044 Stihl not running well

I've posted in few other posts that my 044 was not running well. It was running but wouldn't idle well. I would tune and run a bit then need to retune. This Spring I decided to rebuild the carb, change filters, and inspect cylinder. All went well and looked good.

Saw starts and runs but won't idle unless brake is on. Have to keep on trigger goosing it to idle. It would over rev when on the trigger.

Several suggested pressure/ vac testing. Which I agree with. The compression hasn't been measured but the saw will try to pull a shoulder out whenswhen starting soIso think its good.

Started unbolting everything to setup for a pressure/vacuum leak test and found this.

The oiler is covered in old dirty crud that was pooling fuel. When I got the oiler removed I found part of a seal....
I'm guessing that's the leak. The old crud was making a partial seal. Still need to verify it and check for other leaks.

Does one change this seal like I've seen on YouTube? Make seal puller and just gently tap/press in the new one flush? I'm probably change fuel and air lines while I'm in it. It's never had any replaced since new.

 

There’s a sleeve that pulls off. Between the threaded part of the crank and the bearing. Then it’ll be easier to get something in there to pry the seal out.
Set the new seal deep enough so that the outer seal lip is just up onto the larger part of the sleeve. Too deep and the seal will wear on the bearing. Not deep enough and it will ride on the oiler worm gear

 

Wiggle that crankshaft and look closely at the bearing once you have the seal out.

 

Plan on checking the bearing. It feels really good as the saw sits right now.