[9989]

I just installed a used 1989 yamaha 225 excel motor on my boat. I've noticed that about half of the oil in the main tank on engine drains back to the remote tank when the engine is in the tilt position. The tank refills when i put engine down and turn on key but this seems strange. Is this normal operation? Everything else seems fine. I would appreciate any advice.

[rodbolt]

its common. if it bothers you use a fuel line check valve from later yamahas and install in the oil tank line. never seen it hurt anything though. the 225 merc offshores did the same thing only then you would have to go bleed the engine tank to allow it to refill.