i had a muffler bolt pull out last Sunday. Thread was full of block metal so i brought it to the local shop for a helicoil. He called me yesterday to say the piston and bore was in tough shape, which I know from peeking in the exhaust port. I went down to see it all apart and sure enough it hadn't gotten any better. It ran ok when I brought it down, and since I got the 562, I'm not in a rush to do anything with it. He wanted more money than I want to spend to replace the cylinder and piston. I've looked quickly on line and see kits from $229 on eBay for oem, to $90 at Baileys for NWP to others in much lower price range. Can I gets some experienced opinions on which way to go with this one?
Can you post pics of the cylinder and piston? Maybe you can just get a piston. If you have to get a new p/c go with the 346 44.3mm kit. I checked my local dealer about 6 months ago and he quoted me $105. It should be a direct replacement because I think they share the same crankcase. But hopefully you will only need a piston and clean up cylinder.
Me too! You can put that 346 top end on for an increase in performance. Direct swap and right around $100 Post some pics of the original cylinder. You may be able to salvage it with a little help from the knowledge here.
Should have taken a few pics when I was at the shop. I'll get it back put together, so no pics. The scores were pretty important. You could see them and feel them pretty easy with your fingers. I don't think I'd be able to sand the out. Even if I did, it would just be to open a clearance uniformly, matching the bottom of the scores. If going to open it up again far enough to change the piston, I'm going to do the cylinder too. Let me ask about the 346 vs a straight 353 replacement. The 353 is a 45mm kit and I wouldn't be swapping the muffler or crank. What makes the 346 kit a performance upgrade? Is the exhaust to the muffler a different geometry?
As far as I know the muffler and crank are the same on both saws. They share the same stroke, the differences are in the bore and port design. I think the 346 is a closed quad port compared to a 353 closed dual port. I have very limited trigger time with a 353 but from what I have heard the 346 topend will produce more power and more rpm's. It might not be night and day but noticeable. For around the same money getting the 353 topend doesn't make sense. Hopefully The Wood Wolverine and hdtoolmkr765 can confirm this!
That is correct, the 346 is closed port, 353 is open. If it just needs a piston, I wouldn't swap to a 346, a 353 with just a muffler mod and base gasket delete is still a pretty stout 50cc saw. If I had to do piston and cylinder both, it's a no brainer to go with the 346. The 353 has a little wider power band, but the 346 will spool faster, and have more RPM. OP, I was reading your post about sanding the cylinder and you stated something about clearance variation from sanding. Let me try to help you understand what you are actually seeing and feeling in your cylinder. Those grooves that you feel in the cylinder are more times than not, positive material. As the piston begins to overheat, the softer metal of the piston begins to stick to the plating on the cylinder. The plating on quality saws (like Husky, Dolmar, Stihl, Echo, Efco, etc) is very hard, the plating on those cylinders can withstand some serious sanding before damage can be done. Now, all that being said, there is a chance that the cylinder scored so haevily that it damaged the plating. In my experience it's rare, like around 4-5 in 1500 or so for myself, but it does happen. Seems that some guys have different experiences than me though, I also see a lot of talk about crank seals leaking, in the 1500-2000 saws that I've rebuilt and kept, sold etc, I've seen 2 with leaking crank seals, and both of them had bad crank bearings.
353 and 346 share the same bottom end, they just have different p/c's. 346 (new edition) is 44.3mm bore. If you get the piston/cylinder kit, it will simply bolt right up and run better than your 353 ever did. 353 cylinder is shard with the 350 (45mm 52cc new edition one) except it(353) has a flat top piston as opposed to the 350's dished one. Better cylinder / port design. It's a no brainer if you plan to get an OEM kit. 346 is true quad port, 353/350 is kind of quad, the transfer covers are removable and expose the ports. Here's a pic of the 346 to show the port buldges, you can see they are separate and well curved to direct charge flow. The one on your saw isn't as good. Your 353 cyl has these covers that do not direct flow as well.
353 isn't open port, EDIT: please correct me if I'm wrong. Here's looking up into the cylinder. And with the transfer port covers removed.
Correct, I have building so many Husky saws lately, they are all running together in my mind. Seems to be getting worse with age too. Thanks for clarifying.
