Yotaismygame
Juiced Saws #GetJuiced
I took in a first year 1999 346xp on trade. Owner said it was a good running saw. (need to talk with him to confirm). When I got it compression felt good, started right up and ran. I only ran it for maybe ten seconds than tore it apart for porting. What I found was a scored piston. So in went a new piston and vac/pressure tested it...more than once. No leaks. From there I replaced the fuel line/filter. Took the carb apart and put it in the ultrasonic. Carb looked clean before it took a bath.
Here's the symptoms: If the low is adjusted a little lean it will stay running but the idle seems too high. Can clearly hear its idling lean. If I richen it up at all it will act like fuel is pooling bringing the idle too low then it dies. Takes three pulls to get her going again and sometimes the high idle is needed. Frist trigger pull it acts slightly flooded. The high side seems completely fine and is consistent. It doesn't seem like a air leak based on testing and how consistent it runs. Just seems like there is no happy medium between a lean idle and too rich. I played with the low jet for at least 30 minutes and never came to a conclusion. I have read about the tank vents on these being an issue especially after porting. I cracked the fuel cap on it while running and it made no difference. All the threads I read about the tank vent and modding it were not about this specific model/year.
I'm open to suggestions on what's going on here. Seems odd the piston was scored but it also looked like someone had cleaned it up and the cylinder maybe tossed a new ring on and ran it. Air leak? I tore it apart and found no bubbles while under pressure. I'm leaning towards a carb issue. ?????
Edit: I did find a leak on the intake boot when I first tested it after porting. Replaced the clamp with a better one and it solved that issue. Maybe that was the cause of the original scoring.
Here's the symptoms: If the low is adjusted a little lean it will stay running but the idle seems too high. Can clearly hear its idling lean. If I richen it up at all it will act like fuel is pooling bringing the idle too low then it dies. Takes three pulls to get her going again and sometimes the high idle is needed. Frist trigger pull it acts slightly flooded. The high side seems completely fine and is consistent. It doesn't seem like a air leak based on testing and how consistent it runs. Just seems like there is no happy medium between a lean idle and too rich. I played with the low jet for at least 30 minutes and never came to a conclusion. I have read about the tank vents on these being an issue especially after porting. I cracked the fuel cap on it while running and it made no difference. All the threads I read about the tank vent and modding it were not about this specific model/year.
I'm open to suggestions on what's going on here. Seems odd the piston was scored but it also looked like someone had cleaned it up and the cylinder maybe tossed a new ring on and ran it. Air leak? I tore it apart and found no bubbles while under pressure. I'm leaning towards a carb issue. ?????
Edit: I did find a leak on the intake boot when I first tested it after porting. Replaced the clamp with a better one and it solved that issue. Maybe that was the cause of the original scoring.
