Flywheel pulling?

[Bill G]

Choices..............

 

[LAWN BOY]

Choices..............

View attachment 451404

I seen that the other day lol

 

[Coupe]

The steering wheel puller I got came in a plastic carry type box with 3 lots of
3 bolts to fit into the holes of most of your chainsaw or any flywheel to pull
with.THE Bolts that are supplied in the kit are metric but I go to my closest engineering
shop if the threads are imperial and get what ever thread I need. If to long
I just cut them to length and you are in business. Most chainsaw flywheels are a pain as
nine times out of ten you cannot get the legs of the puller underneath the flywheel.
I found that for I think off hand a $18 steering wheel puller has saved my butt
hundreds of times.

 

[heimannm]

If you add consistent light pressure from underneath with a pry bar or screw driver, a solid whack with a brass hammer almost always works. You can leave the nut on the threads to protect them, but if you’re a bad swing the nut can wreck the threads too. Any side loading that does occur can be easily relieved with a few taps on the clutch side.

LIGHT pressure! BRASS hammer!

A few weeks ago someone left a very rough McCulloch PM650 here. I have an intern (local high school) so I had him work on it for the experience. We checked compression and it was 155 so I decided it was worth the time & effort to make it a runner again. Tore the saw down, removed the flywheel using the "smack the nut while holding the flywheel method" and proceeded to tear the saw down for a good cleaning.

After cleaning I tried spinning the saw over and it would only go part of a revolution...so I had him break the crankcase open (clamshell design). We could see nothing wrong, no foreign objects in the crankcase or cylinder...so reassemble the saw with a new PTO side bearing two new seals. Upon reassembly and torquing the screws we were back to a dragging resistance and I thought the flywheel looked awfully close to the crankcase. I used a hard plastic hammer to "realign" the crankshaft and the saw turned freely.

At that point I just assumed the intern had dropped it while cleaning and caused the crankshaft to shift, but when I was installing the flywheel nut I remembered our disassembly process and knew what had happened.

I will still use the "smack the nut" method for many saws, but will try to be more aware that it is possible to shift the crankshaft on the bearings when you use that procedure.

Mark

 

[Ketchup]

A few weeks ago someone left a very rough McCulloch PM650 here. I have an intern (local high school) so I had him work on it for the experience. We checked compression and it was 155 so I decided it was worth the time & effort to make it a runner again. Tore the saw down, removed the flywheel using the "smack the nut while holding the flywheel method" and proceeded to tear the saw down for a good cleaning.

After cleaning I tried spinning the saw over and it would only go part of a revolution...so I had him break the crankcase open (clamshell design). We could see nothing wrong, no foreign objects in the crankcase or cylinder...so reassemble the saw with a new PTO side bearing two new seals. Upon reassembly and torquing the screws we were back to a dragging resistance and I thought the flywheel looked awfully close to the crankcase. I used a hard plastic hammer to "realign" the crankshaft and the saw turned freely.

At that point I just assumed the intern had dropped it while cleaning and caused the crankshaft to shift, but when I was installing the flywheel nut I remembered our disassembly process and knew what had happened.

I will still use the "smack the nut" method for many saws, but will try to be more aware that it is possible to shift the crankshaft on the bearings when you use that procedure.

Mark

That’s a really good example. It seems a lot more prevalent on certain models too. The obvious ones like that don’t worry me too much. It’s the ones that stay slightly off center for significant run time. Bad for rod bearings as well as the crank bearings. I haven’t had a lot of premature bearing failures (none that I can remember) but I could see it being a problem. Especially converting something like a 2100 or 9000 to race applications or hard use or increasing compression a lot.

I’ve had luck putting the clutch side into a hole drilled into a board on the bench before whacking. It wears out the board but seems to limit the travel of the crank. I also find there’s a frequency to the whacks that breaks them loose. Maybe others have noticed that?