I have a Bolens H16 with a 18618 tiller. I've used the tiller a couple of seasons and it works well, though the tractor engine seems a little tired when I work it hard. As I was hooking it up this year, it occurred to me that it might be a good idea to check the oil level in the gear box. It's very low, but I have no idea where it should be or whet to add. Any suggestions? I found a parts diagram, but no owners manual in the manual section of the site. I'm new to this site, looks like a nice resource. Any info about lubricating my tiller would be much appreciated.