Getting into a used 046

[NeoTree]

Thats odd.... your measurement from center to top,is 0,413 in/1,04 mm higher than my 064 piston?? that don´t make sense

is it because its a usa/euro version??

I'm not sure. My piston is a meteor brand piston, so it could be a brand thing. The specs for mine are on Baileys website. I measured against my oem piston and came up with the same numbers as advertised, off my only .0002"

I worked on squish last night, by memory here are the numbers,

My stock squish was .054"
Base gasket was .016"
Removing the base gasket and using a .004" peice of alum as gasket I come up with, new squish of .042"
To acheive .019" squish I need to leave .023" on the crown around the popup
I've got .059 to work with...
.059-.023 leaves me with a .037" pop-up and a upper ring land that's 1.03"

pics later

 

[mtngun]

Since it is off center I cannot really turn it on the lathe

I have yet to try this, but if I ever need to turn an off-center pop-up, I was thinking to make a TW-style piston fixture, and then use a 4-jaw to set the fixture off-center. Of course, the piston would have to be indexed very carefully with respect to the off-center pop-up, but that's true when using a mill, too.

Sounds like you have a good plan.

 

[NeoTree]

I have yet to try this, but if I ever need to turn an off-center pop-up, I was thinking to make a TW-style piston fixture, and then use a 4-jaw to set the fixture off-center. Of course, the piston would have to be indexed very carefully with respect to the off-center pop-up, but that's true when using a mill, too.

Sounds like you have a good plan.

Thats what I was thinking too. I would have to build my machining skills a bit more to give it a try though.

 

[PLMCRZY]

Did you paint your rear handle/tank assembly?

Btw looks really good!

 

[John R]

That is a hell of a big carburetor for that saw.

 

[NeoTree]

Ya the handle is painted, along with rest of the saw, the epoxy paint is hard as nails now.

The piston's going under the cnc tomarro finally! We decided to hop it up a bit more

 

[farrell]

is a used 046 in great shape and running order worth $275

 

[MS390]

is a used 046 in great shape and running order worth $275

thats the price for a non runner in Europe:msp_bored:

 

[NeoTree]

My buddy cut the piston to my specs today. He wouldn't let me pay him, but that's allright, I left him a bottle of Jack Daniels on his doorstep for when he gets home

Heres my mold of the combustion chamber I made

Trust me, it fits

 

[NeoTree]

Oh yeah, I still gotta cut the skirts a tad tomarro on the lathe, he was a bit rushed with production.

 

[mtngun]

In a perfect world, the edge of the pop-up would be a gentle angle. He sure did a good job of matching your mold, though. :rockn:

 

[NeoTree]

In a perfect world, the edge of the pop-up would be a gentle angle. He sure did a good job of matching your mold, though. :rockn:

I agree, he decided to go with a 32nd radius on it, which left about .010 of vertical flat on the popup... If I really wanted to screw with it I would have cut the popup about .060 wider diameter with a 5/16 radius button mill, but it would have to be pretty tight tolerance. I would of ended up with a tad more displacement, and probably a real good mixing squish.
This being my first though i thought i would keep it simple.

 

[epicklein22]

Nice job so far. That pop-up is slick looking.

 

[NeoTree]

thanks man

 

[mdavlee]

That's a slick looking popup.

 

[NeoTree]

hmmm,,,we may have a slight issue:msp_drool:

any suggestions? this is cold, piston just installed with cyllinder lubricated well. Still, may have to add a thin base gasket to tone it down, squish would still be good. This is a work/PLAY saw sooo... more work to be done for sure!

oh yea, lol, I plugged the decomp too, this thing is "fun" to pull over like this

 

[epicklein22]

I would run it, the assembly oil can give false readings.

That might be baddest saw in Portage County when it is done. hahaha I guess I need to step my game up!

 

[NeoTree]

I would run it, the assembly oil can give false readings.

That might be baddest saw in Portage County when it is done. hahaha I guess I need to step my game up!

Lol, it might be the baddest saw for a couple minutes, I'm thinking aviation fuel for starters just to be safe.

I guess I'll try running it for a bit, and if it doesn't grenade I'll port it before the GTG.

 

[Mastermind]

Wow Justin, that's some compression! You might "rinse" this assembly lube out with some mixed fuel and check it again, but I would say it's still gonna be too high, that's easy to fix though. What would it cost to get a piston like that???

 

[NeoTree]

Wow Justin, that's some compression! You might "rinse" this assembly lube out with some mixed fuel and check it again, but I would say it's still gonna be too high, that's easy to fix though. What would it cost to get a piston like that???

Oh man I dunno about a price. As far as time, I've probably got 5 hours running numbers, an hour or two indexing, setup, and machining off the skirt bottoms and widening the inner pin bosses. Also my buddy probably had a good hour or so too doing the top.

This would be alot easier though if the combustion chamber was a normal concentric circle, then I could of done everything but the pin bosses easily on the lathe.