Revamping A 3120 From Alaska

[Mastermind]

Here's a saw that's done a bit of traveling........all the way from Alaska to visit my little backyard shop.

We didn't take any before pics.......but here's a few pictures of him with his crank hanging out. :msp_ohmy:









Sorta needed a piston......more about that later.

 

[Mastermind]

Jon is getting the case half ready to drop in the bearings here.......he's found that starting out heating the bar pad first makes it go quicker.





Pretty simple setup.......but very effective.



Slid right in......



After a few minutes the bearing will pull enough heat out of the case to allow the crank to slip in....

 

[Eccentric]

opcorn:

 

[Mastermind]

Now to heat the other half.



Even though we are using a new OEM case gasket we still coat the gasket with Loctite 518.



Centering the crank......



And there it is.

 

[Mastermind]

Pretty clean saw here.........very good condition.

 

[Mastermind]

Coming right along. I wish I could port one as fast as Jon can do the bottom end.



There's the old piston.......more about that in a bit.







272 coil here......that makes these beasts unlimited.

 

[Mastermind]

Now for some tweaks.....

Here's the air filter base. It needs some work.



That's better....

 

[Mastermind]

Now for the muffler.



Sawed in half.



That's a lot of BS.



And that's with the BS removed.



Now to put it back together.





And fix some un-needed holes.

 

[Mastermind]

 

[Nitroman]

Man that saw is clean. Never knew all that stuff was inside the muff.

Guys, this is why it is sometimes better to just lay out the long green and smile.

 

[Mastermind]

So far Jon has been having his way with Roger's saw.....now I get to play with it a little while.





OK here's that piston again......



Now here's what happened to it.

No bevel at all on the ports. I don't know if they just forgot or what.....but it sure ruined the piston and the rings.

 

[Nitroman]

This thread is getting me all hot and bothered.

 

[Mastermind]

Now I get to try out a new boring bar on a 3120 jug........them jugs is cheap anyway. :msp_unsure:







Seems to be cutting something outta there.



Now to cut the base...



And the cylinder extension.

 

[young]

.....
No bevel at all on the ports. I don't know if they just forgot or what.....but it sure ruined the piston and the rings.
...

"they" meaning what? husky?

 

[Nitroman]

"they" meaning what? husky?

The fellow who originally worked on the saw a long while ago. The name is totally unimportant, he's long since retired.

 

[Mastermind]

We have a little interference issue here....



But that ain't no problem.





Now to figure out the port timing numbers we should use. But I'll just keep that stuff outta this thread.



Last pic of the night......so far all I've done is bevel the port edges to keep from scratching the new piston up. This is how it was when we tore it down.

 

[Nitroman]

So far Jon has been having his way with Roger's saw.....now I get to play with it a little while.

Heh-heh...innuendo. I like it. A lot. Heh-heh....:blush:

Open it bey-beh!! Open it like the Red Sea!!!! HAHAHAHAHAHAHA!!!! Ahem...sorry. Got a little carried away.

 

[LowVolt]

What are you using to center the crank? From what I have read I do not recall centering the crank. I just recall that after you assemble the bottom end the crank may be hard to turn so you need to smack the ends of the crank with a brass hammer. This centers the crank/bearings everything and enables it to turn freely. Can you shed any light? I have two ms361's I am stripping down to get cracks in the cases welded up. These are my first complete rebuilds.

Btw, awesome build thread you got goin on here.

 

[Yukon Stihl]

Hey that's my neighbors saw
I like the old craftsman tool box,my Dad gave me his years ago,i went and painted it red and covered it with stickers.Wish it was still stock.
Love the thread.
Thomas

 

[7sleeper]

Thanks Randy! As usuall eye candy at it's best!

Thanks!

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