Power Trim and Tilt Unit

In the newly designed PTT unit, the up-main valve, down-main valve, up-relief valve, and downrelief valve have been concentrated in the gear pump housing in order to improve the serviceability of the engine and ensure reliable operation.

Power trim and ilt

1 Tilt cylinder
2 Trim cylinder
3 Manual valve
4 Up-main valve
5 Down-main valve
6 Up-relief valve
7 Down-relief valve
8 Gear pump
9 Reservoir
10 Tilt ram
11 Tilt piston
12 Tilt piston absorber
13 Free piston
14 Shock return valve
15 Trim ram
16 Trim piston
17 Power trim and tilt motor
18 Up-shuttle piston
19 Down-shuttle piston

Trim-up and Tilt-up Function

When the PTT switch is pressed to “UP,” the Power Yamaha  Trim and Tilt Motor operates the gear pump and fluid pressure is generated. As a result, the fluid pressure pushes the up-shuttle piston upward, enters the trim cylinder and tilt cylinder lower chambers through the up-main valve, and then pushes the tilt ram and trim ram upward.

In addition, the fluid pushes the down-shuttle piston downward, opens the down-main valve, and returns the PTT fluid from the tilt cylinder upper chamber to the gear pump. The fluid from the trim cylinder upper chamber then returns to the reservoir.

The tilt ram and the trim ram extend simultaneously, and after the trim ram has extended completely, the tilt ram operates to tilt up.

Trim-up and tilt-up function

1 Tilt ram
2 Tilt cylinder
3 Trim ram
4 Trim cylinder
5 Power trim and tilt motor
6 Reservoir
7 Gear pump
8 Up-shuttle piston
9 Up-main valve
10 Down-shuttle piston
11 Down-main valve

It’s easy to overlook the importance of the Yamaha Trim and Tilt unit on your Yamaha outboard motor, but it’s one of the most essential components for getting the best performance out of your boat and motor. Tilt and trim adjust the angle of the motor and thus the running surface of the boat, so they determine the smoothness of the ride, the grip on the water, the ability to jump on plane and many other operations that you often don’t even think about.

For instance, when running across a lake where you have to run through a lot of thick grass, the ability to trim your engine level (about halfway up) allows you to avoid pulling weeds into your water intake and overheating the engine. The same goes for running in rough seas where the ability to trim the engine all the way down allows you to keep the bow close to the water so you end up with a smoother ride and don’t pound into the waves.

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