flywheel key question?

turftech 1

turftech 1

Member
#1
#1
I have a 3HP Briggs flatttie. I had just cleaned the carb and cleaned and re-gapped the plug. So I fire it up, vroom vroom... sounds and runs 100% better. (It had sat for a long time, wouldn't run at all). It suddenly makes a nasty sound, one that I am pretty sure is the starter clutch binding, and it dies. Sure enough the starter coil is messed up, so I fix it, slap it back on, make sure the engine turns over nice. Go to fire it up, and the timing is obviously off. So, I pull the fly wheel, and sure enough the key is shredded.

Can the starter clutch binding really shred the flywheel key? Or did I do some internal damage? It seems fine, other than the flywheel key, and the starter spring was tweaked.

Thoughts?
 
Ratbike

Ratbike

Active Member
#2
#2
turftech 1 said:
I have a 3HP Briggs flatttie. I had just cleaned the carb and cleaned and re-gapped the plug. So I fire it up, vroom vroom... sounds and runs 100% better. (It had sat for a long time, wouldn't run at all). It suddenly makes a nasty sound, one that I am pretty sure is the starter clutch binding, and it dies. Sure enough the starter coil is messed up, so I fix it, slap it back on, make sure the engine turns over nice. Go to fire it up, and the timing is obviously off. So, I pull the fly wheel, and sure enough the key is shredded.

Can the starter clutch binding really shred the flywheel key? Or did I do some internal damage? It seems fine, other than the flywheel key, and the starter spring was tweaked.

Thoughts?
Click to expand...
Tighten down the nut on the crankshaft. When it comes loose it pushes out the starter and screams at you. Then because the flywheel is now loose the firing of the piston pounds the crank key into the flywheel and shreds the key. Get a new key and tighten that nut down very tight. You may need to stick a screwdriver in the fly wheel fins to hold it in place while tightening.Be careful not to break the fins on the flywheel though.
 
turftech 1

turftech 1

Member
#3
#3
Ratbike said:
Tighten down the nut on the crankshaft. When it comes loose it pushes out the starter and screams at you. Then because the flywheel is now loose the firing of the piston pounds the crank key into the flywheel and shreds the key. Get a new key and tighten that nut down very tight. You may need to stick a screwdriver in the fly wheel fins to hold it in place while tightening.Be careful not to break the fins on the flywheel though.
Click to expand...
I bet that is exactly what happened. Thanks.

I learned a trick from a friend of mine who is a Briggs mechanic. On the old flatties, when removing the starter clutch or flywheel nut, just pull the sparkplug and rotate the shaft so the piston is down, then lower some rope down the hole, just a few inches is enough, the rope will get squeezed between the piston and the head and won't let the crank turn. Unfortunately, I learned this trick after breaking a fin. I tried it a few times today while going through all my motors (I own a lawn care company, so I own about 15 small engines.) Anyway, it worked great.
 
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