Chainsaw Repair

Husqvarna - Stihl - Poulan - Jonsered - Dolmar chainsaws and more => Husqvarna => Topic started by: Spruce_Goose on February 04, 2015, 12:57:30 pm

Title: 357xp trouble shoot- machine gun throttle
Post by: Spruce_Goose on February 04, 2015, 12:57:30 pm
I've recently been getting odd behavior from my 357xp in the form of a rapid up/down of the throttle when fully open. It basically sounds like someone is hitting the throttle then letting go very quickly, like 2 times a second. Machine gun -ish. This all happening while holding the throttle wide open out of a cut and in the cut sometimes too. However oddly enough when the saw is fully loaded it oftentimes evens out.

The carb boot looks kinda loose, but i assume its normal to see some play there anyways? Without really having a clue, my current suspicions are: the impulse line, the carb, the fuel line, the carb boot, or the spark plug. No real reason I suspect those other than it acts like it is loosing fuel very rapidly and repeatedly. Not sure how spark plug issues manifest themselves so...

thanks for any advice,

spruce_goose
Title: Re: 357xp trouble shoot- machine gun throttle
Post by: Spruce_Goose on February 04, 2015, 01:00:52 pm
upon reading my post I suspect some may sight the coil limiter. While it is possible (I don't actually even know if the saw has one) it seems unlikely because this is happening even when in a moderate cut and at seemingly lower rpm. It doesn't sound to be reving all that high before the machine-gunning starts happening. If it is the coil, I would suspect that it is kicking in when it shouldn't. This more or less starting happening out of the blue (as I suppose most problems do). I did pull kind of hard on the saw though when it got stuck once, and it may have gotten worse after that...
Title: Re: 357xp trouble shoot- machine gun throttle
Post by: Cut4fun on February 04, 2015, 01:10:39 pm
Didnt read it all yet.

 But if this saw has the auto decompression valve remove it all and plug off.   Install manual decomp valve if needed.

Also the 199 carbs are known to go wonky on ya.
Title: Re: 357xp trouble shoot- machine gun throttle
Post by: 660magnum on February 04, 2015, 05:18:28 pm
The 357Xp/359 doesn't have a coil limiter, They have the black coil.

The boot is rather fickle where the carb fastens on. The screw threads in the boot are plastic and will strip easily.

Title: Re: 357xp trouble shoot- machine gun throttle
Post by: Spruce_Goose on February 04, 2015, 07:22:00 pm
Thanks for the reply's.

It is a manual decompression. Its an '06 357.

It has worked great until recently. I am leaning towards fuel issue. It started happening in the cut pretty consistently by the end of the day. I thought that a full tank of gas helped (leading me to think a leak in the fuel line), but I may have been imagining things.

Could a fuel issue cause this? Could a spark plug issue cause this? kinda stumped.
The carb boot area looks like it could use a good cleaning so I might start there. Maybe replace it. Then maybe fuel line and/or spark plug.
Title: Re: 357xp trouble shoot- machine gun throttle
Post by: 660magnum on February 04, 2015, 07:29:10 pm
I would start looking at the boot. It must be tight on the cylinder and the carb attaching screws not stripped out.

There is a small amount of fuel storage in the carburetor and a leak in the fuel line typically causes a lean running condition or the saw just stops.

The only area of the carb itself to cause this would be in the metering valve (regulator diaphragm) area?
Title: Re: 357xp trouble shoot- machine gun throttle
Post by: GCC on February 06, 2015, 03:29:51 am
 Have you checked the fuel filter? Or maybe some water in the carb ?
Title: Re: 357xp trouble shoot- machine gun throttle
Post by: Cut4fun . on February 06, 2015, 12:30:00 pm
I forgot about this till Jim mentioned it. If you have the plastic clamp.

Service Bulletin for 357XP, 359, 353, 346XP
This service bulletin is not new. I thought that there might be some out there who were not aware of it so here it is. If your saw has a black plastic clamp around the intake right next to the cylinder it is applicable to it. If the clamp is of steel construction then you should be ok.

B0600023
SERVICE

*537 43 88-01*
*compl 537 25 13-02
English 1 (1)

SB, 357 XP, 359, 353, 346 XP,
Partition wall and clamp for intake system,
2006-03

The existing intake system on 357XP, 359,353 and 346XP currently consists of an integrated plastic clamp in the partition wall. As the clamp is made of plastic, there is a risk of deformation. This results in impaired clamping force against the cylinder, which in turn can result in leakage in the intake system. To prevent this from occurring, we have now introduced a metal clamp and a new partition wall.

The new partition wall is made up of polyamide with 30 % fibre glass.
The new clamp is a hardened steel clamp. The new material and the design of the clamp reduce the risk of deformation and the subsequent risk of leakage.

Full replaceability prevails.
Introduced from serial number:
357XP 061100201
359 061100001
353 061100001
346XP 061100001

New part no. Description Excl. part. no. Remark
537 25 13-02 Partition wall, intake, complete New spare part
537 43 88-01 Clamp, intake New spare part

Spare part, partition wall, part number 537 25 13-01, has been discontinued and is replaced by part number 537 25 13-02.


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