150hp Mercury Hydraulic Lift Problem??

[Rusty]

I certainly hope someone can help me with a mysterious "lift" problem with my 150 Merc.

When under power, and trying to trim my 150 Merc., the engine will only tilt up a very few degrees. When not under power, say on the trailer or trolling with the kicker, it works perfectly. Full up and full down, no sweat. (This tilt problem is new, and the motor is 1 1/2 year old.)

The problem seems to be electrical as both switches, the one on the throttle handle and the one on the cowling of the engine will not lift the engine when the boat is up to speed.

I have the boat at Stevens Marine although they have not yet had a chance to look at it as they really are swamped.

Does anyone have any ideas? I am fairly sure it is not the hydraulic system, but maybe one of you ifishers has had a similar experience. I would appreciate a post or email.

Rusty, aka
Confused in Portland

[blast and cast]

I have had motors and other hydraulic equipment stop working due to low oil. My first check would be the fluid level in the system.

[Seefood Man]

I agree I would first check the fluid, however, it sounds like a pump problem. The pump doesn't have the ability to pump enough pressure when there is a load on the motor, but it does have the ability to lift the motor without a load on. It does not sound electrical at all, as you are getting full range of motion from both switches. This also rules out a problem with the limiter switches too. The first thing I would do is a pressure on the high end of the pump, (high end, the hoses that run into the bottom of the lifting pistons). Hope this helps

[Salmonator]

I'm not sure they are supposed to be trimmed while under full power? Seems like a ton of work for that trim unit...

[24 on/ 48 off]

I think the motor is only supposed to trim up a few degrees while in gear, thus preventing you from accidently pulling the intake out of water.

--spud-- :smile:

[Rusty]

I want to thank all you you who took the time to suggest solutions to my perplexing problem with my Mercury. They were all excellent ideas, most informative, and know doubt all valid possibilities.

After a care analysis, and conferring with Stevens Marine, I believe Seefood Man has hit the nail on the head. It does appear to be a hydraulic pump issue and not electrical or low hydraulic fluid.

Again, thanks to everyone who responded.

Gratefully,

Rusty

[SafetyChain]

I am experiencing the exact same problem. It is on a much older unit though ('76 150hp Merc) The power of the motor is keeping it from traveling full motion. Remember the prop is pushing towards the boat while the trim is pushing away. As it stands, 150hp is winning the battle over hydraulics.