Fix for stuck tilt lock mechanism
Posted: Sat Mar 10, 2018 12:44 pm
The notorious tilt lock issues on the 9.9 yamaha continued to bother me and I finally fashioned a long attachment to 'mule' the lock lever into position. This worked for a year until the short plastic (delrin?) lever snapped on the port engine. I pulled the engine and of course the tilt tube was fused to the side brackets so I found a used one on eBay and ordered new bushings and a new lever. The old one would come out so I planned to cut it out. So first I made a couple of cuts thru the delrin lever along the axis of the tilt tube. Once I made one cut through, the lever started working easily. what?? It was still snapped to a nub so I went ahead and cut it out and then cut the old tilt tube (perpendicular) with an angle grinder. I 'persuaded' the parts apart and then applied heat and some tapping with a 2 lb. maul to get the old tube out of the aluminum castings. Putting is all back was very easy and the new lever from Yamaha was obviously redesigned to address the problem. The new one is larger in diameter so there is some play between it and the tilt tube. It is also made of a different plastic, is more rigid and it now as a port for lubrication.
With the port side fixed I contorted myself and using a mirror, cut a slit in the lever on the starboard engine along the axis on the tilt tube. One tap with a screwdriver and presto, the level worked back and forth easily.
My analysis for what it is worth? The original tilt lever is delrin or other synthetic that swells on prolonged water exposure. When it swells it squeezes down on the tilt tube (which also acquires rust over time) and this progresses until the the lever will not budge. By cutting the lever the squeeze is relieved and the lever works again like new.
I hope that the post helps someone. I think that the cut lever will continue to work well in that state but time will tell.
With the port side fixed I contorted myself and using a mirror, cut a slit in the lever on the starboard engine along the axis on the tilt tube. One tap with a screwdriver and presto, the level worked back and forth easily.
My analysis for what it is worth? The original tilt lever is delrin or other synthetic that swells on prolonged water exposure. When it swells it squeezes down on the tilt tube (which also acquires rust over time) and this progresses until the the lever will not budge. By cutting the lever the squeeze is relieved and the lever works again like new.
I hope that the post helps someone. I think that the cut lever will continue to work well in that state but time will tell.