Got burnt buying an 026

[Woodchuckr]

Top of the piston/Cylinder looks like a needle bearing came apart on the rod, make sure your lower one isn't missing any.

That’s what i thought, looked at them first. All are there.

 

[stihltech]

Anything less than a complete diagnosis will leave a question and another ruined piston. Get a good look at the bearings, all of them. I bet on a cage failure. Move the rod side to side and check the cage on the crank. Also rod up and down play.
No movement up and down , in and out, or sideways allowed on crank side bearings.
And if this would have had metal cages, the piston and cylinder would have large gouges. Plastic cages give it a chance to survive.

 

[ZeroJunk]

The cage on the other bearing looks like plastic. Would it do that kinda damage?

Check the piston and make sure both ring stop pins are there.

 

[Woodchuckr]

Looks more the length of a ring stop pin.

Both pins are still there, no broken rings. Both pin circlips are full size. But you got me thinking. Only thing that size and shape that looked odd was the cotter pin on the air filter. Choke flap was not seating right even with the filter off and pushing the arm with your finger. That Cotter pin was only half way through and it’s ends weren’t bent to lock it. But….. if you snipped off the ends of the old one to get it out you never know where the pieces ended up. They would match the marks on the piston.

 

[av8or3]

Spark plug electrode

 

[Woodchuckr]

Anything less than a complete diagnosis will leave a question and another ruined piston. Get a good look at the bearings, all of them. I bet on a cage failure. Move the rod side to side and check the cage on the crank. Also rod up and down play.
No movement up and down , in and out, or sideways allowed on crank side bearings.
And if this would have had metal cages, the piston and cylinder would have large gouges. Plastic cages give it a chance to survive.

Yeah I am going to take a real good look at the big end. It felt good and no slop. Going to get the magnifying glass out and look for a missing piece of cage on it, top rod bearing fully intact. I fully agree with the full diagnoses, had a 503 rotax eat a piston that we had to call snow dust ingestion. Why only one piston? Aerodynamics of the air box and cowling and the the guy I was following was on the same side of me that the piston failed. Lol, was nervous first couple rides. I don’t follow close in snow dust anymore and she still runs good 10 years later. You would never know it has a bigger piston in one hole.

 

[Woodchuckr]

Spark plug electrode

It was the same plug before and after the damage and still looks to be all there.

 

[Woodchuckr]

Both pins are still there, no broken rings. Both pin circlips are full size. But you got me thinking. Only thing that size and shape that looked odd was the cotter pin on the air filter. Choke flap was not seating right even with the filter off and pushing the arm with your finger. That Cotter pin was only half way through and it’s ends weren’t bent to lock it. But….. if you snipped off the ends of the old one to get it out you never know where the pieces ended up. They would match the marks on the piston.

Yeah I am going to take a real good look at the big end. It felt good and no slop. Going to get the magnifying glass out and look for a missing piece of cage on it, top rod bearing fully intact. I fully agree with the full diagnoses, had a 503 rotax eat a piston that we had to call snow dust ingestion. Why only one piston? Aerodynamics of the air box and cowling and the the guy I was following was on the same side of me that the piston failed. Lol, was nervous first couple rides. I don’t follow close in snow dust anymore and she still runs good 10 years later. You would never know it has a bigger piston in one hole.

Had a minute to be an inspector, unless this cotter pin is made different than all others i have used I would safely say we have a 100% diagnoses. Rod bearings all looked fully intact so I had a peek at that cotter pin. First pic is exactly how the pin was, I was going to pull it out and do it proper before I even started the saw the first time. Who would think a cotter pin outside the air filter would be an issue, even if the pin fell out, big deal the choke won‘t operate right.

Once I get the bearings I’ll check the squish but meantime any experienced 026 members chime in on if this saw would have survived without the base gasket?

 

[Woodchuckr]

Forgot the pic

 

[Woodchuckr]

Had a minute to be an inspector, unless this cotter pin is made different than all others i have used I would safely say we have a 100% diagnoses. Rod bearings all looked fully intact so I had a peek at that cotter pin. First pic is exactly how the pin was, I was going to pull it out and do it proper before I even started the saw the first time. Who would think a cotter pin outside the air filter would be an issue, even if the pin fell out, big deal the choke won‘t operate right.

Once I get the bearings I’ll check the squish but meantime any experienced 026 members chime in on if this saw would have survived without the base gasket?

I probably shouldn’t say 100%, it’ll probably bite me in the backside.

 

[Woodchuckr]

I probably shouldn’t say 100%, it’ll probably bite me in the backside.

Looked at some air filter pics, seems I may have jumped to conclusions. never seen a pin with one leg that much shorter. Have to keep looking.

 

[Aknutter]

With the gasket missing and dirko used , it was already apart at least once. Probably cleaned it up a bit and got it to run for a bit, put on the bay and sold it... Now it's your problem and your dealing with it.

 

[SteveSr]

I probably shouldn’t say 100%, it’ll probably bite me in the backside.

I wouldn't bet on the cotter pin. First it is OUTSIDE the air filter. Second, most cotter pins come with a short leg making it easier to separate the two ends.

 

[Woodchuckr]

I wouldn't bet on the cotter pin. First it is OUTSIDE the air filter. Second, most cotter pins come with a short leg making it easier to separate the two ends.

Yeah its not the cotter pin. All the ones i have used have a shorter leg but not that short. I looked at pics online of filters, the one leg is a lot shorter.

 

[Woodchuckr]

With the gasket missing and dirko used , it was already apart at least once. Probably cleaned it up a bit and got it to run for a bit, put on the bay and sold it... Now it's your problem and your dealing with it.

Yep, called up pay pal. Filed a misrepresented product claim, goes back and forth a bit and got my full refund and keep the saw.