Holidays Greeting and Good Wishes to All!
Starting with a (maybe-not-so-short) story, I am seeking the advice of this vastly-knowledgeable hive of smart wood cutters. If you wish, just skip to "So, here's my question:" below.
It all started about 3 weeks ago while cutting firewood. My beloved Husqvarna 350 decided to part with its muffler and spat it away... Of course, I realized that this all my fault for not taking care of my slowly-but-surely failing muffler bolts: a few weeks earlier one bolt slipped away unnoticed, never to be seen again, and I just carelessly continued to operate the saw with the occasional tightening of the remaining bolt. Only after the 350 angrily spat that muffler and I was doing some online reading, did I realize that I was on the very popular road shared by many 350 owners... Upon further inspection, I realized that the thread of that remaining bolt was stripped in the cylinder head, thus allowing the engine to shoot away the muffler, declaring its victory with a roar that could wake up the dead...
Solutions such as helicoil or other inserts were usually not given favorite opinions or results from what I read. I was faced with two options: tap the head and use larger diameter bolts, or replace the cylinder and use new, original bolts. As I was contemplating the issue, I peeked through the exhaust port and discovered that the piston seems to be scored. Probably a punishment for my negligence in keeping an eye on the muffler and the bolts... Compression test came up with about 70-75. Time for a closer look! I took the cylinder off, and while the head itself was nice and smooth without any scoring signs - the piston was definitely a goner... Well, I guess the decision of what to do has already been made for me: so I ordered a piston/cylinder kit. Rush delivery, of course.
Two days later, my arms cradle the new piston/cylinder baby. It takes *much* less time to write about it than to install it - but I finally got it all assembled and bolted together. (I am going to skip the l-o-n-g time I spend troubleshooting mis-routed fuel lines, leaking connections, and fuel-tank vent that decided to jump ship...) At that moment, I also realizing that I forgot to order two new muffler bolts... Argh! Of course no Husky dealer in the area has these in stock, but I find in the hardware store a matching threaded rod! Threaded rods are Locktited in, heat shields and muffler follow suit, and two nuts secure the set in place. Voila - the moment of truth has arrived: time to pull some starting cord!
So I pulled, and nothing happened. And I pulled again, and nothing happened again. And I pulled some more. I dripped some fuel to the carb, pulled, and the engine barely coughed. It's Michigan, and it's cold, but I was steaming hot. WHAT IS GOING ON??? Ignition spark? - Check. Plug not soaking wet? Check. Primer bulb pumps the way it should, with the line to the carb spittting fuel when I push the primer? Check. Engine runs? NOT check... Somehow fuel delivery from the carb to the engine seems to fail. Time to get the carb off (again...).
Ta-Dah! right below the main opening of the intake, there's another smaller opening in the cylinder that is supposed to deliver pressure from the crankcase (as the piston goes down) to the carb and pump fuel. In the original head that I took off, this opening goes through straight into the cylinder cavity; in the new cylinder I put on, this opening is NOT going through, but instead it "bends down" where it's supposed to meet a matching opening in the crankcase body through the gasket, and from that point it (probably) turns again into the crankcase cavity. But since that is not the design of the crankcase on my 350 - that fuel-pumping opening was simply blocked! My bright revelation for that moment: if you can't pump fuel to the engine - it will not run... Bear in mind that at this point I'm about a week+ into this project. The prospect of requesting a replacement, shipping and waiting and exchanging the cylinder is not a happy one. And winter is not one that is known to be patiently waiting...
OK, remember my original two options? Time for a combo-meal: tap the old cylinder for larger muffler bolts, and install it on the new piston. Forget that darn wrongly-ported new cylinder head. So, remember the "Karate Kid" movie - "wax on - wax off, wax on - wax off..."? Here we go again: everything gets disassembled and reassembled all over again (have I already said that it takes *much* less time to write about it than to install it?...) The last bolts to go on are the new, larger muffler bolts. With Loctite. Not too tight. I swear. And...? New bolt strips new thread ! <Explicits>!!!!!!
Update: the guy who runs the workshop where I work, who was very helpful in helping me troubleshoot the problems with the chainsaw, just sent me an email "Go cut wood..." Apparently, seeing how upset I was with the saw, he just took it apart again, put a helicoil in the head, and it's up and running again.
But: I don't know how long it will last, and I cannot trust it as my main and only saw anymore. While I'm not a professional, I still cut about 5+/- full cord/year as a homeowner. This 350 has just been demoted to a backup saw.
So, here's my question:
What would you recommend as an equivalent replacement for the 350?
At some point in the near future I plan on supersizing with something like the Husqvarna 372XP for larger-diameter cuts. But it's too large/heavy for most average use; I need something between my Stihl MS190 and the future 372XP that will be reliable and easier to handle.
Thank you,
Zevi.
