Well, my 346xp stopped running on me a while back. I had checked the compression and it was super low. I had dropped her off at my normal saw shop. They gave her back to me in a box, but left the muffler off so that I could see the scored piston & cylinder. I was debating on having it done, doing it myself, or using her as a parts donor. The shop didn't seem very interested in fixing it and was pushing for a new saw sale. Not that I won't buy from them again, but I wasn't ready to take the plunge on another new one. Though I've been thinking of a ms261 or 550xp, to make the jump to M-tronic or Auto Tune. But, I don't need the 5 saw plan right now... I just really love this little 346xp. I decided that with the cost of a 44.3mm kit and what the shop wanted to charge that I'd order the parts, some additional tools, and give it a go at doing the work myself. Lesson learned on this one, I took way too much of the saw apart for what I actually needed to do. So, I just finished putting her back together last night and she seems to run great! I had NO leftover parts, and was only missing one piece that I've since ordered. It was a rubber isolator or limiter for the AV system. I'm unable to remember if it was there when I tore her down and I lost it. Or, if it was already missing and I needed it anyway. I wanted to say thanks to the members here for all of the great content. I probably would not have tackled the job without all of the awesome threads! Now, do I dare delve into doing some port work on my own?
Wise choice as they are one of the best 50cc saws ever made! Any idea what caused the saw to score like that in the first place? And I’d leave the porting to the pro’s. The grinder needed (90degree tip) isn’t cheap. I did one that had removable transfer port caps and it went pretty good. I had one of those pro’s show me how to degree wheel and mark where to grind though.
The Wood Wolverine, I haven't found out what happened to cause the problem yet. I was hopeful that maybe the rubber intake boot (probably not the correct terminology) would have been split and caused a lean running condition or something. But, it all looked fine. I'm religious about appropriately treating & mixing all of the fuel that comes into my shop. So, I hope it was just a one off wear & tear thing. I did purchase that saw used a few years ago, so I don't know what kind of life it had prior to the loving care it gets here... LOL.
Nice job! I agree tare down may be more than was needed, but now you’ve seen how it goes. Looks like that model has the metal intake clamp. If it was still fastened, I wouldn’t suspect the boot as the leak, although possible. That saw has a pretty tight AV between tank and case so not a lot of relative motion to tweak it. I’d give it a good Carb Cleaner spray at idle around the seals just to be safe. Looking at the cylinder pic, it looks a lot dirtier on the pull start side cylinder bolt than the PTO side. I might suspect a cylinder bolt or flywheel side crank seal
Next time you start it, with the brake on, rotate the saw around in all directions. See if the idle changes. This can also be a quick way to spot a bad crank seal. I do like the method M2 described too. It’s a very easy way to see if air is leaking into the saw where it shouldn’t, it’s just hard to get it near those crank seal spots.
I got to run 2 tanks through her yesterday. The turn it in all directions did not change the idle any. She's running pretty great! I did shut her down when one of my av spring screws came up missing. I was unable to find it in the leaves / creek... But, all in all, I am pretty happy that I was able to do this repair and the outcome. I am still considering taking the leap to an M-tronic MS261 or an Auto Tune 550xp. Decisions, decisions...
