Trim Gauge Not Working

I have a 1994 Baja with a 454 and Bravo 1 out-drive. While the tilt/trim works it does not register on the dash gauge.
First question... how do I check the gauge?
Second.. Assuming the gauge works ... what is the next step?

To check if gauge works (only works) is to jump between the send post and ground on the back of the gauge for a split second. Needle should jump from one side to the other. That is all you can do.


Next is the sender on the drive at the hinge pin location, gimbal ring, drivers side.

It is a variable resistor.............~ 60 ohms to ~ 280 ohms...........If I remember correctly.

Two wires come off it and the assembly is a b!tch to replace.

Two wires should connect into wire harness on motor.

I just replaced mine. correct, wires replacement done the right way means pulling the drive. There are youtubes on short cuts. if the wires are bad. What I did was just replace the insides with new parts $70. four screws outside and 2 screws which connect the wires inside the trim housings on each. assume wires are fine. 1 hour to do and recaliberate. you will know in 5 mins. if wires are bad.

Did you pull the outdrive or did you manage a shortcut without pulling it?

Boat needs to be out of the water, trailer is best. My drive stayed on for the gut replacement. But, You need to make some decisions. How old is the Gimbal, Shift, Exhaust bellows and water pipe. Up 0 to 5 yrs ok, maybe 7 yrs. to 8 yrs. maybe ok, older a change is necessary, check for softness, That is another Thread. If its brittle you should change and pull the drive. Do all the work together, along with new trim limit and sender wires etc. Or plan to do in the winter. You will take on water and possibly sink if any of the bellows crack, no way to stop water except continuous pump out. Ok, To get you thru the season. I went and bought a new Sierra trim sender/limit kit. Pay attention to how the parts sit inside the units, take pictures. Not alot of youtube videos on this or how to calibrate. What i did was, turn the wheel to the right, remove 4 small cover screws and take sender cap off, remove 2 screws hold sender to the drive. now the sender housing is hanging from the boat. There is a screw holding the contact in the sender to the wire, remove the screw. replace the parts from the new kit. be careful with the contacts as the tiny thin arms break easily. replace the contact to the wire (clean the wires and bare copper) and rebuild. after you have rebuilt one side, turn the wheel and do the other side. If you have a Selco manual it will tell you how far up to raise the drive to calibrate the limit, (you may need somebody at the wheel while calibrating, raise and lowering. There is also a baseline start point, my bravo iii is something like 20 3/4" bolt to bolt on the trim cylinder. Selco will explain. Unless you have done this many times you will need to go back and forth adjusting the trim and the gauge. also know that there is a full trailer setting. You don't want to include that height in the calibration, you could damage the drive shaft. If after you replace the guts of the sender/limit and you don't see any effects on the gauge even after you have tried adjusting. Then your wires might be gone or you have a bad gauge. inspect the wires. doubtful on the gauge. let us know how you did.

great post ..thanks ..now I just need to get some adjustment /calibrating instructions.

It is a rotary resistor like a home light switch used in a rotary illumination control.

There are two bumps, one on the center part that spins (fits into the gimbal hinge screw head) and one on the body, Trim outdrive all the way down to full down

Line up the two bumps, install so the slots line up with the screw holes preferable in the middle of the slots but if not no big deal then install two screws snug only!!

Turn ign on and see if gauge is at bottom or trim down. Now with key still on loosen screws and turn body clock wise or c'clock wise until gauge shows full bottom or down, then once that is done then adjust again until the gauge JUST starts to move ever so little. Once this occurs stop and snug screws again. Operate trim up and down to confirm gauge matches movement.

Need two people to do this. One watching and UNDERSATNDING what it is you are trying to accomplish and you to adjust the sender body.

Thanks much!!!

Did not check gauge yet but pulled the sender apart and it =s all toasted. Wire just broke apart at the sender and guts of wire are surface corroded black. What cause that and is the wire toasted or can it be salvaged? i see a lot of wires like that . Ordering a new sender set .

No slavage...gey a new one... splice it in to the existing wires where you can get clean connection

So here are some follow up questions for you. does the boat stay in the water your boating season or do you keep on a trailer or lift. i ask because if you splice the wires and they are not water tight.. you could introduce stray current into the water and that could introduce galvanic corrosion on your alum. metals, (outdrive). But then really how water tight is the trim sender/limit housing. so maybe that doesn't really make a difference. This applies to sitting in water and having shore power connection to the boat.

also, when was the last time your bellows were changed. If your rubber wires are in bad shape. your bellows could be also. just something to ask yourself and check.

The boat will be sitting in fresh water . You made some good points. I'll be watching for any leaks. I'm going to see if the wires can be salvaged but if not I will pull the whole out drive and rebuild everything before I put it all back together.