2050 jonsered,piston scored need advice

[ccrain]

The jonsered 2050 turbo i went and bought today the top of piston is scored but just above piston o ring.The cylinder walls look fine and smooth all around, or is there damage not seen by the human eye.Hopfully a piston kit and she will run.The gas I dumped out had a little blue color but looked like mainly gas.

 

[Brian VT]

Is the piston melted or is it gouged from a foreign object ? (carbon, plug tip, circlip, etc.)
You said the cylinder looks good to the eye. Is that looking from the bottom or just looking through the ports ?
If you haven't taken the cylinder off, I would recommend doing that and run your fingernail over anything that doesn't look normal.
Often any ridges that your fingernail catches on is melted aluminum from the piston and can be removed with muriatic acid.
If the coating of the cylinder is scratched, then the cylinder will need to be replaced.
Before running it, you'll need to find out why the piston melted (lack of fuel or too much air, usually) or it will happen again.

 

[ccrain]

Ok,the reason why it scored is the previous owner run it with straight gas.

 

[ccrain]

Just went and feeled up in the cylinder,felt one snag on my finger nail,not notciable but i felt it.

 

[Brian VT]

not notciable but i felt it.

???
I assume it's on the exhaust side. Is it above the port or below ? Does it seem to be on the cylinder's coating (aluminum from the piston) or scratched into the coating ?
Posting pics might help.

 

[pops21]

It has aluminum transfer on the cylinder wall. No doubt about it. If you felt it with your finger nail then its there. You know if you want you could send me the cylinder. I could clean it up and send it back to you. Heck for that matter I could meet you lets say at the upward RD. exit on 26. The one that has cracker barrel. I could have it done and back to you in a weeks time or less depending on when we could meet up to give it back to you. Then all you would have to do is put it back together. :smile2:

 

[ccrain]

If it helps you can feel it just by running the finger over the spot.The very first time i checked cylinder out did not take my time.Pops21 i might just have to takeyou up on your offer.Cheapest would be to mail it for me and pay you to send it back.

 

[SawTroll]

If it helps you can feel it just by running the finger over the spot.The very first time i checked cylinder out did not take my time.Pops21 i might just have to takeyou up on your offer.Cheapest would be to mail it for me and pay you to send it back.

You still will need a new piston, of course!

 

[Carl Anderson]

Please be sure to keep us posted, including pics of course! My first saw was a 2050 Turbo, nice saw. I gave mine to a buddy whose saw was stolen after I bought my new 346. I just saw him the other day and my old saw was right there riding shotgun in his truck, made me happy to see it. He said it's running strong but still won't idle. Anyway, good luck with yours, I'll be looking for your updates!

 

[ccrain]

Will do carl.My dad has a jonsered (well since ive started collecting saws hes gave it to me).Its a model 920 and is a beast,he bought it new in the early 80s when he had a saw mill.This hobby is beginning to be really fun.I also collect coleman lanterns,as i have been restoring them for a year but chainsaw is a new one.I like to hear something run after sitting a long time were lanterns they do not acutely run,but guess i will collect both.

 

[pops21]

Thats fine with me. I'm sending you a pm right now. I'm in the christmas sprit. So merry christmas.:msp_thumbsup: Keep collecting chainsaws they are really addicting. All I ask is for you to remember this and the next time someone around you is in need, then to help them.

 

[ccrain]

heres what the piston looked like

The cylinder

 

[Brian VT]

Ouch. That's pretty serious.
I hope the cyl. cleans up ok. If it does, you need to find out why it cooked before you run it with a clean cyl. and new piston and rings.

 

[pops21]

Looks like you need a new filter. I see saw dust in the intake on the cylinder. Also you might need a new carb boot. That looks like it might have been killed by saw dust and maybe just maybe straight gas. But I'm kinda thinking saw dust.

 

[Axlerod74]

These are great saws. I think the Husqvarna 49 uses the same piston and cylinder. Not much aftermarket available and OEM for these is expensive. Worth fixing for sure.

 

[ccrain]

The saw dust in the cylinder is from when i layed the cylinder in a box i put the rest of the motor on top and there was some sawdust on the motor/case,and it fell down in there.

 

[SawTroll]

Ouch. That's pretty serious.
I hope the cyl. cleans up ok. If it does, you need to find out why it cooked before you run it with a clean cyl. and new piston and rings.

Yes, (to the OP) don't replace anything before you know why the original parts failed - if not it is very likely that it will happen again! :msp_wink: