"Trim Senders" not responding

[BlueNote2]

Hi,

I bought a boat last summer and previous owner warned me that the trim/tilt did not always respond.

I was thinking maybe I need to replace the "hockey-pucks". ?
It worked fine until today (I was preparing to do an impeller replacement) but unit will not move up, only goes down.

Where can I find part numbers for my boat? 1987 SeaRay 190BR, 3.7 Mercruiser 470 (165hp).


What about this?:
https://www.youtube.com/watch?v=Q70Fc2gWgZQ

 

[JaCrispy]

If it doesn't go up with the trim or trailer switch then you might have a bad connection on the pump or the switch or a bad up solenoid. You can try eliminating the switch/wiring by jumping the red and blue wires on the 3 prong connector on the pump. I had some corrosion in that plug.

 

[BlueNote2]

thanks, JaCrispy.
I just checked... the "Trailer" button works, but not the "up" switch

 

[BlueNote2]

what is the "3-prong connector"? Where would I locate that?

 

[alldodge]

what is the "3-prong connector"? Where would I locate that?

The three prong plug is on the trim pump and can go bad

 

[BlueNote2]

@AllDodge,

Thanks. the illustration is very helpful.

 

[JaCrispy]

thanks, JaCrispy.
I just checked... the "Trailer" button works, but not the "up" switch

If the trailer button works the 3 prong connector is good.

Can you locate the two wires going into the trim limit switch (puck on port side of drive). While operating the trim up button, put a test light on the wires (seperately) and see if you get power to one of them. If so, the limit switch is bad. If you don't get power to one wire then you have a bad switch or wiring between the trim switch and trim button.

Also, operating the trailer buttom will light up the other wire on the limit switch (puck).

 

[achris]

thanks, JaCrispy.
I just checked... the "Trailer" button works, but not the "up" switch

Remove the wires that go into the harness from the trim limit switch ('h' in the wiring diagram) and join the harness with a short length of wire. If your UP button now works properly you have 3 choices... 1) replace the offending switch. comes in a kit with both switches and their associated wires. Attempts to repair the switches usually fail. Also DO NOT just cut the wires and try and join the new switch onto the old wires. Merc supply the switch with its full wires for a reason... 2) remove the shorting wire and run with the system as is, being aware that to get the drive to trim or go all the way UP you need to press the TRAILER button. Most people don't do this one. 3) Leave the shorting wire in place and just use the UP trim button to get the drive UP. Being aware that with this configuration you can run the drive out of the gimbal support. Operate with caution. Replace the switches when you're doing other work on the gimbal area that will allow easier access, like when you go to change the uni joint bellows. This is the option taken by most people....

HTH,

Chris........

 

[BlueNote2]

@ achris, thanks.
What about opening the Trim Limit Switch and cleaning the connections and adding dielectric grease?

---

Assuming I need to replace the Trim Limit/Sender, what do you think about this option?:

https://www.youtube.com/watch?v=Q70Fc2gWgZQ

 

[achris]

...What about opening the Trim Limit Switch and cleaning the connections and adding dielectric grease?

You can try it, but the success rate is about 40%... and even then, not long-term...

 

[BlueNote2]

achris,
I believe you, but if the wires are good, why couldn't a person just splice new TL puck to old wires?
Just curious, as I cannot afford to have that one fixed at shop right now.

Did you say I could temporarily use the Trailer switch to trim-up as needed?

 

[BlueNote2]

Remove the wires that go into the harness from the trim limit switch ('h' in the wiring diagram) and join the harness with a short length of wire.

HTH,

Chris........

where is the harness? This is a little confusing for me.

 

[achris]

.I believe you, but if the wires are good, why couldn't a person just splice new TL puck to old wires?
Just curious, as I cannot afford to have that one fixed at shop right now.

This discussion was had a long time ago, and was debated on this forum quite heatedly.

You can't splice to the existing wires for a few reasons. Usually the wire has enough oxidation on it that it makes getting a good joint difficult, but mostly because as the drive swings left and right the wires need to flex, and a soldered joint will not. That leads to either more broken wires, or other, more critical damage by the stiff sections of wire, or both.

Did you say I could temporarily use the Trailer switch to trim-up as needed?

Yes, but most people find that just plain annoying, and leave the short jumper in the harness so they can use the UP button for trimming. Being aware the UP can take the drive all the way UP....

 

[BlueNote2]

achris,
Thank you for great explanations and taking some time.

Yes, but most people... leave the short jumper in the harness so they can use the UP button for trimming. Being aware the UP can take the drive all the way UP....

oh, okay! So the jumper is a workaround (I'm a little dense sometimes).
However, I still don't understand which wires to connect and what/where the harness is. Anyway of being more specific, or perhaps point me to an existing thread that might have this info?

 

[achris]

where is the harness? This is a little confusing for me.

Sorry, missed this one earlier...

The harness is the trim pump harness. If you look at the trim pump you should see the mass (or mess) of wiring around it. In that lot you find the wires shown in ADs posted wiring diagram.... You're looking for the 2 black wires that plug into bullet connectors on the blue wire and on the purple wire.

 

[JaCrispy]

where is the harness? This is a little confusing for me.

I just did all this stuff to my boat. For clarity, the trim switch is on the control of the boat, the limit switch is the "puck" on the port side of the drive. You don't need to worry about the sender (stbd side of drive), that only works the gauge on the dash.

To find the wires for the limit switch, at the pump, trace the harness with the 3 prong connector (black, round cylindrical plug). At some point close to the pump you should see a single connector with 2 blue wires on one side and one on the other, next to it just a single purple wire and connector. See red circle bottom left side of wiring diagram. Unplug those wires and connect the purple with the 2-blue connector. That will bypass the limit switch.

 

[JaCrispy]

I forgot I had a pic.

The top arrow points to the 3 prong connector. The bottom arrow is the limit switch connectors. Yours should be similar but maybe not in the same exact spot, so trace the harness back a little until you find the 2 blue wire connector.

 

[BlueNote2]

Thanks!!

 

[BlueNote2]

anybody know where the Trim Pump is on a 1986 470?!

I cannot find it!

 

[JaCrispy]

anybody know where the Trim Pump is on a 1986 470?!

I cannot find it!

Push the trim button and listen for the buzz.