STIHL 041av flywheel trouble

[Pioneer620_88]

I have a 041 that I just recently took the flywheel off of to inspect the coil...now that I'm putting the flywheel back on It will spin freely by hand, but as soon as I tighten the flywheel nut it will jam up and I can't spin the flywheel at all. Is there something that I did wrong?? Any help would be appreciated

 

[northmanlogging]

should be a woodruff key that locates the flywheel to the crank... its itty bitty 1/4 moon looking thing... pretty important part to loose too

Should be able to get a replacement at any servicing dealer

 

[Pioneer620_88]

The woodruff key is there...so why would it cause the flywheel to jam up?...actually it sheared off after so now I need a new one anyways...but if the key was in the slot, how would it keep the flywheel from moving with the nut tightened down?

 

[northmanlogging]

The woodruff key is there...so why would it cause the flywheel to jam up?...actually it sheared off after so now I need a new one anyways...but if the key was in the slot, how would it keep the flywheel from moving with the nut tightened down?

??? so when you tighten the fly wheel nut the entire mechanism crank and all does not spin?

if you sheered the woodruff key, I'm gonna guess and say it wasn't located properly, they can and will slip out when reinstaling the flywheel, and can then get jammed against the crank seal or some other part of the saw case

 

[Pioneer620_88]

??? so when you tighten the fly wheel nut the entire mechanism crank and all does not spin?

if you sheered the woodruff key, I'm gonna guess and say it wasn't located properly, they can and will slip out when reinstaling the flywheel, and can then get jammed against the crank seal or some other part of the saw case

You are correct, when I'd tighten down the flywheel nut the crank would not spin at all...but every time id take it apart again the woodruff key would still be in the slot so it didn't slip out at all...I just lost my patience with it and put it all back together and tried to pull it over and ended up shearing the key.

 

[northmanlogging]

You are correct, when I'd tighten down the flywheel nut the crank would not spin at all...but every time id take it apart again the woodruff key would still be in the slot so it didn't slip out at all...I just lost my patience with it and put it all back together and tried to pull it over and ended up shearing the key.

did you use something to stop crank rotation when loosening/tightening the flywheel nut? Usually there is a plastic doodad that goes in the spark plug hole, but I've seen (it was me...) use a screw driver through the exhaust port and that messed up the cylinder walls

Other wise I'm stumped, unless the clutch side was messed with and something got jammed in there too?

 

[Pioneer620_88]

No I just gave the nut a couple quick shots with the impact drill and It came loose pretty easily. So nothing's jammed in the cylinder..I just ordered a new flywheel key today so I Guess I have to wait for that to come in to try again.

 

[northmanlogging]

guess the other thing could be jamming against the coil?

 

[Smallenginetime]

I know I'm late to this party and this is my first post but I'm trying to revive an old 041 Farmboss from my father in law and my flywheel is doing the same thing as the OP, if I tighten it to spec (29NM) it's locked against the case.

I can put some torque to it, maybe 10NM, before it is bound up against the inner case but that's it.

Anyone dealt with this before and found a way out?

Thanks!

 

[Bob95065]

I'm sorry for digging up an old post but I'm having the same problem. How did you guys resolve this?

 

[HarleyT]

I'm sorry for digging up an old post but I'm having the same problem. How dud you guys resolve this?

You need to give your details first. The flywheel should be locked onto the crankshaft, it is held by the torque of the nut and the taper of the mating surfaces, the key just holds things in the correct position while you torque down the nut.

 

[Bob95065]

What I did is I had the key in the shaft and I had the flywheel loosely on the shaft (no nut) when I set the timing. Once the timing was set I torqued the nut and the cranksghaft was very difficult to turn but I was able to do it a little. I remobved the nut and pulled the flywheel off to find that the ridge was now shiny from the flywheel making contact and me turning it.

 

[Bob95065]

I posted in another forum and a member there said the Service Manual listed the correct flywheel. I found this in the manual:



The SM lists 0204003033 as the flywheel. This is a photo of the part # on my flywheel:



I am building a 041 Super. Does anyone know if the Super took a different flywheel than the 041? This build is from a box of parts from different saws I picked up. There is a 041 cylinder in there so there must have been one in the max at some point before the PO gave me the parts.

 

[Bob95065]

I solved the problem. It may be a redneck solution but it worked.

I looked at where the interference was and I came up with a way to relieve it. I used my stationary belt sander to bring the end of the flywheel down a bit to make clearance with the case. It didn't take much and I was able to torque the flywheel nut down. I checked for spark right away and it worked. I completed assembling the saw and it started right up and ran well.

You guys may be right that the Supers had electronic ignitions, at least this one may have. The top cover says "Electronic". I may have the only one with points ignition. The box of parts only had that ignition with a brand new set of points. It may have gone with the other saw, who knows.

I put a scrappy bar on it to set the carburetor. It may be ugly but it was a fun project.