550xp strong in cut; sometimes hard to start and hesitates off idle

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Sounds like it to me also.... cold saw.

Yeah, it's improved so it's almost normal I agree, but it used to die and was very erratic on start similar to what OP posted so I figured I would confirm similar issues, and just want to be updated in case there is a firmware revision or something like that - or maybe it's part of autotune/saw break in.

See TommySaw post here about cold starting issue:

http://www.arboristsite.com/chainsaw/208570-3.htm

Maybe he can provide more detail, again no big thing, it's an awesome saw, I love the thing.
 
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Half of my saws are that way. They have to warm up a bit before you can hit the trigger.

The difference for me is that this saw sometimes won't keep running on its own at high idle at a cold start. It fires on choke, then starts on the 2nd or 3rd pull with the choke off, but sometimes dies after 1 or 2 seconds -- without touching the throttle. It sometimes then takes 2 - 4 pulls again to get it to fire at high idle, then it dies again. Then maybe on the third or fourth re-start it will stumble along on high idle until finally it smooths out and I can touch the throttle to release the high idle. Colder temperatures seem to make it worse. Using the air purge more or less doesn't seem to make a difference.

Again, I can put up with it. It's just the hardest starting 2 stroke I own. I probably wouldn't have started the thread it if it weren't for also having the bogging off-idle symptom. When you grab a fist-full of throttle, hearing your saw stumble or drop RPMs, even for a split second, doesn't give you confidence. Neither of these is a major issue, but since I have both of them I thought I'd ask other folks what their experience has been.

I appreciate all the input. It's really helpful to hear.
 
The difference for me is that this saw sometimes won't keep running on its own at high idle at a cold start. It fires on choke, then starts on the 2nd or 3rd pull with the choke off, but sometimes dies after 1 or 2 seconds -- without touching the throttle. It sometimes then takes 2 - 4 pulls again to get it to fire at high idle, then it dies again. Then maybe on the third or fourth re-start it will stumble along on high idle until finally it smooths out and I can touch the throttle to release the high idle. Colder temperatures seem to make it worse. Using the air purge more or less doesn't seem to make a difference.

Again, I can put up with it. It's just the hardest starting 2 stroke I own. I probably wouldn't have started the thread it if it weren't for also having the bogging off-idle symptom. When you grab a fist-full of throttle, hearing your saw stumble or drop RPMs, even for a split second, doesn't give you confidence. Neither of these is a major issue, but since I have both of them I thought I'd ask other folks what their experience has been.

I appreciate all the input. It's really helpful to hear.

Well, that's just not right. I'd investigate that L screw Brad mentioned, or get it back to the dealer ASAP!
 
Hey Brad I sent you a pm the other day with questions on 550 and was wwondering if u get them am could maybe help me thanks
 
I called my dealer, and he said he could look at the saw in the next day or two if I brought it in. I dropped it off this morning and did my best to describe the symptoms. I'll post back with an update when I have one.
 
There's actually a L needle on the 550. It sounds like yours needs opened 1/4 turn. It's in a recess on the face of the carb, on the left side.

OK, guess I learned something today - but are you sure it is correct to call that one an L screw/needle. :msp_confused:
 
OK, guess I learned something today - but are you sure it is correct to call that one an L screw/needle. :msp_confused:
it is amazing what a guy can learn when he actually has owned/ran/used the saws he blows about all the time. hmmm.......guess you need to do more than read specs, and look at pictures.:biggrin:
 
OK, guess I learned something today - but are you sure it is correct to call that one an L screw/needle. :msp_confused:

it is amazing what a guy can learn when he actually has owned/ran/used the saws he blows about all the time. hmmm.......guess you need to do more than read specs, and look at pictures.:biggrin:

ST has already stated here on AS that he has NO experience with a 550 when ask that question he replied "Zero" experience so it had to be using it on the internet :msp_thumbup:


CATDIESEL you have been rep for that post :)
 
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it is amazing what a guy can learn when he actually has owned/ran/used the saws he blows about all the time. hmmm.......guess you need to do more than read specs, and look at pictures.:biggrin:

Well, it hardly is a secret that I don't own a 550xp (yet), and it is hard to understand what bothers you.:msp_rolleyes:


Just put me on ignore - so my posts don't bother you, since you obviously don't like them......:hmm3grin2orange::hmm3grin2orange:
 
I took the saw back to the dealer for him to investigate. He does have the diagnostic tool, but he didn't find any codes or errors for the saw.

He said he did a "master reset" and that it seemed to help the starting problem. The slight and occasional stumble off idle was unaffected. He said he tried a 562xp AT alongside my 550xp, and the 562 did the same thing off idle when hot. He had never noticed that before. He also said he had his "Autotune school" coming up in about a month and would let me know if he heard anything that would help. I like him, and I believe he genuinely wants happy customers.

I've now used the saw for a few weeks after the "master reset," and the saw behaves the same way it did before I took it in. If I follow the manual's instructions for starting on a cold morning, it's a truly frustrating experience because the saw won't stay running once it starts.

I can get it to run by repeating the entire starting process 3 times (primer bulb only gets worked before the whole series, not each time): choke on--choke off--dies; choke on--choke off--dies; choke on -- choke off -- finally keeps running.

So I have a workaround that requires a little extra fiddling and extra pulling (maybe 12 - 15 pulls total) when it's cold. Once I'm working with it and keep it hot, the Formula car handling and power in such a small package makes me smile despite its starting and slight stumbling behaviors.

I like the saw so much that I might consider replacing the carb as an experiment. Does anyone know what a new AT carb costs? If you replace the carb, do you also have to replace the ignition module as well, and if so, how much would that cost?
 
I took the saw back to the dealer for him to investigate. He does have the diagnostic tool, but he didn't find any codes or errors for the saw.

He said he did a "master reset" and that it seemed to help the starting problem. The slight and occasional stumble off idle was unaffected. He said he tried a 562xp AT alongside my 550xp, and the 562 did the same thing off idle when hot. He had never noticed that before. He also said he had his "Autotune school" coming up in about a month and would let me know if he heard anything that would help. I like him, and I believe he genuinely wants happy customers.

I've now used the saw for a few weeks after the "master reset," and the saw behaves the same way it did before I took it in. If I follow the manual's instructions for starting on a cold morning, it's a truly frustrating experience because the saw won't stay running once it starts.

I can get it to run by repeating the entire starting process 3 times (primer bulb only gets worked before the whole series, not each time): choke on--choke off--dies; choke on--choke off--dies; choke on -- choke off -- finally keeps running.

So I have a workaround that requires a little extra fiddling and extra pulling (maybe 12 - 15 pulls total) when it's cold. Once I'm working with it and keep it hot, the Formula car handling and power in such a small package makes me smile despite its starting and slight stumbling behaviors.

I like the saw so much that I might consider replacing the carb as an experiment. Does anyone know what a new AT carb costs? If you replace the carb, do you also have to replace the ignition module as well, and if so, how much would that cost?

Try using the purge bulb more. I use the bulb on mine (562xp) every time I start it. 3-4 pulls cold, one pull warm. Back to the dealer if this doesn't help...
 

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