Tilt and trim goes down but not up

Your outboard drops fine but will not come back up. Or it lifts and refuses to go down. Either way, the fact that ONE direction still works is the most useful clue you have, and it usually points away from the motor.

Up and down are not one circuit. They run through separate relays, and on most systems the motor is reversed by swapping polarity through those relays. So a single direction failing means something in that direction's path has failed, and the motor itself is generally fine.

Here is the order to check things in, cheapest and most likely first.

1. Fluid level

Low fluid gives you a motor that runs and a ram that does not move, which is easy to mistake for a dying motor. It also explains a unit that works intermittently or feels weak.

Trim the unit fully down, find the fill plug on the reservoir, and check the level with the engine upright. Top up with the fluid your manufacturer specifies. Most tilt and trim systems take ATF or a dedicated trim fluid, and they are not always interchangeable.

If it was low, something let it out. Look for weeping around the ram seals and the hose fittings before you call it fixed.

2. The relays

This is the most common real fault, and the easiest to confirm.

There are two relays, one per direction, and they are usually identical. That makes the test simple: swap them with each other. If the fault moves to the other direction, you have found a bad relay. If it stays put, the relays are fine and you can move on with certainty.

You may also hear the difference. A working relay gives a distinct click when you press the switch. Silence on one direction and a click on the other is the same answer.

3. Grounds and connections

Salt water is relentless and the trim system sits low. Check:

• both battery terminals, cleaned to bright metal
• the ground from the engine to the battery
• the connector at the motor, which is often the first thing to corrode
• the trim switch connections at the helm and on the cowling

Green powder anywhere in that path is enough to stop one direction while the other still works, because the two paths do not share every connection.

4. The switch

Most boats have two switches, one at the helm and one on the engine cowling. If one works and the other does not, the switch is the fault, not the motor.

That is a genuinely useful test and it costs nothing.

5. The motor

Only now is the motor the likely suspect. Signs that it really has failed:

• no sound at all in one direction, with a confirmed good relay and voltage arriving at the motor
• a hum or a groan with no movement, which is often a seized armature or stripped brushes
• it works when you tap the motor housing, which means worn brushes
• it ran hot and then stopped, which usually means it is done

Confirm with a meter. With a helper on the switch, check for battery voltage at the motor connector in the failing direction. Voltage arriving and nothing happening is a failed motor. No voltage arriving means the fault is still upstream, in the relay, switch or wiring.

Why one direction wears out first

Lifting takes far more current than lowering. The motor is fighting the weight of the engine on the way up and gravity is helping on the way down, so the up circuit does most of the work and its relay contacts and brushes wear first.

That is why "goes down but not up" is the far more common complaint of the two, and why it so often turns out to be the up relay rather than the motor.

Motor, pump or complete unit

Tilt and trim assemblies are sold three ways and the parts do not interchange:

• the motor alone, which is what most of these repairs need
• the pump, the hydraulic half, when the motor spins but nothing moves and the fluid is full
• the complete unit, motor and pump and reservoir together

If the motor turns freely and the fluid is correct but the ram still does not move, you are looking at the pump rather than the motor.

Match the number on what you are replacing before ordering. These vary significantly between manufacturers and model years, and a unit that looks identical can have a different shaft, mounting or plug.

Making the new one last

The wiring that killed the first motor will happily kill the second. When you fit a replacement:

• clean every connection in the circuit back to bright metal
• protect the connections with dielectric grease or heat shrink
• check the ram seals are not weeping, since fluid loss will strand you again
• make sure the motor drains properly and is not sitting in water in the well

Marine units are built for the environment, but nothing survives a permanently wet connector.

Finding the right part

The number on the unit you are removing beats a model year, because the same engine was often built with more than one trim setup over its production run.

Put that number into our cross reference lookup and it will find the match across every brand we hold. You can also browse tilt and trim motors directly, or start from your engine.

Every unit we sell is new rather than remanufactured, carries a one year warranty, and ships from USA.