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Power Trim not working

canaltrash

New member
I have a 2000 Bayliner 185 with a Mercruiser 3.0. Problem started when Red cable from battery to starter corroded and broke apart.

I have since replaced the cable and then the starter. However now my trim has nothing and the outdrive is down so I cannot take out of water.

I checked the fuse at the Trim motor, it is good. What would cause me to not have anything, no up, now down, or no trailer. Not even a click?
 
The power and ground cables to the trim assy. are suspect.
How the trim/tilt works

Before you tear anything apart or replace wiring and switches, test it out; first by visual inspection by pulling back and forth on the wires while operating the switches and then test with a meter. At the commander switches, the red wire will always have 12 volts. The green wire gets 12 volts when the trim toggle is held down. The blue wire gets 12 volts only when the toggle is held up or the trailer switch is pushed in. The purple wire is part of the limit switch circuit.

If the switch voltages are as they are supposed to be then go to the trim/tilt pump assy. and make sure the purple wire connector (single wire) and the blue wire connector with two blue wires on one side of the connection are not corroded or loose. These are the trim position and limit switch wires. Pull them apart and inspect; they should be clean and tight; reconnect them. If necessary, trace the wires to the front of the engine near the slave solenoid. One wire is grounded near there and the other is connected to a terminal. If you don't get a voltage reading at the terminal junction, apply 12 VDC to see if the trim gauge moves. If it does, check for voltage back at the trim pump connections. If no voltage is there, apply 12 VDC there to check gauge movement.

Next check the three wire connector (RED, BLUE & GREEN) at the pump assy. This plug can vibrate loose and cause your problem. Pull it off and see if the pins are clean and not corroded; reconnect it.

The RED wire in the plug sends 12 volts from the pump assy. to the toggle up/down and trailer up switches. The BLUE & GREEN wires bring 12 volts from the toggle trim/tilt and trailer switches to the two solenoids on the pump assy.

The GREEN wire goes to the DOWN solenoid while the BLUE wire goes to the UP solenoid.

Did you check the switches with an ohmmeter? The trim/tilt switch is a 2-way switch and will show continuity only when it is toggled in each direction between two of the wires.

Up toggle connects the RED wire to the BLUE wire. Down toggle connects the RED wire to the GREEN wire. The TRAILER UP switch also connects the RED wire to the BLUE wire.

The OD trim limit switch will only send voltage to the trim/tilt switch in the upward toggle position if the OD limit switch is below the adjusted trim limit that keeps the OD being out of the water.

To test the limit switch circuit, lower the OD to the down position and slowly raise it with the trim toggle up until it stops. Then measure the distance between the trim cylinder attaching bolts. If the distance is approx. 22 +/- 1/4 inches, then the trim limit switch is adjusted properly and the commander trim toggle switch is working in the up/down mode.

Go to the trim/tilt pump assy. and make sure the purple wire connector (single wire) and the blue wire connector two blue wires on one side of the connection are not corroded or loose. Pull them apart; they should be clean and tight; reconnect them.
Next check the three (RED, BLUE & GREEN) wire connector at the pump assy. The RED wire in the plug sends 12 volts from the pump assy. to the toggle up/down and trailer up switches. This plug can vibrate loose and cause your problem. Pull it off and see if the pins are clean and not corroded; reconnect it.

The BLUE & GREEN wires bring 12 volts from the switches to the two solenoids on the pump assy. The GREEN wire goes to the DOWN solenoid while the BLUE wire goes to the UP solenoid.

Disconnect the trim/tilt assy. wires from the battery and then check each of the nuts and studs on the solenoids for clean and tight fittings. Each solenoid has three wires and the buss bar connected to it. The bases of them have a black ground wire and a small blue wire to one and a small green wire to the other.

On top of each solenoid, the large BLUE wire from the pump motor attaches to a large copper stud with the solenoid that has the small blue wire at the base while the large GREEN wire from the pump motor attaches to a large copper stud with the solenoid that has the small green wire at the base.

The other copper solenoid studs are connected together with a copper buss bar. One of the two studs will also have a funny looking 110 amp fuse attached to the bar. The large RED wire from the battery connects to the 110 amp fuse. This large red wire is the power for this buss bar. A small RED wire attached to the bar stud sends 12 volts to the switches which in turn sends the 12 volts to the solenoids which turns on the pump motor.

