Heavily corroding Power Trim and Tilt Motor

[Icom]

Guys my power trim and tilt motor is heavily corroding.  What would you suggest i could do to slow down as much as possible the corrosion? The engine is a Yamaha 50HP 4-stroke.

[skip]

Check all grounding wires on the bracket/lower unit/power trim and tilt.

Could be one is cut/corroded. Look up the parts schema online to see where they should be on your engine.

Check for current leakage from a bad ground on your boat / wiring issue.

Are your anodes all in place? Stainless prop or aluminium. Which antifouling did you use on the engine?

[Icom]

Hi Skip, thanks for the fast reply.  Unfortunately i dont have a clue about grounding wires and how they operate on an outboard.  The engine was bought recently as second hand and only had 126 hrs.  I noticed the motor cover had rust on it.  The guy who installed the engine for me put on some sort of clear spray on it.  Apperently this is quite a common problem on the motor covers.  I was thinking of applying some marine grade grease over it until i pull the boat up for winter (December) and when laid up i carefully remove the cover and take it for sandblasting and spray galvanizing.  Do you think this would solve the problem?  The anodes have just been replaced 3 months ago.  Previously, the owner, put fresh paint over the lower part of the bracket and negligently painted over the anodes too making them ineffective completely.  I brushed down the area where the anodes touch the bracket and replaced them with new ones!

[baghira]

I sprayed my gearbox 2 times...
The last time I used only best products, acid etch, primer jotun HB, paint jotun.... still I can see some corrosion at some points....

[aidanxuereb]

This is very strange...i have a Yamaha 115hp 2 stroke which is 15 years old, and is as good as new. And it spends 4 to 5 months constantly in the sea. Something must be definitely wrong with yours Icom.

[baghira]

Went to buy that spray (anti corrosion) to see if it helps....
Too expensive 22euro for a can of aerosol. Ended not buying it.
Will use waxoil like I did... I works best if there is no corrosion at all not after... hence neither will work well

[Icom]

This is very strange...i have a Yamaha 115hp 2 stroke which is 15 years old, and is as good as new. And it spends 4 to 5 months constantly in the sea. Something must be definitely wrong with yours Icom.

@ aidanxuereb its actually very common on yamahas that the the tilt motor cover rusts away like crazy.  Do a google search and you will find out how common the problem is.  Many in the US when replacing their tilt motors, they buy after market cause Yamaha tilt motors apart from being very expensive are know to use inferior metal for the motor cover.  In your case you probably have a particular model which didnt have this problem.