2001 Larson 180 SEI, Trim Switch

scottrappley

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Jul 9, 2018
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On my throttle lever there is the normal up and down trim switch. On the lever there is a trailer trim switch as well. When I bought the boat the guy said the "up" does not really work but the down does. He just uses the trailer trim switch to raise the trim when necessary after getting up on plane. Is there any issues with doing this? Thinking I should look in to possibly getting the switch replaced in the upper portion of the lever. I would expect that button to raise and lower the trim and the trailer is only used for bringing the prop all the way up. Can anyone chime in on this on how it is supposed to work and whether I should look into replacing anything if necessary?
 

tpenfield

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It is usually the limit switch on the outdrive that is the cause of the problem, not the switch on the throttle.
 

JASinIL2006

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Ted is correct that this is almost always a problem with the trim limit switch rather than the switch on your throttle handle. Sometimes a bad solenoid can also cause trim control problems, but in the case of raising the drive, a bad solenoid would also interfere with the trailer button working correctly. Since the trailer button works, but not the trim up button, the trim limit switch becomes the most likely culprit.

There are several ways you can handle this.

First, you can ignore it and just use the trailer button to raise your drive. This will work just fine, although your 'trim up' button on the throttle won'w work and you won't have any protection against accidentally raising the drive too far while the engine is turning the driveshaft. Raising the drive too much under power can problems with the U-joints in the outdrive. (The U-joints will make some noise when you trim too much under power, but it's best not to get to that point. Raise the drive too far while the engine is on, and you could trash your U-joints.)

Second, you can disable the trim limit switch pretty easily. There is a bullet-plug connection between the wires going thru the transom to the trim limit switch and the wires to the controls on your throttle. A very simple homemade jumper can be used to eliminate the effect of the trim limit switch. This allows your 'trim up' button to work but without any protection against trimming the drive too high. In essence, with those wires jumpered, the trim up button will function exactly the same as your trailer button, and with the same risks if you trim too high.

Third, you can replace the trim limit switch on the outdrive. This really requires some disassembly of the transom assembly and is easiest to do when you're having your bellows replaced (which most people do occasionally anyway).

I chose to bypass the trim limit switch using a homemade jumper and then I just replaced the trim limit switch a year later when I had to do the bellows. If your trim gauges works and you're careful not to raise the drive too far, it works fine. (In fact, some guys just jumper the connection and leave it that way permanently.)

Hope this helps!
 

scottrappley

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Jul 9, 2018
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I am going to look at this more in detail tonight. Personally I would just like to get the up to function with the button at the top of the throttle lever. Years ago I used to have a 201 liberator and it never had 2 buttons for the trim, just the one. So really I am more used to just using the 1 button anyway. I am very familiar with electrical but where and what did you jumper? If you could elaborate a little more on that I would appreciate it. I am guessing you jumpered the trailer up wire to the up button on the throttle lever. If so, did you tear apart the throttle lever to do this? Any help is appreciated. Thanks.
 

tpenfield

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Don't tell anybody, but I jumpered the trim switch on my outdrives. As I recall there are male/female connectors at the back of the engine and you'll see the wiring (black) lead to the transom assembly just above the drive shaft. there is a pair of wires for the trim sender and a pair of wires for the trim switch. IIRC, I just connected the trim switch leads together rather than to the trim switch wires.

You just need to keep an eye on how much you trim up while underway.
 

scottrappley

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Ok well I figured out the trim switch problem and did not cost any money. :)
On the port side of the outdrive there is a trim pot located behind a 4 screw plate. You have to turn the outdrive to one side to access this panel. Once I removed the panel there is a copper contact bar. Both of these pieces were completely corroded. Other articles have stated they get clogged with grease as there is a grease port right inside the keyway. Mind did not have a grease problem just a corrosion issue. Upon cleaning all of that up I made sure the keyway was clocked in the right position on the spline. Basically you can move the contact point to different positions and this is what actually allows you to trim up on the throttle. As long as the copper point makes contact on the copper bar the trim up will function. I also went on the other side of the outdrive and removed the same panel but this side is what controls the position you gauge will indicate. You can adjust that as well to make sure the gauge is indicating correctly. Once I did all that everything tested ok. Really was not that bad once I got in to it. Had I not seen some information from youtube I would not have ever known about these simple adjustments. Hopefully this may help someone else out as it did myself.
 

tpenfield

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You can adjust those senders/switches without taking them apart. The screws in the slotted portion of the senders loosen for fine adjustments.
 
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