Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

   My chipper stopped working.  It is not mulching leaves or creating an output wind.  I think it has a broken key.  From the drawing it looks like the only culprit.  How do I install a new key?  It seems like I’d have to take off the big cover opposite the motor then the flail section.  The key probably slides into the flail hub.  If that right?

Hard to see where the key/shear pin is on the diagram. In most small engine applications I've seen, the shear pin is usually on the crank. However, in many modern day applications, (motorcycles), tapered shafts are used without any key at all. I changed the electrics on a couple old Yamahas and the new system didn't use a key between the crankshaft and rotor. I found this strange because the rotor is a precision mounted piece that controls engine spark. I've run those engines up to 10,000 rpm and have had no issues with the rotor slipping.

Hey Trouts,

I have a pdf breakdown on your Chipper/shredder..(the briggs 5 hp model) send me your email and I will send I to you..

The break down is very easy to see, compared to what you posted on the forum...


Friiy@aol.com

Borat - The key is #3 on the drawind just to the left of the engine.  I'm not sure it holds the flail in place.  I'm guessing it does.

Friiy - I have the 5hp manua for the 247.799891.  The body matches my machine.  I don't have a way to snip a page out of a pdf so used the louzy drawing. 

OK. I see the key now that you've pointed it out. The diagram isn't too easy to read.

Hey Trouts,

25% chance the crankshaft is broken.... The keys don't shear very often,  without a belt to slip the momentum of the chipper stopping suddenly they can snap the crank....

Friiy