No one on either of the boating forums I've posted this thing on seems to know how OMC?s tilt assist cylinder is built - lots of reads though. However, if it's as I've assumed, it should relatively cheap/easy to fix & therefore profitable to anyone willing to attempt something different (EBAY/AMAZON sell 1/8 NPT shrader valves for ~$3 plus you'll need a half pint of generic hydraulic oil). Here?s how I would go about doing it:
1) release the motor?s tilt assist (move the lever stern-wise) and ? muscle? its lower end all the way up & tie its power head to the boat?s bow/seat so it can't fall back. Then carefully crack open the trim assist cylinder's upper plug screw to release gas that has gotten past the piston?s seals. Since such gas is likely to have pressurized the outside reservoir, most of the hydraulic oil ?approximately one half pint - is apt to be lost as well (much less would be lost if the cylinder were to be removed from the motor and turned upside down before that screw is removed). Inject approximately the same amount of fresh oil back into that opening with a syringe, apply gasket sealer to its plug screw, and screw it back in. (An additional engineering improvement to OMC?s system would be to add a tiny gas vent at the top of its outside reservoir to prevent such reverse pressurization. Its opening would also provide a more convenient oil fill point ? a $626 gas-filled bottle jack should be ?maintainable?.)
2) carefully remove the lower plug screw (there's almost certainly still some fairly high pressure gas left under the piston)
3) if that hole isn't already threaded for your shrader valve, do so (most tap/die sets include the necessary tap). If it?s necessary to ream it out first, use a 11/32? drill.
4) apply gasket sealer to that valve?s threaded end & screw it in tight
5) pressurize the cylinder with argon or nitrogen until it's able to hold the motor up by itself (i.e., put some slack into your tie-off rope). This will probably require over 300 psi ?beyond the upper range of most gas regulators - which likely means that your fill hose will have to be connected directly to the Ar/N[SUB]2[/SUB] tank?s valve - ?tweak? the latter to pressurize.
6) untie the rope & repeatedly tap the shrader valve's sealing pin until enough pressure escapes to allow the motor to completely settle down under its own weight.
7) Test for leaks by tilting the motor back up, locking it by moving its tilt assist lever all the way forward, and putting soap solution on the cylinder?s valves & seals ? if you don?t see bubbles & the motor stays put, you?ve fixed it.
8) charge whatever you think is fair but please tell your customer that your next fix is apt to be both quicker and cheaper.
The really "tough" part about this for a non professional is getting a tank of N[SUB]2[/SUB] or Ar to pressurize with; however, anyone with MIG/TIG (aluminum) welding capability probably already has it.
If anyone decides to give this a shot, please let us know how it worked out.
opcorn:
