trim switch...which is correct....

[medic]

Did a search on this but could not find the answer. I am having trouble with my trim. 1982 OMC 2.5L It has been working fine, now it is hit and miss. After cranking it back down with a wrench and socket I was able to get it working. Again, hit and miss. Thinking it may be the selenoids as all I get is a clicking sound. When I try to short them out, using a screwdriver to jump the contacts, I get nothing. Not even a spark. Shorting out the tilt for the sterndrive works so I know the screwdriver is solid. The front of the engine was all the way up when this happened. I was able to make a few turn with a wrench and socket to bring it back down, then the switch starting working. All the way down now and it quit again. Does this sound like a selenoid problem or a switch?<br /><br />Also...when I hit the switch that says trim up, the front of the motor goes down. When I hit trim down, the motor goes up. Is this right? And what does trim exactly do? I have an idea.<br /><br />Thanks from another first time boater.<br /><br />Medic

 

[medic]

Re: trim switch...which is correct....

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[Boatist]

Re: trim switch...which is correct....

Medic<br />Trim on this motor raises and lowers the front of the engine to trim your boat. When you trim the bow up the front of the motor goes down. When you trim the bow down the front of motor goes up.<br /><br />Can be a bad solenoid, a bad trim motor, too much friction, lack of greese, front motor mount too tight, or a bad trim switch. Also if shorted wrong with screwdriver may hav blown the 50 amp fuse.<br /><br />Make sure you greese the motor zert fitting and the Jack Screw under the rubber boot. Loosen the front motor mount a little.

 

[medic]

Re: trim switch...which is correct....

So when I trim up, the motor goes down. When I trim down, the motor goes up. Which would provide a better ride and which would keep the prop in the water more? The reason I ask that question is that when I was cruising, there was a couple of times when it sounded as if I lost all power and the motor revved up. I throttled back down and the prop engaged and the boat would start moving again. The previous owner mentioned something about a slip engagement that occurs when the prop meets no resistance, such as when it comes out of the water. It disengages until you trottle down. I am wanting to verify this and to make sure I am doing things right. This boat thing is a first for me.<br /><br />Thanks...<br /><br />Medic

 

[medic]

Re: trim switch...which is correct....

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[Ralph 123]

Re: trim switch...which is correct....

Medic,<br /><br />Get a copy of the classic book, "Getting started in Powerboating" by Bob Armstrong. It will help you a great deal.<br /><br />To paraphrase him:<br /><br />Trim the drives all the way in before you start<br /><br />Advance the throttle(s) and advance smoothly to wide open<br /><br />When you get on plane, trim out until until you reach max speed or until the boat begins to porpoise; then trim in slightly<br /><br />Once you're there, throttle back to your cruising speed and fime tune the trim<br /><br />Remember:<br /><br />Triming the drive in adds to stern lift<br />Trimming the drives out adds to bow lift<br /><br />Get the book. It will help you greatly (at least it did for me)

 

[Doug Durako]

Re: trim switch...which is correct....

Medic---they used to all say trim "in or out" because that is what you are doing---moving the prop in closer to the stern of the boat and deeper in the water. Trim out moves prop further away from the stern.<br /><br />Trim all the way "in" to get the boat on plane.<br /><br />Once on plane at about 2800 rpm:<br /><br />When you trim in, bow of boat goes down and you plow the water. You should feel the difference. Same RPM moves the boat slower because more of the boat is in the water.<br /><br />When you trim out, bow goes up. Same RPM moves boat faster because less of the boat bottom is in contact with the water.<br /><br />Most trim units say "up or down" on new boats, cause that is what the bow does and it is less confusing.<br /><br />If engine revs when you trim out, your prop has ventilated (sucked air) and you need to trim back in until it "catches" water. Most likely, this happened on a sharp turn or at Wide open throttle.

 

[medic]

Re: trim switch...which is correct....

Now I understand. Thanks for the help.