Switch ID in transom 165 Merc/MC1

[sextondm]

Hello all;
Boat in question is a '76 Starcraft, 165 Merc i/o and MC1 Drive (Ser. 3647773). If I'm looking in the right place, I believe the trim switch and trim sender are removed from my drive?
I think the wires should be connected at the bullet connectors that are connected to either side of the bellhousing in black plastic pieces, but there are no wires going into them from the drive, and I do not see any switches on the drive.
My drive does tilt up/down, and I have the regular three button setup and tilt/trim gauge as well. Gauge appears to not be functioning properly, which I would guess would coincide with missing tilt limit switch and sender??
I rebuilt the dash and had to re wire most of the existing wiring, as it had all been cobbled together over the years. Before I did the dash/wiring, my trim gauge seemed to work. Now it doesn't, and that started me going through wiring/switches.
On the trim gauge, I have one red wire coming from the transom to the "sender" terminal, a white wire on the "IGN" terminal that goes to the Ign. terminal of the Ign. switch and a ground and a light.
I'm no expert on boats, and this one is my first, so if I'm totally off on what I'm looking at please steer me in the right direction!
Thanks!
Here are pictures of what I've got...

 

[sextondm]

Switch ID in transom 165 Merc/MC1

Ok guys,
I am really trying to learn my boat. I am in the process of rewiring the dash and all the gauges/switches on the instr. panel.
Having issues with tilt/trim gauge, and I'm trying to ID some of the switches in the transom so I know what I'm looking at.
I know one of these is shift linkage with I'm guessing the neutral safety switch or switches? There are two switches where the shift linkage attaches in the transom.
The other one, is above the shift linkage/off to the side and mounted to the transom.
There are also two black plastic square blocks, with two wires going into each, and none coming out, mounted on either side of the bellhousing. One has 1 black wire and 1 brown wire, the other 1 purple/white and 1 black. They look like female bullet connectors, that are held in place by the black blocks and screwed to the bellhousing. But, there are no wires going to them? What gives?
Thanks, and forgive the novice questions...

 

[Bondo]

Re: Merc 165 Tilt/Trim Questions/Help!

Re: Merc 165 Tilt/Trim Questions/Help!

Ayuh,.... That drive is so Old, it don't have the sender/ switch....

On the transom is the reverse lock/ gauge sender...
It's plumbed in-line with the return oil line of the trim/ tilt....

 

[sextondm]

Re: Merc 165 Tilt/Trim Questions/Help!

Re: Merc 165 Tilt/Trim Questions/Help!

Thanks Bond-o.
My second post there was not supposed to be a "reply" to my first. Don't know how that happened. It was supposed to be a separate post.
At any rate, how does the drive know where it's at for the sender signal, and how does it know it's in reverse?
My drive goes up and down fine, but the gauge isn't reading/moving with the drive. I traced the wires coming off of the gauge. One goes to 12v Ign. post on the ignition switch, the other to the transom to what you said is the reverse lock/trim sender, and then to ground. The gauge also has a ground, and a power to the light socket.

 

[Don S]

Re: Merc 165 Tilt/Trim Questions/Help!

Re: Merc 165 Tilt/Trim Questions/Help!

You really shouldn't post the same questions in two different forums. Bondo moved one of your treads from the Electical forum to here, then merged the two together since it's all about the same thing.

Best bet you could do now is look in the oem service manual and do some reading to understand shift and trim systems and how they work together. http://boatinfo.no/lib/mercruiser/manuals/mercruiser2.html#/0

This explains your trim sender http://boatinfo.no/lib/mercruiser/manuals/mercruiser2.html#/544

The neutral safety switch is in the throttle/shifter control, and you have a reverse lockout on the drive.