Trim up not working, trailer works

[boat4fun83]

I have a couple questions....
First of all my engine is a '96 GM 350 with Mercruiser Alpha one gen II lower unit. I am pretty handy and I have fixed pretty much everything else that was wrong.

Last couple things I need help with are.. I am able to use the trailer button to raise the lower unit but the trim up will not work. Trim down works. Trim gauge does not work either. Is there any way to check the wiring without taking the lower unit off?

I also have a battery switch where you can switch between battery one and two. Battery two does not work. Both batteries have been checked and they showed 96 percent. I changed the cable connection thinking that was the problem from the toggle bolt to the terminals. Is this a bad switch or what? I have checked the ground and it appears the same as the other battery.

 

[blg2007]

Re: Trim up not working, trailer works

Hello,

Does the trim up not work at all? The trim up is only for running the boat down the water, to adjust for your conditions. It will not raise the unit all the way up. If it is not, check the solenoids on the trim pump, there will be two. This is probably your problem.

 

[cooter2506]

Re: Trim up not working, trailer works

MOst likely culprit is the trim limit switch on the drive. It s either bad or the wires are broken to it. Go to the drive and swivel it to the sides and with a flash light look into the gimble housing at the wires from the limit switch(port side I think) see if they are broke. If they are dont just crimp them together. replcace the switch and follow instructions. Electrical connectors dont like the water.

 

[IVAZ]

Re: Trim up not working, trailer works

I agree with cooter. It seems like a common issue on many boats. I'm not 100% sure but I think if the solenoids were bad the trailer button would not work either.

 

[boatguya1]

Re: Trim up not working, trailer works

I agree with cooter. It seems like a common issue on many boats. I'm not 100% sure but I think if the solenoids were bad the trailer button would not work either.

You and cooter are correct.

James

 

[cannonford57]

Re: Trim up not working, trailer works

cooter and ivaz,thumbs up....but consider another possibalty ,the up side of the $0.35 cent switches mcm seems to be using for a while,just a thought

 

[boat4fun83]

Re: Trim up not working, trailer works

Thanks for the pointers. I will check it out this weekend at the lake. From what I remember last year, it would barely go up with the trim up like maybe a millimeter so I am guessing it's the trim limit switch. To replace the trim limit switch does the whole lower unit have to come off?

Any pointers on the battery switch?

 

[IVAZ]

Re: Trim up not working, trailer works

If the wires for the trim limit switch are still good (you have to check for current and abrasions) you simply remove to screws and put a new one on. If the wires outside the transom are damaged, you have a huge job ahead of you (not worth it). If the wires are still good and you decide to put a new one on, the "adults only" sticky has the manual you can download to show you how to set it.
I'm not sure about the battery switch. You can probably do a search in the electronics section and find your answer.

 

[bamadave]

Re: Trim up not working, trailer works

Disconnect the limit switch in the engine compartment and jumper the leads going to the trim pump together, the trim switch should work then.

 

[boat4fun83]

Re: Trim up not working, trailer works

What are the jumper leads at the trim pump? Are they the actual black leads coming from the trim limit itself b/c would that just create a closed circuit that would not run anything. Sorry I am confused. Please describe what I may see if possible.

 

[boat4fun83]

Re: Trim up not working, trailer works

Update.

I get nothing when I push the trim up button. Any suggestions?

 

[gadget73]

Re: Trim up not working, trailer works

There should be a pair of black wires at the trim pump. It will look sort of like a lamp cord, but with a male and female connector on them. Those wires will vanish somewhere at the transom assembly. Unplug these, and connect the pump side wires together. If the trim works, the issue is in the limit switch or it's wiring. You can run like this, but be aware that with no limit switch, you could possibly crank the drive all the way up to trailer position while running, and that would not be a good thing.