Finally, a 350 of my own! (Porting project)

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Isaac Carlson

Minister of Fire
Nov 19, 2012
1,131
NW Wisconsin
First a little story...

A few years ago, I repaired and ported a husky 350 for a friend. It had been put together with silicone by a previous owner, none of the bolts were tight, and it would not run. It had a 45mm cylinder with transfer caps, so I ported it to be a fast work saw. It still had a dished piston and the squish was pretty stock. It ran like crazy and I fell in love with it. He lets me use it at his house, but won’t sell it to me. I have been looking for another one for a few years.

Well, about a month ago I was replacing a few windshields for a grain store about an hour away and something told me to ask if they had an old 350 laying around. The guy behind the counter looked very confused/surprised and said he would be right back. He came back a minute later and said there was one in the back that had been rebuilt after being straight gassed......and it was for sale. I asked if I could see it. He fired it up and it was not tuned very well, but sounded pretty good. It had not made a cut since being rebuilt, and I expected something to be wrong with it from past experience with small engines that had been worked on. I asked the price and it was pretty close to what I expected ($140). I offered $100 for it and he wrote it up.

I gave it a good inspection after work and found clear silicone in the spark plug and chunks of silicone in the cylinder....sound familiar? It cut wood ok, but would not hold a steady tune. I could tune it after every cut and it would keep changing, with me chasing it. I’m betting it leaks air somewhere because it was not put together right.

I ordered a new piston and cylinder kit (353 piston and removable transfer caps) along with a rim sprocket. The coil appears to be unlimited, so a new one is not needed. I will start working on it this weekend. I will be porting it like I did the other one, but this one will have .02 squish and the flat top piston. Ignition timing will be set to 28*.
 
Update:

The cylinder might be junk. As it turns out, the transfer cap screw are stripped out, and the cylinder is gouged and scratched from some grinder happy factory worker. I sent two emails and left a phone message with the company it was purchased from. I will see what they say.

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The cylinder kit is going back and I am getting a new one.
The company was very friendly and is sending a return label.
Now I just have to wait for parts again.
 
A long awaited update!

The new cylinder was in good shape, so it got the full treatment. The saw is together and running strong!

It has a 346 cylinder and a 353 piston. It turns pretty fast. I don’t have a tach, so I don’t have a solid rpm number, but it’s up there.

It cuts like a rabid beaver. I will be getting some video in the next few days.
 
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What was the deal with the silicone? Was the PO trying to fix a stripped muffler screw or something? Cracked my 350's body at the fuel tank but finally found another. Love 'em
 
This is the second saw I have rebuilt after a shop “fixed” it. Both were 350’s, and both had silicone everywhere. It was even stuck in the spark plug.