Trim cylinders only retracting halfway

[BigWeakSauce]

Good evening, shame on me I just started getting my boat ready for the season. I store the boat in my driveway and due to the angle of the boat on the trailer I keep the drive trimmed up about halfway to keep the skag off the pavement. When I was inspecting my bellows I noticed I could trim the drive up all the way but only back down to the level it was stored at. The last two years it was working fine. Tried adding more oil with no impact.
I did remove the aft pin and had my neighbor extend the rams while I held the ends in my hand and I noticed the starboard side was extending nicely but port side didn’t extend until I pulled the ram out with my hand, it extended to match the starboard. Both retracted normal but again only to the point where it was stored, about halfway.

Thoughts?

Edit** pre alpha drive, 1974 with Merc 165 IL6

 

[Tbird9191]

Good evening, shame on me I just started getting my boat ready for the season. I store the boat in my driveway and due to the angle of the boat on the trailer I keep the drive trimmed up about halfway to keep the skag off the pavement. When I was inspecting my bellows I noticed I could trim the drive up all the way but only back down to the level it was stored at. The last two years it was working fine. Tried adding more oil with no impact.
I did remove the aft pin and had my neighbor extend the rams while I held the ends in my hand and I noticed the starboard side was extending nicely but port side didn’t extend until I pulled the ram out with my hand, it extended to match the starboard. Both retracted normal but again only to the point where it was stored, about halfway.

Thoughts?

Edit** pre alpha drive, 1974 with Merc 165 IL6

Where you able to figure this out I am have similar problem with mine?

 

[ROY WILLIAMS]

the trim pressure motor had the motor was not working ...looked up the connectors and also remove the motor brushes and the armature had a bit of corrosion .. other trim cylinders had seals breaking down ..

 

[crazy charlie]

Grease the stainless part of the cylinders and help it in both directions.Do this several times .Charlie