Can Anyone ID this piston???

[Cantdog]

This piston came out of a Jonsereds 521E. It is not supposed to be there......I thought I knew what pistons fit these 49cc saws.....not many options other than OEM.....Northwoods sells a crowned single ring 44MM reproduction piston for the 49SP that will work with a little help. OEM 52/52E/521E is a crowned two ring piston. But this piston is a flat top 44MM piston with a 10 MM wristpin....Someone made a bushing to adapt the wristpin to 12MM same as the OEM bearing, but left out the two thrust washers that center the cod rod to the piston. Anyway this is not going back in...I have a NOS P&C but would like to know what the heck this thing is supposed to fit. This piston has no markings/stamps or casting numbers what so ever...except an arrow pointing to the exhaust side. The only thing I can think of is an aftermarket piston for a 49 Husky. What say Yea???? Any ideas???

 

[Brettl]

Have you cross referenced Stihls? Some am positions made for Stihl will fit Jred according to a post I read. I'll try to find the post.

 

[Adirondackstihl]

Looks like a VEC for a 350

 

[Big_Wood]

did it run?

 

[cgraham1]

did it run?

I know, right?

I'm guessing the compression was lower than it should be, since the factory piston is domed, and this one is flat topped. But, then again, I'm not very smart.

 

[Big_Wood]

I know, right?

I'm guessing the compression was lower than it should be, since the factory piston is domed, and this one is flat topped. But, then again, I'm not very smart.

if it ran with low compression it might have felt clapped out but i'm used to that so i'd run it

 

[cgraham1]

if it ran with low compression it might have felt clapped out but i'm used to that so i'd run it

Yeah. Me too. Been running a clapped out 7900 lately.

 

[Big_Wood]

Yeah. Me too. Been running a clapped out 7900 lately.

i've been remoddding mufflers for more outlet just to try make up for the clappedoutness

 

[watsonr]

clappedoutness

New word...

 

[Big_Wood]

New word...

yes, my phone even has it in it's dictionary now

 

[Cantdog]

Looks like a VEC for a 350

I believe you're right............looks identical and with no markings it's most likely a VEC......Thanks!!!

 

[Cantdog]

did it run?

It had run but not by me.......nice looking saw......but many hidden problems and alterations from stock.....

 

[Cantdog]

I know, right?

I'm guessing the compression was lower than it should be, since the factory piston is domed, and this one is flat topped. But, then again, I'm not very smart.

Yes probably quite a bit less comp.......felt light on the pull......not bad just not as much resistance as I would expect, but didn't do a comp test. They did eliminate the cyl base gasket....but those are only about 0.006"-0.007" crushed so I doubt that made up for the loss of crown......

 

[Cantdog]

It had run but not by me.......nice looking saw......but many hidden problems and alterations from stock.....

There are and will be more pics in the Jonsereds sticky......very interesting saw.....not as good as it looked....but interesting....