Sheared flywheel key?

I've never had to mess with removing the flywheel nor fixing a sheared key, but I think that is what I am looking at.

The backstory : I bought a toasted 038 Super and converted it to a Magnum. Rebuilt top end up with OEM Mag used jug and a new meteor piston(I think) and rings plus all new filters, gaskets and such as well as fuel lines and carb rebuild. Saw runs good. I deleted the base gasket and my compression tester sucks but its got plenty of compression says my puny arms. Can't remember squish or if I even measured it properly.

8 tanks or so of runtime later, plus a sweet deal on a 441C-M and its time to sell. My BIL decides he wants a bigger and better saw than his Poulan so I sold it to him. 2 days later I get a text that it was running great but...

Tl; dr fast forward here:

Saw is hard to pull but will. It jerks the cord back viciously. I can get it to run but something ain't right. Looked to be smoking from exhaust and easy to stall out. For fear of damaging things more I didn't continue running it. All signs point to timing? I haven't pulled the muffler yet or done much of anything. 12 hour work day, I hate it when my real job cuts into my tinkering time.

Steps to take before removing flywheel? Any other advice before diving in?

Thanks

 

Go on and remove flywheel...
Report back..
If he pulls it over and there's no slippage, it may not be your problem...

 

Im curious.

 

Had you removed the flywheel during your initial rebuild? IIRC some of the older Stihls' had flywheels with two keyways in the flywheel marked A&B, make sure that when you remove the FW you check for 2 keyways and note (by marking it with a Sharpie) which one is engaged with the key. Using the wrong keyway will give you all manner of timing head aches!

 

I did not touch this flywheel... Nor have I ever on any saw so I am here for some hand holding. Got to put the wee ones to bed soon and clean up the joint then I will start digging in.

 

Can't wait

 

I need to grab a piece of stock from work as the nut and crank are too deep to get at.

 

have you pulled the muffler yet? I ask because I loaned my brother's wife a little MS210 and when I got it back it was hard to pull...never had this problem before. Didn't mess with it at the time, a month later I pulled the muffler and it was completely full of gas and cylinder was full of gas. She had it flooded so bad that it couldn't compress all the liquid in there.

 

I haven't but will as its a simpler, and less prone to error task. I did pull the plug and tip the saw over and repeatedly pull, expecting a flooded saw but nothing came out. Then again, if its in the crank or muffler that wouldn't have helped.

Stock in hand, hopefully get to tinker this evening.

 

Stuff some cord in the cylinder to hold the engine from turning over and take off the flywheel nut. I believe you should be able to see if key is sheared without pulling flywheel off.

 

I did, that nut was backed off already and flush with crank end in the pic. My hammer was too big so that's what stopped me from popping it off.

That's the thing I don't really know what I'm looking for... how can I tell? Where should the key be? I see a little slot with nothing in it...

Sorry, definitely rookie questions. I like to learn this stuff and figure it will come in handy in the future. I'm a hacker/ enthusiast!

 

Let me look and see what I have in the shop to take a pic

 

First pic shows key if you look down keyway. Second shows keyway with no light shining. You can't see in very well.

 

Got it rookie1, thank you sir!

 

I don't think you could accurately detect a shear without taking the flywheel off because you can only see they keyway on the flywheel and not the crank...impossible to tell if they are aligned if the key is still in the flywheel keyway.

 

Understood, I think rookie1 was just suggesting it may be very obvious before even pulling. Yes the inner bore is threaded, set up for that standard Stihl puller deal. I've got a generic puller coming from work if I can't free it up like Mitch shows in the YouTube vid... He makes stuff look too easy sometimes, internet courage.

 

Whack a mole not working, so I am going to wait on the puller.

 

Hammer, whack-a-mole! I'm going to get myself one of these, MM's posted the way to do it right. I use a "customized" double arm puller now but its still tough sometimes if the cylinder is still on, fins get in the way. (Customized = ground down to make it fit in there!)

http://www.ebay.com/itm/380899237446?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649