I just grabbed a 10hp 4 stroke and the label says it is a "B100L-1500444" Everything I see for parts says lists a BF100, and only gives one serial number like 15000-. I am thinking the serial number being 1500444 means it is a 1983 engine, is that correct? There for I can order anything in the 1500000 range and it will be for that year engine?
It really is confusing when you look at the sites for parts and the numbers on the sites don't match the numbers on your engine. It appears they stuck a few extra characters in there.
I need a thermostat, water pump/impeller, and the top seal for the crank. I have not torn it apart yet as I would rather get the parts then tear it apart and put it back together the same day, as opposed to tearing it apart and waiting 2 weeks to put it back together, my brain tends to miss important details and I have to do it twice.
Thank you for any help.

New forum member, Kevin

Your are mostly right. It is a 1983. Your model number is BF100D LA. It is long shaft motor, so you have to be careful to be sure that certain parts in the lower part of the motor are correct, since it is a long shaft and not a short shaft.

Here is the link to the parts Honda Outboard Parts Pre-1997 BF100D LA OUTBOARD ENGINE, JPN, VIN# B100L-1500001

Mike

Mike, thank you that is the info I was looking for. I think I would have ordered the right stuff, but was nice to get the re-assurance. Now to order and install the water pump, top oil seal, thermostat, and who knows what is next. The wonderful part of $100, Craigslist purchases.