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77 OMC Trim and Tilt Questions

steamin53

Member
I need some help guys. We bought a 1977 70 hp Evinrude with Power Trim and Tilt. This is the system with the rams outside the engine bracket.

The port (trim ram I've been told) was frozen in place. The motor, pump, and starboard ram all work.

I've acquired another system and in testing on receipt I find that the motor worked, the pump extended the starboard ram but not the port side. In a third sequential cycling of the sytem at the end of the starbord ram's travel the port side ram extended about 4 inches then it stopped. Reverse the system and the starboard ram retracted but the port ram does not and it feels like it is solidly locked where it is.

I've been told that the port ram has no hydraulic pressure to it at all which seems to be impossibly or unlikely at best since it has a hydraulic line to the bottom of it. I conclude that since the starboard ram has hydraulic lines to the top and the bottom it has hydraulic power both to extend and to retract and that perhaps the port side only has power to extend.

Either way, I'm concerned now since the port ram won't retract no matter how hard I push on it with my hand.

Anyone able to advise me on this?

I SHOULD ADD THAT THE SYSTEM IS NOT MOUNTED ON THE ENGINE FOR THESE TESTS. I wonder if the port ram requires power from the starboard ram in the retract mode to go down?

Steve
 
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