Hydraulic trim hose block disintegrates

[surfer23505]

Have a mercruiser inboard/outboard with a pre alpha drive. There is a block on the underside of the outdrive that has two hydralic lines coming in from the pump and then 4 on the outside leading to the trim cylinders. Well on the inside where the two lines from the pump come it it always starts to disintegrate and the hydraulic lines will fall out when the threads are all gone. All my zincs are good and it always happens on the inside lines as well. Any thoughts would be greatly appreciated. Also it is not something that happens over a long period of time but rather will happen in a matter of months.

 

[Bt Doctur]

Re: Hydraulic trim hose block disintegrates

electrolsys?? transom not bonded correctly to inner plate and engine.