I have an Evinrude 110 hp outboard 1989 model

The power trim/tilt system has a problem.

I can raise and lower the motor without any problem, with the outboard
motor not running or with the boat moving at slow speed.

While moving at speed, the up trim does not work (I can not hear if
the ram motor runs due to engine noise).

There does not appear to be any oil leaks around the rams.

If I trim the motor up while moving slowly, then accelerate, there is
a 'clonk' sound as the thrust from the prop forces the motor 'down'.

I checked the ram fluid level with the motor in the up position (on
the motor support) the trim rams were fully retracted (in) - a small
amount oil escaped out of the filler plug hole.

I then checked the level with the rams fully extended (out) and no oil
escaped through the hole. I will top up the fluid with the rams in the
fully out position.

I lowered the motor onto the trim rams and stood on the cavitation
plate above the prop and bounced on the motor to see if I could cause
it to move down further - no luck with that test.....

Can you determine from the description above what the problem might
be? If not, what would be the easiest starting point in the process of
elimination?

To me, it appears that the system can not hold pressure - hence the
'clonk' when accelerating - assuming the pump is running while at
speed (can't see why it is not running, considering it runs ok at slow
speed and stationary).

Looks to me as if there is a valve problem or bad internal seal(s)...

What would your first point of 'attack'

Thank you for your time and your help

Regards,

Jim Stapenell
7 Beneve Court
Montrose Tas 7010
(Australia)

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