Has anyone done this & did it work?
http://www.miata.net/garage/hsue/LoctiteCrank1.html

And does anyone know where to get the lower timming gear?  I have looked online at a few parts stores but can't find the gear.

Salvage yard, Hawks or this guy:

Parts Manager at

Mike Duman Suzuki
Suffolk, VA
757-539-1000

Tell him "Ack" sends you... 

I think I would fill in the worn area with aluminum epoxy if the pulley will keep it from falling into the oil pan.I would also be worried about where the metal went from the crank that is missing.

The oil seal is behind it, just a plastic dust cover over it.

The oil seal is behind it, just a plastic dust cover over it.

Yep, what mrfuelish sez...

This keyway is outside the engine block itself but behind the timing belt dustcover.  Any metal chips end up at the bottom of the dust cover.

 I read  the  fix you  have  hear  and  fixed my 87 samurai
 I used  JB weld to fix the  crank, keyway was wasted , so I picked up  used parts  at  a local pic a part  auto salvage for cheap!!
 lock tite  and have had no probs yet
Dwayne

If it's outside the block could you not weld the key in place? And how could something like that happen in the first place?

If it's outside the block could you not weld the key in place? And how could something like that happen in the first place?

Crank bolt come loose.  If you weld it in place, then you couldn't change the oil pump or seal.

I got it like, this cheep.  Body is in good shape, but it wouldn't run right.

I ordered the parts from Hawk & should have them Friday (I hope).

I had this problem with my tracker a few thousand miles ago.

What I ended up doing was welding a new key into the snout of the crank. The problem with that is that welding changes the temper characteristics of the crank, basically after welding it becomes soft mild steel and it loses its hardness. But then again the crank end shouldnt have wallowed out in the first place if it had been hardened properly.     

The end result was that it lasted about 1500 miles, and then the problem returned, and was worse than ever before. Eventually it got to bad to fix again. I have talked to some other guys on other forums that have used the Locktite fix with the same result I got from welding the crank.

The only correct way to fix that problem is really replacing the crankshaft.

What I did was found another wrecked truck for $200, and just lifted the running motor from it.

Another possibility would be to have a machine shop cut another keyway 180 degrees from the original. and run the timing gear 180 from the timing mark.