372xpg with to little power ,,,,, ???

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SWE#Kipp

SWE#Kipp

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need help with my 372xpg it don't seems to got the power it should
And i can with not to much effort put it out of its powerband with 20" bar , i have changed the piston and ring ,, don't know what to do next !?!?!?
does someone have an idea of why it acts so "weak" ??

Thanks / Kristoffer
 
Simonizer

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SWE#Kipp said:
need help with my 372xpg it don't seems to got the power it should
And i can with not to much effort put it out of its powerband with 20" bar , i have changed the piston and ring ,, don't know what to do next !?!?!?
does someone have an idea of why it acts so "weak" ??

Thanks / Kristoffer
Why did you change the piston and ring? This tells me the cylinder must have also been damaged. Is the exhaust screen plugged? What does the spark plug look like? This will tell you something. Is it black and sooty, white and flaky, aluminum covered? work with me here buddy.
 
Mange

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I have talked tio kipp about this on the phone, and as I see it something is wrong.
I think this saw ir run too hot a few times, atleast one, the piston was damaged I am sure Kipp will tell you all details.
It runs fairly good, has comression, but does not have enugh power....

That will give you something to think about till Kipp gets off work.
 
SWE#Kipp

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i have polished the outlet and the intake, cause it was some carbon build up in the outlet but it's clean now ,,
i haven't done anything to the carb .
i have changed the impulse line as well just to be safe
 
pallis

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Replace the cylinder.
Rebuild the carb.
Follow some examples you can find here, and open up the muffler.
Use synthetic 2 cycle oil.

That's my .02. If you try all that, and it still doesn't run better, don't pay attention to me anymore. Listen to some of these guys who know what they are talking about.
 
spacemule

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Mange said:
I think this saw ir run too hot a few times, atleast one, the piston was damaged I am sure Kipp will tell you all details.
It runs fairly good, has comression, but does not have enugh power....
.
This sounds like a lean condition. Have you done a vacuum test to check your crank seals?
 
lesorubcheek

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Any way you can check the compression with a gauge? Maybe compare it to another good working saw as far as compression feel when cranking?

Dan
 
Mange

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If i understand him correct it is not over reving or starving for fuel.

Space, I think it was run hot before kipp got it.
It could still be bad crank seals, and the carb is set to overcompensate the additional air.

Rebuild the carb is never wrong I guess.
 
SWE#Kipp

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Guys i know there are bunch of chainsaw "gurus" can someone help me out here ,,, just tell me what kind of info you need of me :)
 

ehp

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Swe. it is not to hard, first is the motor up on compression and is the piston in good shape, I mean does it look like a new piston with no scratches or melted area trying to cover the ring. Measure your ring to see if it is wornout , it should be the same size all the way around.
If you find nothing so far then pressure test the crankcase to see if your seals are leaking.
If that is fine then what rpm is the saw taching out of the wood, around here with a 20 inch bar on a stock 372 we are using 13000 to 13500 rpm's out of the wood .
Start with that and you should fine 99% of your trouble. Another thing I have found on some saws where the owner runs low test gas is that sometimes the jug gets a glaze on the surface and the ring doesnot seat well after that.
 
SWE#Kipp

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I run my saws on aspen and the piston and ring is new ,,,, but still the saw feels gutless ,,, it feels like my 346 got more "balls" than the 372 :(
 
Marco

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you changed the impulse line. How is the fuel line? I have a 372 here for a sharpening, looked it over and it has that chunk of fuel line between the the tank and the bottom of the air box that gets alot of grief on the smaller Huskys especialy if the antivibe mounts are getting sloppy. Could have a crack in it through the air box grommet and it would be hard to detect.
 
jokers

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SWE#Kipp,

You stated that you have compression after changing the ring, but how much compression? Did you break the glaze on the cylinder when you put the new ring and piston in?

How about your decompressor, is it working cleanly, no leaks?

Russ

EDIT

After reading the whole thread I want to offer my apologies to those whom have already asked the questions that I apparently re-asked.

SWE#Kipp, you still have not answered the question on "how much compression?".
 

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