water in tilt/trim reservoir

I have an 88 MErcruiser 4.3LX with the Alpha One outdrive. I have the later model tilt and trim pump oildyne/eaton, i believe. My boat was left with the plug in, of which water got into it when it rained. I have water in my tilt/trim system, and am wondering the best way to bleed/flush the reservoir and system to get rid of all water. Of course, I did not notice the water in the sytem until I trimmed the system down and up, only to notice that a milky white substance was coming out of my yellow cap. Any input is greatly appreciated. Thank you boat gods for your help!

Re: water in tilt/trim reservoir

I don't work on I/O trim but I do know that water will rust out ram pistons and ball bearings and lead to the ruination of any system. So you need to get it out yesterday. Hydraulic oil (as in bucket trucks and industrial automation) is engineered to have some water absorbtion and may be your best choice for refill. On an outboard I would take the hoses loose and manually lift the prop up/down. All the water and oil would squirt out into a bucket. I would take pump apart and wipe dry wioth shop towels. I would blow air through hoses. Then put back together and run a couple of flush & fills with mineral spirits. Then another drain and a final fill with good hydraulic oil. Not perfect, but good enough to keep the rust bug away.

Re: water in tilt/trim reservoir

My boat had the same problem. I don't know where your pump is located, but you had better also check engine oil. You cannot judge the condition of the engine oil by looking at the dipstick!! Depending how high the water got, you might have water in the drive bellows and posibly in the gimble bearing.
Just my .02 based upon the experiance I had with our boat!

Re: water in tilt/trim reservoir

Maybe you must check the power trim pistons. I think that they need service. When the boat is in the water have you checked if there is an oil leakage in the water? And something else, when the drive is at the up position (not full up necessarily), if you try to push it down with hands, can you move it down? If yes,then you must service your power trim pistons for sure, and that is why you see water in you reservoir.

Re: water in tilt/trim reservoir

This is a GREAT forum. I was about to ask the same question because I noticed that the reservoir fluid is milky (like strawberry flavored, rather than chocolate, milk. I will get the cylinders serviced.