Husqvarna 268 open port

[nenicu]

Hello. I am working on a open port Husqvarna 268. I have to change the piston snd i can't find the right piston. Can i use the windowed piston of a 268 XP? I was looking at the Dolmar 7900 design [ big open transfers and windowed piston] and i was thinking to put the 268 XP piston. What do you think. Thanks.

 

[erikvr]

It will work fine with a windowed piston, a closed port cylinder however will not work optimal with a non-windowed piston. http://www.arboristsite.com/community/threads/windowed-piston-versus-non-windowed.75769/

 

[Chainsaw Jim]

It should actually perform better with the windowed piston. The Windows allow air flow through the piston which helps cool it, plus the needle bearing will lubricate more efficiently.

 

[briantutt]

I just got the right piston kit from llrdbrn off the fleebay for a 268. Lee has more.

 

[briantutt]

I did notice on the two 266SE both pistons have a window. The cylinders for both are constant diameter full length. On the 268 and 162SE I also have apart both pistons have the open skirt and the cylinders get larger near the transfer port area. So I assumed a windowed piston wouldn't work in the 268 cylinder. But I really don't know and based on the above comments it might work.

Brian

 

[Chainsaw Jim]

I did notice on the two 266SE both pistons have a window. The cylinders for both are constant diameter full length. On the 268 and 162SE I also have apart both pistons have the open skirt and the cylinders get larger near the transfer port area. So I assumed a windowed piston wouldn't work in the 268 cylinder. But I really don't know and based on the above comments it might work.

Brian

There's a lot I don't know about chainsaws, but it just doesn't sound right for a cylinder bore to be barrel or cone shaped like you mention unless it is worn out or has been improperly honed from a previous rebuild.

 

[Big_Wood]

It will work fine with a windowed piston, a closed port cylinder however will not work optimal with a non-windowed piston. http://www.arboristsite.com/community/threads/windowed-piston-versus-non-windowed.75769/

every dual port cylinder i have ever seen closed port or open runs better with a windowed piston

 

[nenicu]

Thanks . I have experimented whith a open port Partner 540[Husqvarna 55 cylinder and piston]. It works better with a windowed piston[Jonsered 2055 piston 46 mm]. In this case the cylinder has double open transfers on each side, so i was thinking if an windowed piston is gonna work, then i remembered: The old piston for Dolmar 7900 was like the H 268 S/k piston, the new piston is windowed.[As seen on Arboristsite].