Outboard Motor life expectany

The PO on my boat had 2400 hours on his 1990 Johnsons before repower in 1996 with another pair of Johnsons. There's 800 hours on them now and besides a port motor that is hard to cold start when below 40 deg, they run fine.
 
We rebuilt a 1990 evinrude around about 2200hours, I think we got roughly 800-1000 hours after the rebuild before we noticed things were starting to break again and decided it was time to repower instead of rebuild again. It really depends on how well the engine was treated before the rebuild(maintenance and use) as well as how well the rebuild was done and how it was treated and used after. No engine will last the same amount but I would assume roughly 1000 hours. After that point we repowered with a 2000 200hp HPDI on our seafarer.