I have a 1974 mercruiser 120 hp . I believe it's an MC 1 outdrive. Had erratic trim performance then it stopped going down. here is what i have done so far....
1 Oil was milky so I flushed it with lots of oil...good now.
2 Ordered a kit to rebuild cylinders...wrong kit so i used as many o rings as would fit. the back scraper seal thing fit.
3 replaced a leaky connection block and the 2 hoses on one side
4 bled the system repeatedly. must have run a gallon of oil through it since I started.
The cylinders go in and out smoothly with a hose disconnected but won't retract with the trim pump. I have flow from all hoses when disconnected.
I'm thinking it might be a valve sticking in the pump. can this be repaired or rebuilt? I was looking at new pumps but they all said to use your old valve body. that's no good to me if that's where the problem is. I believe it is a Prestolite pump. It has a square reservoir with a fill screw and a vent screw right above it.
Please help!! I would like to get on the water this long weekend!!
1 Oil was milky so I flushed it with lots of oil...good now.
2 Ordered a kit to rebuild cylinders...wrong kit so i used as many o rings as would fit. the back scraper seal thing fit.
3 replaced a leaky connection block and the 2 hoses on one side
4 bled the system repeatedly. must have run a gallon of oil through it since I started.
The cylinders go in and out smoothly with a hose disconnected but won't retract with the trim pump. I have flow from all hoses when disconnected.
I'm thinking it might be a valve sticking in the pump. can this be repaired or rebuilt? I was looking at new pumps but they all said to use your old valve body. that's no good to me if that's where the problem is. I believe it is a Prestolite pump. It has a square reservoir with a fill screw and a vent screw right above it.
Please help!! I would like to get on the water this long weekend!!