Important: if the studs on the either solenoid are dark and not like a clean penny, especially the BLUE wired solenoid, this solenoid is failing due to age and/or a loose bottom copper stud nut. The dark color comes from heat generated inside of the solenoid by the contactor because it is arcing like welding similar to points wearing out. Change the solenoid.

Cleaning Trim Limit Switch & Trim Position Sender

For the trim/tilt problem you are experiencing, if the wires from the limit switch (port side) and trim position sender (starboard side) are in good condition, they (Switch or sender) can be disassembled to clean out the old hardened grease. SCRIBE the sides of each one and the OD for a reference mark before removal. Clean out the old grease and pump fresh Mercruiser 2-4-C grease thru the zerk fittings before reinstallation. Clean the small brass contact points with solvent and a pencil eraser until shiny; repack w/ 2-4-C grease and reinstall by aligning reference marks.
 
My 1982 pre-apha drive has a manual lift crank, I would assume a 2000 Alpha 1 Gen II would have one as well? At least to get your boat out of the water so you can work on it.
 
I know that this may sound rather basic but if the drive won`t even click, check to make sure your gear shift isn`t slightly passed neutral towards the reverse position. I`ve had this exact thing happen to me and it was not having the shifter in neutral. Trim motors are designed not to work in reverse.
 
DESPY,

The trim system is designed to work totally independent of all other circuts in the boat. It works ALL the time. It works in forward, neutral, and reverse.

The old old old OMC stringer drive may have had that issue but not the mercury's.

You also may be thinking of the old REVERSE lock out valve attached to the shift cable that would not allow the drive to kick up when shifted in reverse......

All current trim systems work all the time in any gear.
 
I don't have one on my Alpha 1 Gen I.

Really? There is not "Manual Tilt Knob" located on your trim pump motor? Maybe I'm just lucky.

I can't seem to upload anything on this forum or I would post a page from the 470 owner's manual showing it. I'm not liking this new forum style.
 
"There is not "Manual Tilt Knob" located on your trim pump motor?"

That is correct. I've had it all apart; no knob.
 
"There is not "Manual Tilt Knob" located on your trim pump motor?"

That is correct. I've had it all apart; no knob.

Curious what brand you have. I'll check mine next time I'm in the boat but I assumed it was Mercruiser brand. Mine is a 1982 470 package with a Pre-alpha R, MR package. I always thought the manual lift over-ride was a great idea if your wiring ever conked out and you needed to trailer the boat.
 
Well , isn`t that strange. Twice I have pulled my boat onto my trailer and went to raise the leg and the trim motor would do nothing, not even click. As soon as I realized I had left the boat in reverse and shifted it back to neutral , it worked fine.
While it was in reverse, it wouldn`t even make a sound.
 
If the trim will not work when shifted into any gear the wires in the handle/control have a issue..............
 
pretty basic, but what about the hot lead from the battery to the trim bus? Did it get reinstalled when the hot side for the battery was replaced?
 
my bayliner had a circuit breaker on the positive feed into trim relays. If the breaker popped then the system was dead until I pushed the little red "reset" button.
 
I have a simlar problem w/ 84 sea ray 3.0 liter 4 cyl , it sounds like a limit switch issue, the trim will go all the way down and only 3 or 4 inches up before it stops. I looked at the the trim motor and it is an sae j1171 marine pump, but I did not notice a reservior, am I missing something? thanks:)
 
This would make a great STICKY topic. I brought this up on the old board format and it couldn't be done but how about this new format? Andrew?
 
hey guys,

i'm having problem with my trim pump on a '68 fiberform with a mercruiser sterndrive... do most of the same test principles apply here, or are the old pumps completely different? I bought the boat with the trim issues.. the PO had filled the pump up with fluid and it dumped all over the bilge. i pulled the gimbal housing trim connector (i think that's what it's called), and metal was completely disintegrated where the two upper hydraulic fittings attach. i assumed it was leaking here and dumping through the transom into the bilge. i replaced this part, but the trim pump does nothing but click when i push the "trailer" button. the UP button send power across the solenoid without the click, but the pump doesn't seem to do anything.

new pump? is there a way i can test this one to make sure it's bad?
 
trim pump does nothing but click when i push the "trailer" button. the UP button send power across the solenoid without the click, but the pump doesn't seem to do anything.

The pump motor is shot. You can get a new motor and pump from http://bpi.ebasicpower.com/c/MER3A/Trim+&+Tilt+Motors+&+Parts+for+Mercruiser The entire assy. has had 42 yrs. of wear. Consider replacing the entire assy. I would also replace the trim/trailer switches and the solenoid.
 
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