MS390 / 039 pop up piston

[Keith Gandy]

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Awesome!!

 

[Keith Gandy]

Nice build brother! I recently rebuilt this 039 with a meteor and is a nice runner

 

[drf256]

They are a damn good saw. Made fun of often.

 

[Keith Gandy]

They are a damn good saw. Made fun of often.

Al did u get the 036 cylinder I sent with John for one of your builds for Ambru84

 

[drf256]

Al did u get the 036 cylinder I sent with John for one of your builds for Ambru84

Not yet

 

[Keith Gandy]

Not yet

Ok he just showed up at my shop awhile ago and said its in the mail brother

 

[stihl_head1982]

They are a damn good saw. Made fun of often.

Have a number of them in the field. Rebuilt, some with meteor pistons and cleaned up cylinders, some with the older Chinese kits.
Plenty of hours on them with happy people running them. I'd buy a nice looking carcass and build one in a heart beat.

 

[RI Chevy]

I just recently sold my Stihl 029. I ran it hard for over 20 years. Much harder than it was intended for. Piston and cylinder looked brand new. It was a clean saw that served me well. I always intended to make it into an 039, but I now have all pro saws.

 

[stihl_head1982]

I just recently sold my Stihl 029. I ran it hard for over 20 years. Much harder than it was intended for. Piston and cylinder looked brand new. It was a clean saw that served me well. I always intended to make it into an 039, but I now have all pro saws.

029's that are well kept make good candidates for the upgrade, at least I think so.
Although I am with you on the "pro saw" up grade.

 

[Fruecrue]

Cross pop ups are in the Deal of the Day!
I ordered two more!

 

[Fruecrue]

Had a standard cross piston in the shop.
Same as what is in the saw now.

Actually heavier than the pop up piston!
Top of pin to top of piston is .605”

I’m excited now! I will gain compression, drop my squish .003” to approximately .025” and drop piston weight.

 

[RI Chevy]

Should make the saws faster and stronger, ehh?

 

[Fruecrue]

Should make the saws faster and stronger, ehh?

Should indeed!

 

[71dart]

Compression is an impressive 168 psi, please keep in mind what that plug looked like and how much oil is in he jug.
View attachment 97584

That's impressive. My oem 390 top end blows right at 140psi.

 

[Fruecrue]

That's impressive. My oem 390 top end blows right at 140psi.

Have you measured squish?

 

[71dart]

Yes. Squish is at .035".

 

[Fruecrue]

Got some video today.

16” .325 round semi-chisel in cottonwood.

 

[RI Chevy]

Looks good! How does it feel or compare to a ported saw?

 

[Fruecrue]

36” 3/8 on an 039?
Why not!
Probably won’t oil it, but...

 

[Fruecrue]

Looks good! How does it feel or compare to a ported saw?

These are before the pop up.
These saws are respectable stock with a muffler mod.