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  #1  
Old 08-01-2009, 04:23 AM
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CDK CDK is offline
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Yamaha tilt problem

Somebody sought my help with the following:

His 2002 Yamaha 100 HP 4-stroke has hydraulic tilt and trim. Without any visible reason, the stroke is reduced to approx. 1/3 of what it should be. The engine cannot be lowered into a usable position and cannot be raised high enough to remove the trim unit.
Judging from the pump's sound, there is no mechanical obstruction, it seems like a bypass valve opens prematurely in both directions. We tried lowering it with someone standing on the engine and lifting it with two people helping, but that doesn't alter the length of the stroke.
The latter is a major problem because to gain access to the combined cylinder/pump, the engine needs to be almost fully raised.
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Old 08-01-2009, 10:51 AM
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Fanie Fanie is offline
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Hi CDK,

The power trim and tilt has a two stage operation. The lower stage (which I assume is the problem) is slow but powerfull to trim the motor down or suck it down on the water in choppy conditions. The upper stage is just to trim the motor out.

If I remember right there is a screw that can be loosened to allow air into the oil and it may be possible to push the motor up and down then. It may just be the oil level screw I'm thinking about but there is also a pipe like you get on brakes they can loosen.

Also by the sound of the position the motor is in it may be possible to take the T-pin on top of the cylinder rod out. The motor can then tilt up.

I took mine's unit out once to replace the motor's brushes, but that was about 200 years ago.

I just hope it is not the mechanical transport rest they are fighting there...
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  #3  
Old 08-02-2009, 05:39 AM
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CDK CDK is offline
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Fanie, to remove the T-pin you should have access to it. This guy's engine stays so low I can only touch that part with one finger.
And I don't feel comfortable sticking my right hand under a heavy engine with a defective tilt mechanism....
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Old 08-02-2009, 05:48 AM
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Fanie Fanie is offline
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Hi CDK, you sissy !

Support the motor and try to loosen the pipe fitting. If you let air into the hydaulics the motor should tilt up. It's either that or fetch the angle grinder.

Again, make sure there isn't something mechanical stopping the movement... Sorry to nag this point, but I've seen it happen. Lots of time and cussin later there wasn't anything wrong with the hydraulics, just a minor overlook on the owners part.
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  #5  
Old 08-03-2009, 04:03 AM
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CDK CDK is offline
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The tourist went home, leaving his boat in the water. He said people from a Yamaha service center will collect it later this week.
An excellent solution!
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  #6  
Old 08-03-2009, 06:34 PM
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pistnbroke pistnbroke is offline
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As fanie said there is an emergency release screw on the side so you an lift it ..access through a hole in the side of the clamp /mounting
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