat.

And if you want to really take care of your 2 Strokes, use Motomix. FWIW....
 
After many saws over many years of fairly heavy use, I've learned a few things about breaking in a new saw. You can follow some ocd procedure or you can just use some common sense and you'll end up in the same place 10 years later. So, I use a new saw kind of gently for a few hours of use. No cold start high revving, and no extended cutting sessions with the saw hot as can be. That's it. No special tuning, no rich carb, no special mix, just common sense. Just don't go out and rev the crap out of it right out of the box and you'll likely be just fine
 
My Son-in-Law just bought me a Stihl 250 chainsaw. Mighty nice, huh? I know to use the Stihl engine oil for warranty purposes. Would you use their synthetic oil for break in? Do you follow any certain procedures at first? I'm only using non-ethanol gasoline..
Plan on 6 tanks of gas run through the saw before it is broke in. After each tank of fuel you will notice that the saw turns faster. 50:1 mix, 89 or more octane fuel. Don't let it idle very long. Cut wood at full throttle so you will break in the engine. I have been using Stihl for years. NGK plugs, high octane fuel, good 2 stroke oil keeps them running for years. Flip the bar over each time you swap chains, clear the bar groove of sawdust each time. Keep the air filter clean and that is all you need to do.
 
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