2003 Honda 50 hp 4 stroke - burning smell - advice wanted

I have a 2002 Lund w '03 Honda 50 hp 4 stroke outboard - boat and motor are well cared for and run great - this season I have noticed a burning smell occasionally from the motor - it is not a bad smell and a friend recently said it was from a camp fire when we fished just off an island - then the smell came again and was definitely the motor - the smell does not last long - the water stream is good and constant and I can not figure what it may be - any opinions? thanks!

The smell occurs after the motor has been running a while.  The smell does not last long and may re-occur during a fishing outing and sometimes does not.  It is not a noxious smell like burning plastic etc.  There is no smoke evident either.

As suggested, I will check the battery terminals as well as look for any kind of oil leak.

Is this smell coming when you first start the boat?

Make sure your battery connections are all tight - NO wingnuts.