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From the looks of this. Seems the flywheel key tried to come out the top. In doing so, broke part of it, and bent the rest of it. Also broke a big chunk of the fly wheel cone.
There's still a good piece of the key that I used to see of the keyway had spread any. And it did.
Example: when you sick a good fly wheel key into a keyway, there's very little wiggle room. Stick it in the top of the crank now, and there's about double the wiggle.
Thus on a customers, and I'm scared of putting another key in it, with it as loose as it is.
Looking for advise. Is the crank junk? Can I put some foil in it to tighten it up?

The engine must have a steel key which I think was a very bad idea for the very problem you outline. The soft key B&S used for ever until recently would not have damaged either. The several 33 series engines I have had did have a soft key but I hear they are recommending hard keys now. The engine has apparently been run for a long time with a loose flywheel. The original idea of the key was to hold the flywheel and crankshaft in position until the nut or bolt was properly torqued. When the flywheel is properly torqued the tapper holds the two in place. IF the keyways of both the flywheel and crankshaft are damaged the full length to where there is no longer enough to properly align them using a longer key, I would get a larger key and try to file it to a snug enough fit to hold the two properly aligned then make sure to use a torque wrench and perhaps add 10% to the recommended torque. IF that fails, then a replacement engine may be in order unless you have access to a replacement flywheel and crankshaft. Think of your labor involved. You may want to let the customer make the decision given the options.

Walt Conner























There is now way a key can try to come out the top and damage the keyway all the way down. n try to come out the top

The use of a steel is a possible. As there is a couple APSI on these 330000 series engines as Briggs had to redesign the flywheel and crankshafts.

APSI 82

APSI 89

Here's a few pic of the damage.

looks like there might be enough key to locate the flywheel
Now here is the go.
Get some diamond grinding paste around 10 microns
get some cotton wool , NOTHING ELSE WILL DO . (YES I AM SHOUTING ) and pack it hard around the crankshaft below the level of the oil seal
Now use the paste to lap the flywheel into the crankshaft.
Allow about 2 hours for this it is slow
When both the crankshaft & flywheel tapers have a uniform dull look all over they are lapped ( same as a valve seat but valve paste is way too coarse. )
Clean the crankshaft thoroughly before removing the cotton wool
IF you allow any of the paste to get into the engine it will pass right through the oil filter and destroy the big end in a very short time.
When done properly a taper wet with water will seal so tight you can just about lift the engine by the flywheel without the bolt being in place.
when you replace the flywheel align the keyway very carefully.
Put a jack under the pulley if the motor is in the frame or stand it up on the PTO shaft
Give the flywheel a hard "tap" with a dead blow hammer , a lead one is the best to use .
IF you don't have a lead one then make one, hundreds of videos on how to make one from an old battery .
A leather faced one is also fine but steel hammer or copper are too bouncy as is a rubber or plastic faced mallet .
Then torque up the bolt and hope you never have to remove that flywheel again.

Can't tell if that was the new style flywheel and crankshaft as that key was the new 591757 steel key. To me it looks the old style crankshaft.

Either someone put in the wrong key, under torqued, or over torqued the flywheel.

Well perhaps lapping won't cut the mustard with that flywheel

bertsmobile1 said:

Well perhaps lapping won't cut the mustard with that flywheel

Click to expand...

There's no way I'm good enough to do all that you described. I appreciate the info. Even with another flywheel I have to fit it. And not sure if I could even find that paste, due to the fact that power is out in the next 2 to three adjacent towns. Wide spread outages right now.

According the APSI 89 that engine should the newer crankshaft and flywheel. When ordering replacement make you order the right parts per date code break.

And it sounds you are getting a dose of what went thru Sunday night there. Hopes things are only power outages.

Suggest you replace the engine with a good used 31 series which will be a direct replacement and more plentiful than the 33 series. Alternators will interchange IF there is a difference there, IF you do that and have to change the alternator, the 31 will likely have a soft key IF not, throw the steel key away and put in a soft key and use torque wrench.
Walt Conner

PTmowerMech said:

From the looks of this. Seems the flywheel key tried to come out the top. In doing so, broke part of it, and bent the rest of it. Also broke a big chunk of the fly wheel cone.
There's still a good piece of the key that I used to see of the keyway had spread any. And it did.
Example: when you sick a good fly wheel key into a keyway, there's very little wiggle room. Stick it in the top of the crank now, and there's about double the wiggle.
Thus on a customers, and I'm scared of putting another key in it, with it as loose as it is.
Looking for advise. Is the crank junk? Can I put some foil in it to tighten it up?

Click to expand...

Been There done this: align crank and flywheel. drill through or most way through I think I used 3/16 install roll pin. It won't break again. Yes it works and beats replacing crankshaft. Use a good drill bit. don't break it off in hole unless all the way through and don't have a roll pin.

I wished I had thought of that before I tried my repair. I stuffed the key, at the wallered out part of the crank with foil. Trimmed off the edges with a razor. Nice and easy,set the (brand used) flywheel down onto it, and torqued it down.
Told the customer I'd warranty it for 30 days.
If it comes back, I'll put the roll pin in.

BTW, if it does come back, should I consider putting some loctite in the hole when I insert the roll pin? Or will the roll pin be fine without?

PTmowerMech said:

I wished I had thought of that before I tried my repair. I stuffed the key, at the wallered out part of the crank with foil. Trimmed off the edges with a razor. Nice and easy,set the (brand used) flywheel down onto it, and torqued it down.
Told the customer I'd warranty it for 30 days.
If it comes back, I'll put the roll pin in.

BTW, if it does come back, should I consider putting some loctite in the hole when I insert the roll pin? Or will the roll pin be fine without?

Click to expand...

Loctite can't hurt, depends on roll pin fit and if you need to remove flywheel ever again. heat will loosen loctite but burn up magneto.

Boy, is that ever a shade tree repair. IF you are doing that for a customer, forget it. (Maybe use some bailing wire on it)

Walt Conner

Tinkerer200 said:

Boy, is that ever a shade tree repair. IF you are doing that for a customer, forget it. (Maybe use some bailing wire on it)

Walt Conner

Click to expand...

I agree. Wished I'd have used the roll pin.

Well it was the roll pin I was talking about!
Walt Conner

Tinkerer200 said:

Well it was the roll pin I was talking about!
Walt Conner

Click to expand...

Hi Walt, It gets worse.. I didn't even drill all the way, just through half flywheel and crank, didn't want to chance breaking the bit. I was surprised how easy it was to drill through the crank. It was not hard at all. No way to get that pin out now without drilling again!. Did what I had to do when faced with a trashed crank and flywheel. Not a customers, I inherited the nightmare. Works like a champ.