Small Engines (Lawn Mowers, etc.): B&S Engine swap on rear tine tiller, rear tine tiller, rear pulley

Question
I have a Craftsman 205cc rear tine tiller, Model No. 247.29931 and the engine is a B&S 205cc model no. 12T102-0751-F8 currently mounted stock. The engine is frozen and I need to replace it. I called local dealer that said the exact replacement is 500 bucks. He said there is another replacement engine but the shaft is 1/8" longer, and 200 bucks cheaper. He said that is the only difference. Before making the purchase I wanted to know if this 1/8" difference is going to be an issue when swapping, and if you have any pointers on swapping the motor as I have never done anything like this. The tiller is actually my dads, and I can't return it until I fix it. The repair shop said it would take them about an hour of labor to swap the engines but they would have to charge me another $100+ bucks on top of the engine cost. Basically need to know if the differnce in the shaft is concern and basic steps to easily swap engines.

Answer
Looking at the parts diagram the 1/8' longer shaft may make a big difference as the rear drive pulley is bolted to the end of the shaft.

You can always remove the old engines crankshaft, inspect for damage, and see if it is still usable.  If it is still usable you can buy the cheaper engine and then swap out the crankshaft.  this is a challenging job for homeowners and it would cost too much for the shop to do it.

If you buy the engine you may need a puller to remove the engine pulley.  An option may be to remove the engines 4 bolts, remove the engine and see if the rear pulley comes off easy.  If you can not get the pulley off the shaft you can always take to a shop and have them remove the pulley and install on the new engine.

My advice would be to buy the correct engine...you will be thankful later.

Eric