Comparing the 2 on the parts list show they both have the same crankshaft, so you're probably fine. Briggs also has spec sheets that they have which tell the different specs- which they have. Give them an ask. As far as replacing, it should be within your limits of mechanical expertise. I would remove the blade hub, drive pulley if it has one etc- inspect belt, blade etc to be ready to go when the engine shows. Remember to change the oil after break in to extend the engines life.

Thanks for the confirmation and info. I just removed the engine. However I could not get the pully or the a small block of metal (where the bland mounts) off the crank shaft. Any suggestions

Guess my question for above is what is the secret to getting the blade hub and crank pully off?

Whilst you have time on your hands- soak it w/ your favorite penetrant, or set the thing in a can of diesel fuel.(securely and in a safe environment) There may be a set screw in the pulley on a Snapper. Brush the shaft with a wire brush to remove what rust you can to allow the pulley to slide down easier. Or say skrew it and order new ones.

The basic engine should be interchangeable. Mounting bolts will be same, and since your new engine is 25mm x 3 5/32 shaft, pulley and hub will fit. The new engine may not have provisions for remote throttle or some other variation. Likewise, the cover plastic or sheet metal may be different or unique to Snapper. You can probably mix and match accessory components from the old motor and the new motor to make things work.

The hub and pulley often get rusted on pretty hard. Hub slides off and is clocked to the shaft with an internal, non-removeable key. The pulley uses a woodruff for position and is held by an Allen socket head screw.

If you can't get either off the old engine, new parts aren't than expensive. The hub is 7015626 and the pulley is 7015780. Both are $6 to $8 each.

Thank you Tomplum and Ggoyeneche,

You both provided me awesome information! I now have all the replacement parts to include:

6 hp engine (looks Identical to the old one),
new pulley, with key and set screw,
blade mount with spacer washer, and
Drive belt

I do have a few more questions if you don't mind.

I assume, I should install the new pulley and blade mount before I place the engine back into the mower chasey?

Will the pully slide up the shaft and into postion freely, or do I have take a measurement from the old engine pulley position and then set the new pulley in that same position?

Will the blade mount slide into position freely or do I need to give it some help with a mallet or hammer?

Thanks in advance

During instalation I noticed that the replacement engine does not have threaded mounts for the three bolts that secure the engine to the chasey....is this a show stopper or can I just purchase three smaller size bolts with nuts to secure the engine to the chasey... also it apperars the throatle linkage is the same but the other cable I think the dead swith does not match...can i rig this up some how?

Figured it all out...just had to think like a 20 yr old motor head that I used to be!

The bolts for the engine base are self threading... they performed correctly, The pulley and blade mount seated perfectly on the saft and finally after transfering the old blade brake linkage and rerouting some wiring to the blade brake the old snapper fired up... with vigor.

thanks for the help guys