Muffler, any down side?

[timberwolf]

I'l open up my new 026 tonight

Very good point on the breakin, I think I will fix the muffler on it tonight. Or maybe even today at work if things are slow.

Thanks
Timberwolf

 

[Greg]

Is it a good idea to let a new saw idle through (just sitting) a tank of gas to help it break in? Any other ok methods to break in a saw faster?
I just bought a Stihl BP340 blower, in the manual it says not to run at full throttle until it is broken in, the saw shop said ignore that, it is ready to rock. From reading this forum I now want to screw with all of my saw mufflers. Is it ok to also do this on my blower? Or does it have other internal parts that might be matched to the stock engine specs, or is an open muffler a better muffler for ALL 2strokes?

Greg

 

[bwalker]

Is it a good idea to let a new saw idle through (just sitting) a tank of gas to help it break

Not IMO. Two cycles dont require much break in as they use ball/roller element bearing on the crank shaft/conrod. About the only thing that need to "break in" on a two cycle is the ring to cylinder wall interface and of course a few heat cycles to relieve pent up stress in the metal from mfg. What I do is sart the saw up and let it warm up till the cylinder is hot, then shut it down and let it cool completly. I repeat this a few times to relieve any stress in the metal. I than fire the saw up and alternate between periods of heavy and light load makeing sure not to load the motor to hard for too long. Do this for a two tanks of fuel and then just run it like normal. Prolonged idle does not seat rings properly because ther is no load. On the contary it may cause glazing which will hamper ring seating and development of full power.

 

[don]

Same thing with 4 strokes

Don't warm up a new engine in idle .. can cause glazing.

This is a hot topic.

Heard two methods to break in an engine.

Run at various RPMS for 100 miles or

Run it where you would race it.

Some guys even use a special "break in oil" usually much higher weight they would race.

 

[sedanman]

Back in the olden days of drag racing folks like Don Garlits used to "break in" a new fuel motor (they lasted more than 1 pass in those days) by letting the rear tires hang off the trailer and they'd take the plugs out of the motor to seat the rings.

 

[eyolf]

BWalker has a much more involved and detailed break-in sequence than most people...including me!

Most of us take it easy through the first tank of gas..."no extra long, hard, full bore, banzai action for the first tank, then let me at it"

I've never had a problem...If a saw wears out a little too fast, then that's an excuse to get another one!