Hi all!

I have an ancient John Deere riding mower. It's got a car battery on it. Aside from having inner tubes installed, it's done really for us since we bought it a couple years ago,

Last week, we got it stuck in the mud. Our neighbour dragged it out. But it appears that in our attempts to get it out on our own, we broke something.

When I try to turn it on in choke, I can hear the motor doing something ("rum-rum-rum-rum-rum"), but it never engages or starts fully when I put the throttle leaver (I don't know the actual words for the parts, sorry) down to Fast/Slow.

I was going to hire someone to fix it but yesterday we fixed our old gas push mower by finding the spark plug on the ground and putting it back in, so I feel like I'm a roll here.

Any ideas where to begin for troubleshooting? DH wants to try charging the battery but if the engine does SOMETHING when I turn the key, wouldn't that mean the battery is working? HALP.