Stihl 039

[066 redeye]

Hi all.Might be able to get an 039 cheap.Piston scored,ring stuck in groove,no compression.Don't know cylinder condition yet.Is this saw worth fixing?Would do vac/press test before strip down to prove other faults.I can get a Tacsum kit for $125 (Aussie).Are these any good?Wouldn't go OEM as too dear Down Under.
Cheers,Chris.

 

[dahmer]

I ain't a Stihl pro but I just picked up a used 039 that runs good. While imho it isn't as good as my Makita 6401 it's still a good saw. A Stihl junkie might give you a different view.

 

[Jon1212]

A serviceable 64cc unit, that will put a lot of wood on the ground, in short order. A 20" bar and chain set up balance very well.
Open up the muffler, and they are pretty snappy.

 

[dahmer]

A serviceable 64cc unit, that will put a lot of wood on the ground, in short order. A 20" bar and chain set up balance very well.
Open up the muffler, and they are pretty snappy.

Like I said, you need a Stihl pro, I forgot to mention the mm and retune.

 

[fearofpavement]

A muffler mod makes a huge difference on this series of saw. And the bigger the model of 1127 saw, the more difference the mod makes. The 039 is a good saw. I've used them a lot. U usually repair them with a Farmertec kit from Huztl. If you get it, pull it apart and assess it before you order parts so you know what you need. May be able to save the cylinder. I'm hoping to get hold of an MS310 tomorrow.

 

[Jon1212]

Like I said, you need a Stihl pro, I forgot to mention the mm and retune.

You give me too much credit. I know just enough to be dangerous.

@Mastermind did this muffler alteration. Earplugs are strongly advised.

 

[Terry Syd]

Mine's a little ripper, but I've done a bunch of work to it. You may want to see if you can salvage the cylinder, if so, then there is a high compression piston that will be coming available -

http://opeforum.com/threads/stihl-m...n-kit-to-be-sold-soon.6027/page-5#post-463833

 

[066 redeye]

Thanks all.Done a few 066 builds.Haven't done a clam shell but dad has.
The bloke may not give it up yet,see how I go.
Cheers,Chris.

 

[Jon1212]

Thanks all.Done a few 066 builds.Haven't done a clam shell but dad has.
The bloke may not give it up yet,see how I go.
Cheers,Chris.

Just tell the current owner it is an overweight turd, and you are doing him a favor by taking it off his hands. For the good of the community.

 

[Jon1212]

Mine's a little ripper, but I've done a bunch of work to it. You may want to see if you can salvage the cylinder, if so, then there is a high compression piston that will be coming available -

http://opeforum.com/threads/stihl-m...n-kit-to-be-sold-soon.6027/page-5#post-463833

Different carburetor, or did you modify the OEM unit?

 

[Terry Syd]

Different carburetor, or did you modify the OEM unit?

Yeah, I've got a modded Zama twin jet on it. I tried modding the HD-5, but the Zama worked better. I also dialed in the timing and have the 660 coil with the 4 degree retard for starting, with the de-comp it is an easy starting saw. The air filter is the biggest restriction to intake flow, so I had to make up my own filter. Since I had a spare 20" Husky Narrow Kerf bar in the shed, I did some creative work and put that on. These 'project saws' start taking on a life of their own, but this old beat-up 029 is now my go-to saw - it was suppose to be my 'loaner saw' LOL!

 

[Terry Syd]

Jon, if you want to try a modded HD on it, they work fairly well, better than stock anyway.

You have to isolate the high and low circuits as they are joined together. You have to push out the main discharge nozzle and plug the joining circuit with some GB Weld. Put the nozzle back in, then you have to drill a hole in the wet side to feed the low speed needle. Then increase the size of the auxiliary jet, I can't remember now, but I think I took the auxiliary jet (the brass jet) out to .35mm.

 

[066 redeye]

Just tell the current owner it is an overweight turd, and you are doing him a favor by taking it off his hands. For the good of the community.

A bloke give it to him for part payment for a load of wood,so might want some money back.Gee I wonder why he gave it to him??????
Cheers,Chris.

 

[Jon1212]

Yeah, I've got a modded Zama twin jet on it. I tried modding the HD-5, but the Zama worked better. I also dialed in the timing and have the 660 coil with the 4 degree retard for starting, with the de-comp it is an easy starting saw. The air filter is the biggest restriction to intake flow, so I had to make up my own filter. Since I had a spare 20" Husky Narrow Kerf bar in the shed, I did some creative work and put that on. These 'project saws' start taking on a life of their own, but this old beat-up 029 is now my go-to saw - it was suppose to be my 'loaner saw' LOL!

My MS390 is a 2002 that I've had since new. It's an early 390 from the changeover from the 039. It doesn't have a decompression valve.
It does have one of these stickers though.

Jon, if you want to try a modded HD on it, they work fairly well, better than stock anyway.

You have to isolate the high and low circuits as they are joined together. You have to push out the main discharge nozzle and plug the joining circuit with some GB Weld. Put the nozzle back in, then you have to drill a hole in the wet side to feed the low speed needle. Then increase the size of the auxiliary jet, I can't remember now, but I think I took the auxiliary jet (the brass jet) out to .35mm.

Fuel delivery witchcraft.....just as I suspected.

 

[Jon1212]

A bloke give it to him for part payment for a load of wood,so might want some money back.Gee I wonder why he gave it to him??????
Cheers,Chris.

I sure hope it wasn't a very large order of wood....

 

[Terry Syd]

Fuel delivery witchcraft.....just as I suspected.

The stock 029 and 039 use the SAME CARB. The same carb for 54cc and 64cc, that's 18.5% difference in displacement, yet the internal jetting is the same.

Here's how Stihl got around it, they set the 029 up for max revs a 12,500 and the 039 for 11,800 (I think that is right, it might be 11,900). What Stihl was doing was making the high speed circuit richer so that the fuel curve would extend down lower, so they could pick up more torque.

You mod the carb, you pick up more low end and can lean out the high speed needle to cut faster for limbing. My saw likes to cut everything at 11,000 rpm, but you can lean on the spikes without it bogging. That's with an 8-pin on a full comp .325 chain and 6 degrees of cutting angle.

If you want to try modding a carb, I'll walk you through it. You probably have a couple of carbs to work with so you can have a baseline to work from. Mod a carb, it works better so that is the new baseline, etc. etc.

 

[066 redeye]

Update,won't sell saw but wants me to fit new P/C.Haven't done clam shell so good learning curve for me.
Cheers,Chris.

 

[Fruecrue]

First clammy is definitely an experience.
Not too bad once you've done a few.
I have three I'm planning to sell and one just sold, all had to come apart.