290-390 conversion questions

[STOVE]

A close friend of mine lost his father a while back. While clean g out the estate he found a ms-290 and was gracious enough to send it my way.

It’s clearly been sitting for a while from the photos. My guess is most hoses and lines will need to be replaced. While I am at it I figured I would go to the Dukes 390 kit.

From my searching on the site, a built In timing key can be filed to advance the saw. When I reassemble will it seat itself in the advanced position or do I need to do that myself?

Is the pop up piston worth the investment over a standard?

Bar looks a little long for a 290 but could be the photo angle

 

[PA Dan]

I did a 390 kit on a 310 a while back. On the flywheel after you file the key install and start the nut. You should be able to rotate the flywheel from stock to the advanced position. When advanced I tap the flywheel and tighten the nut.

 

[EFSM]

Honestly, I wouldn’t replace the OEM cylinder with aftermarket if it isn’t bad. Do a timing advance if it doesn’t kick back too hard and a healthy muffler modification—these mufflers are among the most restrictive ever on a saw.
When tightening the flywheel, start off by holding the flywheel by hand and turn it counterclockwise against the filed part of the key. Once you have the nut snug, torque it using your method of choice.

 

[2000ssm6]

Is the original 290 top end smoked?

 

[STOVE]

Is the original 290 top end smoked?

Not sure yet, haven’t gotten my hands on it.

 

[STOVE]

Honestly, I wouldn’t replace the OEM cylinder with aftermarket if it isn’t bad. Do a timing advance if it doesn’t kick back too hard and a healthy muffler modification—these mufflers are among the most restrictive ever on a saw.
When tightening the flywheel, start off by holding the flywheel by hand and turn it counterclockwise against the filed part of the key. Once you have the nut snug, torque it using your method of choice.

Am I filing the side of the key closer to the bar end of the saw correct? Turning the wheel further counterclockwise

 

[EFSM]

Am I filing the side of the key closer to the bar end of the saw correct? Turning the wheel further counterclockwise

If the key way is up, yes and yes.

 

[STOVE]

For all I know until I get my hands on the saw the piston on cylinder are good. But I want to do the conversion for fun.

Going with the Dukes kit. How do we feel about the provided wrist pin and clips? I have been happy with all my Dukes products so far but this will be my first top end.

Is the pop up piston worth the investment over the standard?

 

[huskihl]

Looking at the inside of the flywheel with the key on the bottom, file away the left side of it.

 

[huskihl]

Don’t use aftermarket c clips if they are shaped like a G and the loose leg makes a tight 90° corner. If they are c shaped or have a rounded end on them, they might be fine