Jonsered 590 rebiuld -PIC HEAVY-

[Arrowhead]

I picked up a Jonsered 590 awhile back. I decided to go through it 100% because I plan on using it quite a bit. It's basically a Partner 500/5000 series. It's a closed port 51cc. I finally got the last of the parts in that I needed to finish it. It really cleaned up nice under the massive amounts of crud that was on it.

I'll be posting pics probably over the next day or so.

The bearings and case gasket checked out fine, so I did not split the case. The one seal had a very tiny air leak, so I replaced both seals.

Removing the seal

The seal is out

New seal in place

Other new seal in place

Worm gear in place

New oil pick ups

This shows how the pump works, the pickup with the screen fits into the tank, and the other goes up towards the oil hole.

The pump is in place

 

[Arrowhead]

Pump cover back in place

Top view

I've never seen a flywheel with 2 key slots. I did not realize it when I pulled it. I used the one I think is correct, my luck I'll have to use the other.

Coil and flywheel back in place

Piston and cylinder

New intake sleeve and new impulse grommet

Piston back in place with new ring

 

[wigglesworth]

Hmmmmm....looks good Ed. That's gonna make a nice saw. Them 51cc top end's look strikingly familiar......

 

[SawTroll]

Yes, it looks really good! :msp_biggrin:

 

[polardoo]

My Husky 44 has two keyways, maybe for points ign in different markets???

 

[dk27]

Arrowhead
any chance You have the measurement of that piston?

 

[Arrowhead]

Checking the squish.

I was using .028 solder, it never even hit it, that's with no gasket. Depending what my compression ends up at, I may end up milling the cylinder or case.

A thin layer of Ultra Copper... no gasket.

Intake, carb and switch mounted.

Side air cover mounted

New AV parts

 

[Arrowhead]

Arrowhead
any chance You have the measurement of that piston?

Besides it being 45mm no. Did you want height and other measurements? If I go back in to mill the jug I can take them.

 

[Arrowhead]

My Husky 44 has two keyways, maybe for points ign in different markets???

Yes, that could be. I noticed when I was mounting the coil, there was an extra set of mounting holes also.

 

[Harold W]

590

Great rebuild!! Very interesting about the Squish!

 

[PB]

The flywheel should be on the key way labeled with a number 5.

 

[Arrowhead]

The flywheel should be on the key way labeled with a number 5.

Thanks , That's the one I put it in.

 

[Mastermind]

Great thread. I've yet to delve into the Jred world...

 

[Arrowhead]

I port matched the muffler to fit the exhaust port.
I did a mild port job to the saw. I could have went much more, but that will be on another saw.

I modded the muffler and installed it.

Getting closer to finished.

 

[dk27]

Besides it being 45mm no. Did you want height and other measurements? If I go back in

Nope
The 45 mm was all I need
trying to positive i.d. a j'red I have.
sticker on the case says 490, metal tag says 590.
Goodluck with the rebuild.

 

[Arrowhead]

A view of the air filter. Kind of a strange set up, the choke flapper is inside the filter.

The last of the covers are on.

 

[Arrowhead]

The saw is complete. :msp_smile:

 

[Arrowhead]

After about ten minutes run time, I let it cool and checked the compression. I was pretty amazed, I don't think I will be milling the jug. LOL

The saw flat out screams. It still had a hint of four stroking at 14K rpm. I fattened it to about 13,000 until it breaks in. For only having a few minutes on it, you can really lean into it. The chain is 3/8". I will try to put up a video tomorrow.

 

[Modifiedmark]

Great thread. I've yet to delve into the Jred world...

Neither has Ed really, hes working on a red Partner!

After about ten minutes run time, I let it cool and checked the compression. I was pretty amazed, I don't think I will be milling the jug. :rock: LOL

The saw flat out screams. It still had a hint of four stroking at 14K rpm. I fattened it to about 13,000 until it breaks in. For only having a few minutes on it, you can really lean into it. The chain is 3/8". I will try to put up a video tomorrow. :cheers:[/QUOTE]

Not surprising on the compression after looking at the picture of the combustion chamber, it looked pretty small.

Nice job and a interesting thread. I have never been that deep into one yet.

 

[dk27]

checked the compression

I ended up with about the same
Quite suprised too say the least