Blew up my husky 346xp

[barbender]

I'm bummed out cause I blew up my 1 1/2 year old 346xp this morning.   I really don't know what caused it.  I run 92 octane non-ethanol gas with jonsered oil at 35:1.  I was brushing a groove in the log home I am building, so the saw was running high rpm/low load. Not wide open, like 3/4 throttle.  Nothing was clogged in the cooling fins or anything, but it melted the piston at the exhaust port.  I've kind of suspected this thing of having a crank seal leaking or something, because when it gets cold (0 degrees F) it just ran like garbage, and you couldn't adjust the carburator enough to make it clear up.  Bring it to the dealer, they adjust the carb, charge me $20, and the saw runs no different.  I suggested an air leak to him, and he acts like I'm stupid or something.  So I just ran the thing (It ran fine once it warmed up a little)  and now my saw is toast.  Oh yeah, this saw was a bear to start when the engine was warm too.  Anybody have any ideas?  Anyone else had problems with this model.  Any feedback appreciated.

[StihlDoc]

It's possible that your saw has an air leak and is a simple diagnosis that a good two-cycle technician should perform as standard procedure when confronted with the symptoms you have described. Also, using a chain saw for scribing and hollowing out logs for log home building is one of the most demanding applications you can put a chain saw into. The machines are designed to run at wide open throttle under load. Some saws, depending on how the carburetors are calibrated, can have a lean fuel to air ratio at certain throttle positions between idle and full throttle. In a normal application it is not a problem because you usually are accelerating up to full throttle when cutting. The saws are "tuned" to run with the throttle shutter in a wide open position with the engine "under load". If you constantly hold the throttle at only a partial opening and the carburetor is not calibrated for running at that throttle position, you may have a lean fuel delivery that can lead to overheating and a piston seizure (melting).

[IndyIan]

Yikes!  melted pistons aren't much fun!
I think you should be in good shape with your warranty though.  You took it to the dealer, he "checked" it out and then it melted down.  New piston and cylinder time.
I might suggest getting it fixed at another dealer though...
Ian

[jokers]

........ Also, using a chain saw for scribing and hollowing out logs for log home building is one of the most demanding applications you can put a chain saw into. The machines are designed to run at wide open throttle under load. Some saws, depending on how the carburetors are calibrated, can have a lean fuel to air ratio at certain throttle positions between idle and full throttle. In a normal application it is not a problem because you usually are accelerating up to full throttle when cutting. The saws are "tuned" to run with the throttle shutter in a wide open position with the engine "under load". If you constantly hold the throttle at only a partial opening and the carburetor is not calibrated for running at that throttle position, you may have a lean fuel delivery that can lead to overheating and a piston seizure (melting).

I`d say that Stihldoc nailed it on this one. There is only a low speed fuel circuit and a hi speed fuel circuit in the carb of the 346, no midrange. What can happen is that running at partial throttle does not create enough engine vacuum to fully open the hi speed bleedback valve so the hi speed circuit is in essence un-calibrated for the engine load at that rpm.

Scribe and cope and chainsaw carving are both notoriously hard on chainsaws. I would richen the carb adjustments and run a premium oil at 32:1.

Russ

[tony_marks]

my sympathies. the fellas have given good advice. its a bummer to buy whats suppose to be a top end saw and have something like this happen..
 id go for an replacement if shes still under warranty tho. then go to another dealer as it may be this guy didnt  get you started rite. jmo

[barbender]

Thanks on the advice about the mid range lean spot fellas.  That makes sense, and in fact, if I hold the throttle in one spot when I'm brushing a lateral groove, the saw would sound lean.  So I tried to always work the throttle and keep the r's going up and down.  But besides that, this saw always had a bog to it( that sounde like a lean bog to me) that I couldn't get rid of no matter how much I turned the screws. That why I assumed there was an air leak or lean jetting or something.  I've had a few other saws ( 266 husky, 2165 jred, 2171 jred) and all of them have run like tops.  now, if you went from 70 degree weather  to 10 degree, any of those saws would need the carb adjusted, and then they ran great again. The 346xp, however, went from having an annoying intermittent bog at 70 to being nearly unusable at 10 degrees.  Sorry to ramble on, just trying to highlight the fact that something was up with this thing from the beginning.  Anxious to see what the dealer comes up with when he tears it down, he said he didn't expect husky would cover it. I guess I just have to wait and see. 

[Woodhog]

My 357 XP went lean with an air leak due to a faulty plastic clamp in the carburetor area.
My dealer said they used to all be metal and some were changed to plastic, if this is the case
in your saw and it had that defective plastic clamp Husky might go good for the saw...

My started to overrev and I stopped using it, they couldnt get it to slow down and tore it apart thats when they saw the broken clamp....they fixed mine for free

[barbender]

  Got some good news today- the dealer finished rebuilding my saw and husky is going to cover it.    The only bad thing is that he didn't find anything wrong as far as air leaks or anything,so i'll have to keep an eye on it. He said just the tear down and reassembly can fix some of those things (like if the carb boot wasn't clamped down right or a plastic clamp like woodhog mentioned). I'm just relieved husky made good on it with no bickering, it's things like that that can be the difference between a loyal customer or someone who would never buy that brand again. Woodhog- how do you like that 357xp?  I haven't heard much about those saws and was just wondering how they perform.  seems like everyone on here is either talking about 346's or 372's with nothing in between. (myself included)

[GlennG]

Husky recomends mixing fuel 50:1  . When you add more oil to the fuel mix, you lower the octane rating of the 2-stroke fuel. If the saw is run often there is a greater chance of "coking"( not cooking ) the spark arrester. This clogs the exhaust, reduces exhaust flow, increases engine temperature and leads to preignition/detonation and melts pistons. When mixing saw gas many people think more oil is better but its not. Using a quality 2-stroke oil from Stihl or Husky at 50:1 and your saw will last. Never use 2-stroke outboard motor oil or lawn mower oil, its not formulated for the high rpm`s that a saw operates at. This is the scoop I got from the mechanic at my saw shop. Good luck

Glenn

[Max sawdust]

Yes Husky recomends 50:1 not 35:1
I would start there. 
I have a 346XP and it runs and starts great.  It is a little rough running when the temp is around 10 degrees.  The 346XP has a winter flap so the carb can get preheated air.  Maybe give that a try when the temp is below zero.
Max

[Ed]

After you get the saw fixed, I would buy a slower rpm saw for what you are doing. That little 346 runs at 14700 rpm, it depends on chain speed to cut, not torque. If you keep using it like you are, I think you are going to have more problems down the road. 

Ed