Husqvarna 350 rebuild issue

[edr]

Hello, first post here, but this site has been SO helpful with all my saw questions! Thanks!

So I am rebuilding my original first saw ( Husky 350) new everything ( crank. piston, cylinder, ect) I went with the big bore 45mm piston which has 2 rings on it instead of the single ring on my original piston. My problem is that i get the piston and rings into the cylinder (squeezing rings with fingers) and it goes in about a quarter inch past the rings and then stops... i cant get it to slide in any further it just sticks there. It is then hard to get piston back out as well VERY tight. Piston slides nicely into and out of cylinder without rings installed.... I'm not sure what it is sticking on --- any thoughts? FYI -Piston / rings / cylinder came together in kit

 

[ballisticdoughnut]

Make sure you’ve got the piston installed correctly. Ring locating pins should be facing the intake port.

 

[Fordsoll]

Check ring gap although it should be good from factory and look for burrs on ports. Did you hone the cylinder?

 

[Chevboy0167]

What brand big bore kit? 2 rings??? I built 4 of these series saws the last 2 yrs and have used Meteor, Hyway and an OEM 346XP kit. None have 2 rings on the piston. This includes the bigger bore cylinder on the 350 platform.

Sounds like to me, you have ring getting hung up on the intake or exhaust port... maybe even a transfer port. Depends on where the rings end gap meets...

 

[edr]

Check ring gap although it should be good from factory and look for burrs on ports. Did you hone the cylinder?

I did not hone --rings seem fine and cylinder is smooth

 

[edr]

rings are facing intake and piston arrow facing exhaust --- ive tried to get it to seat down a bunch of times with same results

 

[edr]

ordered new set of rings ---

 

[rupedoggy]

Got the rings on upside down?

 

[edr]

Got the rings on upside down?

they are in so the fit around the pin in the groove of piston...

 

[singinwoodwackr]

Pics will help.
You should get one of those piston instal kits. They are cheap and eliminate issues from trying to compress rings with just your fingers.
I have a 350 in a box, all cleaned up and ready to assemble

 

[Chevboy0167]

Another possibility is that the cylinder and or piston are out of round... getting wedged together. You would need a bore gauge and micrometer/caliper to confirm or take them to a machine shop and let them do the checking for a few bucks.

 

[a. palmer jr.]

My guess is something to do with the rings, either upside down or hanging up on the locating pin when piston is being inserted into the cylinder.