What's inside the Might O Ninety?

[blsnelling]

I've got a Lightning and a 090 but have never had to go inside of them like this. I picked up this 090 last night and decided to go through it completely. It didn't need everything I'm doing to it, but I wanted to check it out. I thought some of the rest of you might like seeing inside the beast, so took pictures along the way.

The saw started and ran fine before disassembly, but it was VERY dirty. Overall, it's in excellent condition. All it really needs is a set of rings, and a couple clutch shoes. The piston is good and the bore looks like new. The crank and bearings are good as well. The carb worked fine, but got a kit anyway. The orange parts had been resprayed and red, green, and blue paint were plattered all over the entire saw. Lots of cleanup work here.

I didn't get a pic of the saw before I started tearing it down.

 

[blsnelling]

 

[blsnelling]

Time for a serious bath!

This is compliments of the HF ultrasonic cleaner. I did no precleaning of any kind, just dropped it in the cleaner!

I bought all these gaskets last year in antisipation of the Lightning, but didn't need them. I had everything except crank seals. I wish I had bought them too now. So I'll be waiting for seals and rings to complete the reassembly.

Inside the fuel tank.

I was surprised to see that P&C design is just like most other pro Stihl saws, very modern looking.

 

[blsnelling]

Flywheel side crankcase half. I removed the studs so that I could properly clean up the mating surface.

PTO side.

Interesting crank bearings. Both sides have two needle bearings.

Studs back in.

Crank setting in the PTO side.

 

[blsnelling]

Inside the oil tank.

 

[blsnelling]

Sandblasted, then cleared to keep out corrosion.

Two of the little bolts twisted off and had to be drilled out and tapped.

 

[blsnelling]

Post away. That's it for now, until I get parts.

 

[7oaks]

Brad...

Thanks for posting these great pics. This is the project, of your's, that I'll be paying the most attention to. Looking forward to the progress and might have some questions in the coming days if I don't understand something.

 

[blsnelling]

What would be acceptable piston clearance in a 66mm bore?

 

[cpr]

Congrats on another 090.

Geez, that saw is a TANK. What a beast. Someday...

 

[mtngun]

Thanks for the pics, Brad.

That thing is built like a tank ! ! !

Impressive demonstration of the ultrasonic cleaner. I want one.

 

[blsnelling]

Geez, that saw is a TANK.

That thing is built like a tank ! ! !

It weighs as much as one too!

 

[BigE]

Nice post, Brad.

It's good to see you're putting that HF USC to work already! Are you running simple green in that?

 

[blsnelling]

Are you running simple green in that?

Yes. This thing will make the water so hot that it burns your hands to remove parts from it. So far, it gets a big thumbs up!

 

[gemniii]

Chainsaw P_O_R_N!!
looks great!!
When are you going to sell it?

 

[thomas72]

Looks good. The 090 seems to be in good mechanical condition.

 

[blsnelling]

When are you going to sell it?

When I get it back together Trust me, if I didn't already have one, it wouldn't be going anywhere!

 

[leeha]

Great thread Brad,
I like these oldie saw rebuilds.
I think you would be ok with 4 to 5
thou piston clearance, But i don't
have a manual.
I'm surprised at the flywheel side bearing,
Looks like just a small needle bearing.


Lee

 

[pioneerguy600]

Did any of the ports get massaged? Old hawg is in good shape, cleaned up real nice.
Pioneerguy600

 

[blsnelling]

Great thread Brad,
I like these oldie saw rebuilds.
I think you would be ok with 4 to 5
thou piston clearance, But i don't
have a manual.
I'm surprised at the flywheel side bearing,
Looks like just a small needle bearing.


Lee

I've got .008" clearance. Think that's ok? It sounded fine when I ran it. It's in good shape. It will definately need rings though.

Did any of the ports get massaged? Old hawg is in good shape, cleaned up real nice.
Pioneerguy600

No porting.