Trim control question on 3.0 Alpha

[rgf1046]

I have a '91 Larson 17' w/ the 3.0 Mercruiser Alpha 1 drive. Question is, the trim switch on the Quicksilver control works to trim down, but not up. The trailer button, however, works fine to raise the outdrive. I can't hear the pump engage at all when I activate the trim switch up. Is it possible that it's a contact in the switch itself, or would it have something to do with a sending unit on the drive? Any help is appreciated, thanks.

 

[Bondo]

Re: Trim control question on 3.0 Alpha

or would it have something to do with a sending unit on the drive?

Ayuh,.... That's the very 1st place to look....

 

[rgf1046]

Re: Trim control question on 3.0 Alpha

Any suggestions on how to troubleshoot a sending unit, or how to determine which one is at fault?

 

[Chris1956]

Re: Trim control question on 3.0 Alpha

The trim limit switch is located on the outdrive, where the OD pivots as it trims. One side is the trim gauge sender, the other is the trim limit switch. If you remove he two stainless steel phillips screws, you will expose the guts of the trim limit switch. If there is anything left, you can clean or replace parts.

Another idea is to bypass the trim limit switch. There are two bullet connectors in the trim wiring harness near the trim pump. Unplug the trim limit switch leads and connect them together. They should be purple wires.

 

[Don S]

Re: Trim control question on 3.0 Alpha

Click on the link below to the Service manual for the Alpha I, then download section 1C. Complete details on how to check your system.

http://www-alt.mercurymarine.com/mnetdata/SERVICE/CRUISER/Servmanl/6/6covr3.pdf

 

[rgf1046]

Re: Trim control question on 3.0 Alpha

Great, thanks for the direction, I'll see if I can get it from here. Much appreciated.

 

[rgf1046]

Re: Trim control question on 3.0 Alpha

Ayuh,.... That's the very 1st place to look....

That was it, one of the leads had broken off the T/L switch. Thanks for the help!