Starting with a (maybe-not-so-short) story, I am seeking the advice of this vastly-knowledgeable hive of smart wood cutters. If you wish, just skip to "So, here's my question:" below.
It all started about 3 weeks ago while cutting firewood. My beloved Husqvarna 350 decided to part with its muffler and spat it away... Of course, I realized that this all my fault for not taking care of my slowly-but-surely failing muffler bolts: a few weeks earlier one bolt slipped away unnoticed, never to be seen again, and I just carelessly continued to operate the saw with the occasional tightening of the remaining bolt. Only after the 350 angrily spat that muffler and I was doing some online reading, did I realize that I was on the very popular road shared by many 350 owners... Upon further inspection, I realized that the thread of that remaining bolt was stripped in the cylinder head, thus allowing the engine to shoot away the muffler, declaring its victory with a roar that could wake up the dead...
Solutions such as helicoil or other inserts were usually not given favorite opinions or results from what I read. I was faced with two options: tap the head and use larger diameter bolts, or replace the cylinder and use new, original bolts. As I was contemplating the issue, I peeked through the exhaust port and discovered that the piston seems to be scored. Probably a punishment for my negligence in keeping an eye on the muffler and the bolts... Compression test came up with about 70-75. Time for a closer look! I took the cylinder off, and while the head itself was nice and smooth without any scoring signs - the piston was definitely a goner... Well, I guess the decision of what to do has already been made for me: so I ordered a piston/cylinder kit. Rush delivery, of course.
Two days later, my arms cradle the new piston/cylinder baby. It takes *much* less time to write about it than to install it - but I finally got it all assembled and bolted together. (I am going to skip the l-o-n-g time I spend troubleshooting mis-routed fuel lines, leaking connections, and fuel-tank vent that decided to jump ship...) At that moment, I also realizing that I forgot to order two new muffler bolts... Argh! Of course no Husky dealer in the area has these in stock, but I find in the hardware store a matching threaded rod! Threaded rods are Locktited in, heat shields and muffler follow suit, and two nuts secure the set in place. Voila - the moment of truth has arrived: time to pull some starting cord!
So I pulled, and nothing happened. And I pulled again, and nothing happened again. And I pulled some more. I dripped some fuel to the carb, pulled, and the engine barely coughed. It's Michigan, and it's cold, but I was steaming hot. WHAT IS GOING ON??? Ignition spark? - Check. Plug not soaking wet? Check. Primer bulb pumps the way it should, with the line to the carb spittting fuel when I push the primer? Check. Engine runs? NOT check... Somehow fuel delivery from the carb to the engine seems to fail. Time to get the carb off (again...).
Ta-Dah! right below the main opening of the intake, there's another smaller opening in the cylinder that is supposed to deliver pressure from the crankcase (as the piston goes down) to the carb and pump fuel. In the original head that I took off, this opening goes through straight into the cylinder cavity; in the new cylinder I put on, this opening is NOT going through, but instead it "bends down" where it's supposed to meet a matching opening in the crankcase body through the gasket, and from that point it (probably) turns again into the crankcase cavity. But since that is not the design of the crankcase on my 350 - that fuel-pumping opening was simply blocked! My bright revelation for that moment: if you can't pump fuel to the engine - it will not run... Bear in mind that at this point I'm about a week+ into this project. The prospect of requesting a replacement, shipping and waiting and exchanging the cylinder is not a happy one. And winter is not one that is known to be patiently waiting...
OK, remember my original two options? Time for a combo-meal: tap the old cylinder for larger muffler bolts, and install it on the new piston. Forget that darn wrongly-ported new cylinder head. So, remember the "Karate Kid" movie - "wax on - wax off, wax on - wax off..."? Here we go again: everything gets disassembled and reassembled all over again (have I already said that it takes *much* less time to write about it than to install it?...) The last bolts to go on are the new, larger muffler bolts. With Loctite. Not too tight. I swear. And...? New bolt strips new thread ! <Explicits>!!!!!!
Update: the guy who runs the workshop where I work, who was very helpful in helping me troubleshoot the problems with the chainsaw, just sent me an email "Go cut wood..." Apparently, seeing how upset I was with the saw, he just took it apart again, put a helicoil in the head, and it's up and running again.
But: I don't know how long it will last, and I cannot trust it as my main and only saw anymore. While I'm not a professional, I still cut about 5+/- full cord/year as a homeowner. This 350 has just been demoted to a backup saw.
So, here's my question:
What would you recommend as an equivalent replacement for the 350?
At some point in the near future I plan on supersizing with something like the Husqvarna 372XP for larger-diameter cuts. But it's too large/heavy for most average use; I need something between my Stihl MS190 and the future 372XP that will be reliable and easier to handle.
Thank you,
Zevi.
R
For me it was a mecca to the holy land!!!
