tilt/trim stupid question

simplydave

Seaman
Joined
Jun 21, 2014
Messages
59
I have that 88 100hp mariner 4 cylinder and the t/t doesn't work. I have tried to bypass the solenoids and relays by connecting a positive lead from the battery to the blue wire or green wire and connecting the other to ground. All I get is spark which to me indicates a dead short. Ok so far? Looking at the motor, I cannot locate an up or down solenoid. On the starboard side of the motor is the starter and its solenoid and the two relays and the wiring block. Can anyone tell me where the up/down solenoids are located at?
 

sam am I

Commander
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Jun 26, 2013
Messages
2,169
I have tried to bypass the solenoids and relays by connecting a positive lead from the battery to the blue wire or green wire and connecting the other to ground.

Where exactly were these "blue and green wires" located that you were connecting the battery positive too?
 
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simplydave

Seaman
Joined
Jun 21, 2014
Messages
59
they are the wires that come out of the relays on the starboard side of the motor. I've tried connecting a jumper lead between terminals 87a and 30 and 87 and 30 but the jumper wire just heats up before any movement is made by the tilt motor.

The reason I'm doing that is I found a procedure called Troubleshooting, testing and bypassing the SPDT Power trim tilt relays on the web and thought I'd try it.

While examining the trim motor, I see only one allen head bolt on the port rear quarter, is there another on the starboard front quarter that's not visible? The manual I bought does not show this outboard model in any type of detail. It's like everything about it is a secret.
 

sam am I

Commander
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Jun 26, 2013
Messages
2,169
Ahhhh, well you must first dis-connect the wire from the #30's relay post before you can hook it to 12V.

So for example bypassing the up relay and to make the trim go up........The blue wire that runs down to the motor that is also connected to one of the relay's #30 post must be removed from the relay, THEN you may touch the blue wire to 12V. You do this while leaving the opposite relay (the grounding relay) with the green wire alone and/or jump its #30 post to ground.

To reverse the motor to go down, you do the same as described above only use the green wire.

Or, just take both blue and green wires off the relay's #30's and proceed accordingly.

The reason is that both relay's #87a paths are hard wired to ground and while at rest, the relay's #30 is internally connected to #87a. This is why #30 is arcing when you jumper it to 12V.(see image below)

You have a 2 wire motor, check out post #4 and #7 at the link below, it might help answer a few mysteries......GL and not a stupid question BTW, this confuses a lot of people!!


http://forums.iboats.com/forum/boat-...s-or-solenoids


lable 2 wire H bridge.jpg
 
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