how does oil injection work on yamaha 90hp

[litehook]

I have a 2004 90 hp,the #1 cly.loses oil from the clear tube going to the carb.The dealer said
this is normal that line is for mediun to fast rpms.After a couple of minutes oil is pumped to this line.It looks to me this is the olny oil the motor gets,or is there injection point somewere i cant see? thanks for any insight litehook

[boats.net]

The oil lines going from oil pump to intake manifold should never be out of oil. Put oil in gas tank, 50:1 premix until you are sure it's working properly. Check the inline one way check valves in oil line, it may allowing oil to leak past. If check valve is ok then replace oil pump and check valves.