Aside from the infamous crank failure stories that you hear, what you have there is a very reliable sled. I would highly doubt any noise you are hearing would be a crank failure about to happen. There's a lot of weird noises that you will hear comming from under that hood. If it has a Team roller secondary clutch, they make a lot of noise. If it's a sound that is progressing you might have wear in your primary clutch, ie. rollers going bad, weight bushing going, etc. If you don't know the maintenance history of the clutches I would recommend pulling the primary and sending it to SLP for a cleaning / rebuild / balance. It makes a big difference in clutch life and a BIG difference in crank life since an out of balance clutch can kill a crank.
I have an '02 edge and last year my crank broke right behind the PTO bearing. I sent the crank with a new PTO crank cheek to Precision Performance Products in Idaho Falls. I had them do a crank rebuild, weld, and a big (double wide) bearing upgrade. The most expensive part was the crank cheek (around $250). If you take an existing crank such as yours, send it and the case halves they can check your crank for true, install the big bearing and do the case mod (very minor) you will buy yourself a lot of peice of mind. My sled engine has never run smoother. Actually I just had them do a 700 of mine this fall.
The only bad thing about all this is that the snow is falling and it's to bad you didn't address this a couple months ago. The good thing is that both the shops I speak of generally have very short lead times on turning your parts around. They both have performed all of the above in 2 days for me.
If you have never rebuilt these motors make sure you have someone with experience help with the re-assembly. These motors are a little sensitive to torque specs, type of crank sealant, etc. I've done plenty and have learned some lessons.
.....whew! Hope this helps.
Ken
