Trim motor problem.

Took my boat to the lake, trim worked perfect until loading. When loading, it was really slow, like the battery was dead. When I hit the switch to raise the motor, it just sounded like it was hooked to a dead battery. I brought it home, the battery has 12.58V on the multimeter, so it is good. I raise the motor up a tad and it goes up very slow, again sounding like a dead battery, let it down, same thing. Then I raise it a little bit and it works perfect, then I lower it and back to slow. What could cause this?? Trim motor going bad? Low fluid?

This morning I hit the button and it worked perfect, then got sluggish, then just clicked at me, then I hit the button again and it worked perfect, then it got sluggish and never picked back up.

Motor is a 1990 Merc. 115HP

One of my buddies has a 115 merc. And his did the same thing. It turned out to be a little relay switch in the trim motor. He got a used one from
baily's marine at wax ky. And fixed it his self. (he owns a auto shop and towing service, so he had a garage and all the tools. Tr

I have a 1989 model 75 hp Mariner that the trim quit working on the "up" switch. I put a new relay in and no problem. It cost me about $20 for the switch. It would probably be a good idea if you changed out both of them.

Where are the relay's located and where can you buy them?

Thanks.

My guy got his at baily's boat service. In wax ky on nolin lake phone is
270-242-6293. You may find some closer, depending on where your located.
Any merc. Dealer ought to have them, or be able to get them..... Tr

Astrobass, mine are located on the right side of my engine. You can find them easy enough if you take cowling off and hit trim switch for a second. You should hear a click. They are simple to remove but make sure to unhook battery first.

Ok, took the cover off the motor, removed the plastic cover inside covering all solenoids. The trim solenoid is clicking and seems to be working. I trimmed the motor all the way up, engaged the lock position and let it back down on the lock. I removed the screw to the fill tube on the left side and I can't see a drop of fluid. So next step is to add fluid. What type of fluid do I use? I don't know when fluid was last added, the plastic screw that I removed was pretty tight and didn't have a single marking on it like it hadn't ever been removed before. I'm pretty sure that fluid may be my problem, hot weather and low fluid can't be a good mix. So I'll pick some up tomorrow and pour in. Last question for tonight: How far do I fill it?

I had same problem and it ended up being a bad ground connection,it done exactly what you described.

Not sure on how much fluid to add. I haven't had to do that since my first boat several years ago. I would just call a dealer or repair place and ask.

[QUOTE=wsbass;461780]I had same problem and it ended up being a bad ground connection,it done exactly what you described.[/QUOTE]

I'll check all grounds tomorrow as well.

[QUOTE=Carter1;461782]Not sure on how much fluid to add. I haven't had to do that since my first boat several years ago. I would just call a dealer or repair place and ask.[/QUOTE]

Check for an overflow port. That would be a small screw cap to remove. Fill untill fluid comes out of the overflow. Similar to the lower unit overflow port or a tractor hydraulic overflow port.

I would suggest having a mechanic do the repair as well. If you lost your fluid then you have a leak. Bad seal somewhere or a crack. A mechanic may be able to locate leak, replace an O ring or seal.

If you do it yourself check it out really good for a leak. Whe I check for leaks (in any number of situations) I place newspaper under and around the part suspect of leaking. If something drips on the newspaper it will show readily. May be one of the hydraulic lifts but they can be rebuilt.

That year model was notorious for having the brushes in the trim motor stick. Change out brushes and clean all the graphite out with compressed air.