1975 165 hp mercruiser tilt\trim won't go down

[rogerrabbitis]

I had all most run in to some rocks on the weekend but I had turned off motor and put drive up but we had bumped in to the rocks and one of my tilt cylinders broke off. sucked in a bit of water but drained got used cylinder now outdirve will go up with out an issue but down won't go down with out forcing it. (ie pressing in and someone standing on it) checked all wiring and went though bleeding process but no luck still won't go down any ideas?

few points
as it's going down with filler screw out of pump fluid will come out as being forced in.

believe I have a stuck valve but not sure where to look for it.

 

[achris]

Sounds like the seal in the end cap of the new ram has corroded up and is 'grabbing' the piston rod. You need to either replace that ram, or strip it down and replace the corroded parts.

Check the ram isn't bent.

Chris.....

 

[rogerrabbitis]

and what are you Achris considering the end cap the end where the lines go in . ? ya the ram is not bent if I crack the lines at the back of the ram fluid comes out and it will go down on it's own ! I seem to be having issue finding anything on the pump and anything that will show me the valves that controls the fluid it will go up with out an issue and start going down but will stop and only go down with assistance

 

[achris]

The pump has one line for UP pressure, and one line for DOWN pressure. At the bottom of the gimbal housing is a manifold which splits the 2 lines into 4 (one UP and one DOWN for each cylinder). So, if one ram goes up and down, the pump and it's valving is working fine. Check you have the lines around the right way.

The 'end cap' I'm referring to is the rod end of the ram, not the hose end.

Chris........

 

[rogerrabbitis]

Ok thanks for the info so both rams are going up but not down so I am looking at the valves then ?

 

[rogerrabbitis]

Sorry to add they will go up but will have to add force to go down press the in button and pump goes but nothing happens

 

[achris]

Check the lines are connected correctly. If you have them swapped on one ram, you get exactly the effect you are seeing. (It's due to the different surface areas of each side of the piston)

Chris.

 

[kenny nunez]

If the lines are connected correctly and the drive does not go down without having to be forced to do so then the ram is obviously the problem. Was it supposed to be rebuilt? If someone assembled it incorrectly or there are some internal parts missing then you have a problem. There is a 2 piece check valve that has small springs and tiny check balls, if any of them are missing could be the cause along with some sealing rings.