XL-123 Problem

[Jarhead ☠]

So I've put a lot if time and some money into this saw, OEM carb kit with accelerator pump, new cylinder, piston, rings and coil and it still has an issue with reving. I'll post a video tonight but the saw starts fine and will rev a while but suddenly it will start to sputter. My initial thought was the carb with the new accelerator pump but it's a very simple clean and replace item.
Does anyone have an idea as to what it might be?

[fossil]

Aug 26, 2021 11:24:48 GMT -5 Jarhead ☠ said:

So I've put a lot if time and some money into this saw, OEM carb kit with accelerator pump, new cylinder, piston, rings and coil and it still has an issue with reving. I'll post a video tonight but the saw starts fine and will rev a while but suddenly it will start to sputter. My initial thought was the carb with the new accelerator pump but it's a very simple clean and replace item.
Does anyone have an idea as to what it might be?

Sounds like fuel delivery. Check the fuel line and filter.



A good way to eliminate the line and filter as a problem is to pull the line off the carb and attach a loose piece of line and run the saw on fuel mix from a can or bottle.



Make sure the container doesn't spill onto the muffler to prevent much dancing and swearing.

If the line and filter are OK, maybe you have another saw you could swap a carb from?

[charles]

  Could be a fuel tank vent problem .  I'm not familiar with XL-123 family of saws and don't know where the vent is , but you can (carefully) run

the saw with the fuel cap loose to check for a venting problem .

Charles

[edju1958]

The venting on the 123 is in the fuel; cap duck bill.

Rather than use a separate fuel container,just run the dummy line from the carb into the tank with a fuel filter of course.

The problem might not ber in the fuel system,but rather in the ignition system.It almost sounds like you have a condenser that's beginning to break down.If it's possible,put a chip in it & see if the problem persists.If it persists then you can rule out the ignition system,but if the saw runs flawlessly then you know it's ignition system & not fuel system related .

[lesorubcheek]

Aug 26, 2021 12:16:39 GMT -5 edju1958 said:

The venting on the 123 is in the fuel; cap duck bill.

Rather than use a separate fuel container,just run the dummy line from the carb into the tank with a fuel filter of course.

The problem might not ber in the fuel system,but rather in the ignition system.It almost sounds like you have a condenser that's beginning to break down.If it's possible,put a chip in it & see if the problem persists.If it persists then you can rule out the ignition system,but if the saw runs flawlessly then you know it's ignition system & not fuel system related .

Agree. I had similar symptoms on a David Bradley years ago. It'd start and idle fine, but give it some throttle and it'd just sputter. Was convinced it had to be a problem with the carb. After tearing the carb apart multiple times and no change in behavior, finally decided to check ignition components. After swapping the condenser, it started running perfectly. Still keep this failed condenser handy since it's a perfect example of how one can actually show proper capacitance on a meter, but fail a leak-down test.

Dan

[Jarhead ☠]

I'm going to try a different SDC carb and go from there with a condenser. Everything else has been done with all brand new parts.

[fossil]

Best wishes with it. Some saws are frustrating for sure.

[Jarhead ☠]

Not sure what it is about this saw that I really love because I spent more money than it's worth on it.

[fossil]

Peppy saw and great handling. You'll be pleased with the end result.

[Jarhead ☠]

It's been running all along, this is something that just started to happen. This saw along with my Super 1050 and the super XL are in my saw box.

[edju1958]

You've got a great "go to" trio there Al,although the closest I've got to a 1050 is an XP1000.I've got 2 123s & they're definitely worth putting money into.The 1st 123 I got I paid $15 for & it didn't need much to get it going - new set of points & condenser,new switch & wire.I didn't even have to pull the carb.The 2nd 123 I think I paid $40 for on Feebay.That one needed points & condenser as well,carb rebuild,new fuel line,bar plates,& new muffler,& it was ready to go.For a 57cc saw they really pack a punch.

[Jarhead ☠]

I'm starting to get the feeling that my XL-123 doesn't like me!🤔 Got everything straightened out I believe and go to pull her over and BAM! No more tension.

[edju1958]

I'd say the old spring had the weiner,Lol.