Immediately after posting this I discovered that my engine is actually a 31C707-33460G5. I thought the C was a 0 didn't even consider it might be a C .
Sorry about that.
I'm trying to find a manual for a Briggs & Stratton 17.5 motor. 310707-3346-G5. That type doesn't show up in B&S's website. It came on an Ariens mower and their site doesn't have any information about the engine either.