85 johnson hydraulic tilt settleing

[75starflight]

Asking a question for a friend of mine. he has a older 85hp Johnson with the add on hydraulic tilt system we believe part number 0172189. He has not used the boat for a couple of years and the hydraulic tilt system will raise the motor but once raised the tilt system will settle and takes about a minute to completely go down. Any thoughts on what to look at?

[thedeuceman]

the one on our GT did that, i took the pump apart twice and cleaned all the valves but still leaked down. it was the day before the meet so i cobbled a mercruiser pump on and decided i likes that better.

first thing i would do is check that the bypass valve is screwed all the way in.
then dissemble and clean it, if i remember correctly there is a check valve inside the pump.

that being said, there may be a kit available for it, somewhat depends on which pump it has.
i think ya can get parts for the presto-lite pump but not the other style.
i have also herd that a pump off a force trim unit will work just need to plug 2 of the lines.

[Plugcheck]

If it hasn't been used in awhile seals may have dried up or bit or something like the valves are not closing completely.   If it were me, I'd cycle it a few times up and down, then change the fluid, and cycle it a few more times.  If no leaks are visible and it continues to bleed off, then the pump or cylinders are suspect.  Personally, I'd go after the pump. 

[V153]

My bet would be the cylinder(s) leaking internally.