motor too high and out of adjustment holes

[Willyclay]

water hits the cav plate and spashes back in to the boat..

I have a bud with a 15BW & 70 Yammy that experienced the same problem BUT the water was being splashed by his depthfinder's transducer mounted on the transom. You appear to have something like that on your transom. You might want to double-check the source of the spray before adjusting the engine height. FYI, my bud made a splash deflector from a piece of four inch PVC that he bonded to the hull with 3M 5200. Works great! I'll try to get a picture if you are interested.

 

[fhhuber]

Yamaha 90 mod#6h1L1008548

These pics look like the whole prop is below the keel so lowering the motor is probably mot going to help anything.

Might be trimming it wrong, if that is as far down/forward as you are getting the motor it could be still pointed in a manner that will either lift the bow or throw water up when applying power from a standstill. I'd try going to the next hole on the trim peg if its manual trim or use the power ,trim if equipped, to push the top of the motor back and prop forward.