My 290-390 conversion thread

[Junk Meister]

No, I looked it up. It’s a black Stihl branded one specifically for these clamshells

Part #? Picture maybe. You guys got my curiosity going.

 

[STOVE]

Part #? Picture maybe. You guys got my curiosity going.

1127-893-2602


Mine is still in the mail somewhere

 

[jacob j.]

Still waiting on my 1127 ring compressor to arrive and I had a thought.

I’m constantly running my fingers over the inside of the ports to convince myself they are beveled enough. Would putting a ring in the jug and pushing it up be a solid test?

Did you previously slide the piston without rings into the cylinder? You might want to do that to ensure there's nothing hanging up.

 

[STOVE]

Stihl waiting on my 1127 ring compressor tool, however a coworker gave welding on the deflector a go. Looks like it will let some air out

 

[EFSM]

Stihl waiting on my 1127 ring compressor tool, however a coworker gave welding on the deflector a go. Looks like it will let some air out

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Make sure you open up behind the deflector well, but it will get extremely loud if you drill directly behind where the pipe now is. That will be a straight shot out the exhaust port. I’d rather enlarge the two existing holes as much as possible, and that will really cut down on noise.

 

[STOVE]

Make sure you open up behind the deflector well, but it will get extremely loud if you drill directly behind where the pipe now is. That will be a straight shot out the exhaust port. I’d rather enlarge the two existing holes as much as possible, and that will really cut down on noise.

I used the Herman layout for the holes in the face. I also have the stock deflector with th port opened slightly. Can try both. I’m sure I will get tired of the pipe one.

I may end up with a a second muffler as well to try different configurations

 

[sixonetonoffun]

Redneck in me has to ask...
Can't just use a zip tie on the ring?

 

[Shane¹]

Redneck in me has to ask...
Can't just use a zip tie on the ring?

I just used 2 popsicle sticks one on each side and pushed the rings in and slid the piston down in then put dirko on the 2 halfs after the piston was started

 

[singinwoodwackr]

Stihl waiting on my 1127 ring compressor tool, however a coworker gave welding on the deflector a go. Looks like it will let some air out

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Dat gonna LOUD, lol

 

[STOVE]

We have a chainsaw. A few things that were boogerbears in the assembly.

The ring compresssor tool works well.

The AV rubber grommet from the case to the main handle is much easier to put on with the chain brake removed.

The only thing left to do now is try to start it. I have both carb screws at 1 1/2 turns out. The other issue I’m having is the choke/kill spring keeps slipping under the lever when trying to put it on full choke. I may have bent it in disassembly or am just dense.

-did a very extensive muffler mod
- widen both intake and exhaust to 33mm
- Dukes pop up and Nikasil jug
- Dukes rim sprocket to 3/8
- Dukes mesh filter
- timing advance

 

[STOVE]

Cannot for the life of me figure out the contact spring. If I pull the trigger and push the lever to the full choke position it slips under everytime. Not sure if there is something broken off of the lever that keeps the contact spring, or if it’s bent out of shape and won’t work

 

[STOVE]

The contact spring was bent, had a big bow in it that was allowing the end to dip lower than it should.

Got the saw cranked. Will do some carb tuning tomorrow

 

[EFSM]

The contact spring was bent, had a big bow in it that was allowing the end to dip lower than it should.

Got the saw cranked. Will do some carb tuning tomorrow

The picture is dark enough I couldn’t figure out what was wrong. The contact spring design is something that Stihl surely is dedicated to, despite it being super stupid.

 

[STOVE]

Photo of the pipe deflector installed

 

[STOVE]

Finally getting the idle and low jet dialed in. Carb tuning is not my strong suit. Need to find some decent wood to get it in for a high jet tune

 

[STOVE]

This is the Initial run, idle was running wild and both screws around 2 out

Here is the tune as of this evening. What sounds should I be looking for to make sure I didn’t advance the timing too much

 

[Wood Doctor]

I have upgraded at least three Stihl 290 chain saws with 390 top ends. It takes some effort because the saw has to be practically dismantled with parts all over my workbench. Lots of work, but the owners have always been satisfied.