Great to hear.
I had an old 62 tooth gear that was in pretty decent shape I replaced but had just threw it out. There is usually more wrong than the big gear as you investigate. The bearings (bushings actually) as well as the hubs and other transmission stuff. It can get quite expensive as you replace. A donor machine is a great option. Make 1 good one out of 2.
Keep us informed.
Matt
So I bought the mower, rolls well, I'm going to replace the blades. But that is a separate issue. Anyway, I used the engine off my SRM140 which is a Briggs 286707 and it replaced the Briggs (I think) 28T707. trouble is that during this changeover process, I figured out the wiring is a smidge bit different. It seems to be it's not getting any spark due to some wiring issue. I'm half tempted to just use all the wiring from my SRM140 to the new mower, but I'm sure there is a simple way of fixing this. The mower I bought is a SR1028.. Thanks to all in advise.!
Yes, so without looking at model numbers, just think about what the circuit is. A Briggs should get spark if no wires are connected and the magneto ground wire is not touching anything. So the magneto wire is the "kill switch". Grounding that will stop the engine.
If you have a simple continuity tester (HF cheapy would work) and test any, all the switches to make sure they still work. Can you also provide a simple basic drawn on paper diagram of wiring and colors perhaps. Here is a link to mine which adds complexity in the key switch start mode but you get the general idea even though its a Honda. Same principle idea
http://www.lawnmowerforum.com/attachments/snapper-forum/31689d1492775292-snapper-rer-28085s-restore-electricaldiagramsimple1-jpg
Thanks for the neat wiring diagram! That needs to be put on a sticky somewhere on this site as there has been several members in the past requesting that info.