Removing stuck cylinder on Jonsered 2051

[NPKenny]

I'm working on a Jonsered 2051 and cannot get the cylinder off. The piston looks scored on the exhaust side and really warrants further investigation. I've tried taps with a deadblow hammer, pulling from a vise, and using a rope through the plug hole to lift the cylinder.

I have removed 4 bolts from the bottom of the case and don't see any other attachment points or reasons why this jug shouldn't just slip off.

Any thoughts??

 

[greg409]

Was this your daily runner?

If not, maybe let it soak overnite with penetrating oil in the cyl.

Then I'd have someone (or something) suspend the saw by the cyl a few inches above a NON-HARD surface

Try tapping the top of the piston (thru the plug hole) with a wooden dowel, something that will not scrape the cyl wall.

The piston is toast, the cyl. may be salvageable.

JMO, I've not had one seized like that.

luck,greg

 

[mrnecsteve]

There are fittings (which commonly come with compression testers) which may enable you to connect a compressor to the
spark plug opening... is this a tool set in your possesion?

 

[ckelp]

you can apply heat to the piston though the exhaust port and see if that works
if it's above the ports you can make an adapter to a grease gun and pump it full till the piston moves
worst case take the angle grinder and cut the jug in half log ways
there's some tricks i'm missing..
also from my experience 95% of the time if the piston is stuck the jug is shot..

 

[NPKenny]

I got this saw in a non-running condition and have no idea of it's history.

Yes, I have an air fitting I can install in the spark plug hole, but I can't really see the merit of the compressed air here. I can't remove the intake boot to cover the intake without destroying it. I would also have to plug the exhaust port since the piston still moves freely.

 

[NPKenny]

also from my experience 95% of the time if the piston is stuck the jug is shot..

The piston is not stuck, which has me baffled as to why the jug is stuck to the pedestal.

BTW: Sorry for the picture... It turned out terrible.

 

[greg409]

I got this saw in a non-running condition and have no idea of it's history.

Yes, I have an air fitting I can install in the spark plug hole, but I can't really see the merit of the compressed air here. I can't remove the intake boot to cover the intake without destroying it. I would also have to plug the exhaust port since the piston still moves freely.

I apologize, I thought it was seized up.

You may have a broken piston so it'll move slightly, but hang up on a port.

If that's the case, you may have to remove the intake to see if it's hanging up there.

I asked if it was your runner, since often saws that sit for years may be simply stuck.

Unfortunately, as Ckelp said, you can always cut the cyl off

luck,greg

 

[hkusp9]

I had this exact same question about a month ago. All the same suggestions were offered and they were good suggestions.

What i actually did was attach an impact wrench to the flywheel or clutch and give it a few seconds with the impact wrench banging on the piston to get it unstuck and unfrozen from the bad spot between the piston and cylinder, i was then able to pull off the cylinder by hand.

 

[greg409]

I had this exact same question about a month ago. All the same suggestions were offered and they were good suggestions.

What i actually did was attach an impact wrench to the flywheel or clutch and give it a few seconds with the impact wrench banging on the piston to get it unstuck and unfrozen from the bad spot between the piston and cylinder, i was then able to pull off the cylinder by hand.

That would tend to scare me a little, maybe a rubber strap wrench on the flywheel, I think I'd be afraid to snap something off.

Plus, in this case, the piston moves and then hangs up, if I understand correctly.

luck,greg

 

[NPKenny]

Plus, in this case, the piston moves and then hangs up, if I understand correctly.

luck,greg

No, the piston doesn't hang up at all. It makes the full revolution with the flywheel. The cylinder is stuck to the pedastal (intermediate part between the cylinder and the bottom half of the crankcase)

 

[greg409]

No, the piston doesn't hang up at all. It makes the full revolution with the flywheel. The cylinder is stuck to the pedastal (intermediate part between the cylinder and the bottom half of the crankcase)

So the intake is attached if I remember correctly?

Is something hanging up on that?

The piston skirt will come to the bottom of the cyl (usually), maybe the rings are hanging up on material stuck to cyl?

I can't imagine anything else.

luck,greg

 

[NPKenny]

Upon further review... I missed a bolt that attaches the cylinder.:confused2: There are two bolts on the underside (front of cylinder on clutch side), one attaching the pedestal and one going all the way through to the cylinder. I had only removed the pedestal bolt. The jug slid right off.

Thanks for the help, guys. Sometimes you just have to go public in order to find the simplest solutions.