Short story: I need help diagnosing why my trim won't operate with a new control box on an older outboard.
Long story: I've got a c.1984 Mercury 115 tower of power with the original Quicksilver control. Boat is a late 80's 17' bowrider. Had to replace the control box and had to upgrade to a Mercury 4000 SMC box. The original box had the 4 wire trim bundle leaving the box completely separately from the 8 pin control harness. Then a few feet from the outboard, the 4 wires changed over to a 3 prong plug, etc. Then after the plug, a new trim harness began and ran all the way to the trim solenoids.
The new box has the trim wire embedded in the harness all the way to end then 4 wires emerge next to the 8 pin motor control end. The 4 wires are blue, green, and brown with male bullet connector ends. The fourth wire is tan with a female bullet end. I tried using the old original trim wire out of the old Quicksilver box and putting corresponding bullet ends on it then keeping the plug assembly in place with my new "reverse harness" plugging to the new ends next to 8 pin plug then running back out to the 3 prong plug. The Solenoids clicked when up or down is pushed in each direction but no action of actually making the trim motor actually engage.
I then went and cut through the old harness coming from the solenoids (left myself plenty of wire to play with) to try to connect directly with the new harness. The old harness was three wires: green, blue, red. Blue for the up solenoid, green for down and red for hot. I have some alligator clip leads to test with. My guess was the brown or the tan that one was hot and one was a ground. I connected green to green and blue to blue. Then I tried each of the other two on the new harness (brown and tan) alternatively with one to red and the other grounded. Also tried each one separately to red with no ground. All results were the same: solenoids remained clicking strongly but no other action.
Other possibly relevant details:
8 pin motor control part is working fine. Motor fires up and runs well in both forward and reverse. I tested it with a garden hose and "ears."
The trim is either fully down or nearly fully down. I cannot examine anything with the trim motor or pump at this point. If I need to, then I need a pointer on how to tilt the motor up manually.
I have checked the inline fuse connected to the trim solenoids. It is good.
The motor control was replaced due to the ignition switch breaking then I messed it up trying to repair the switch. Totally separate story which led me to purchasing the new unit. Besides, I want to get this boat in reliable enough condition that my 21 year old daughter or 17 year old son can take it out on their own without me worrying about its reliability.
Before the motor control being replaced, there was an issue with the trim, particularly when raising (going up). Sometimes the trim would engage the first time you mashed the switch, sometimes it took as many as 4 or 5 times before it would engage. As now, the solenoids would click but no action, and as I said it was much more of an issue in moving up than down. But now, no matter how many times the up or down switch is pushed or how long it is held, there is no engaging in either direction.
Thanks in advance for any help! I live in an isolated small town. The only nearby marine repair shop is 6 weeks out on work and I'd really like to get on the water a lot sooner than August.
Long story: I've got a c.1984 Mercury 115 tower of power with the original Quicksilver control. Boat is a late 80's 17' bowrider. Had to replace the control box and had to upgrade to a Mercury 4000 SMC box. The original box had the 4 wire trim bundle leaving the box completely separately from the 8 pin control harness. Then a few feet from the outboard, the 4 wires changed over to a 3 prong plug, etc. Then after the plug, a new trim harness began and ran all the way to the trim solenoids.
The new box has the trim wire embedded in the harness all the way to end then 4 wires emerge next to the 8 pin motor control end. The 4 wires are blue, green, and brown with male bullet connector ends. The fourth wire is tan with a female bullet end. I tried using the old original trim wire out of the old Quicksilver box and putting corresponding bullet ends on it then keeping the plug assembly in place with my new "reverse harness" plugging to the new ends next to 8 pin plug then running back out to the 3 prong plug. The Solenoids clicked when up or down is pushed in each direction but no action of actually making the trim motor actually engage.
I then went and cut through the old harness coming from the solenoids (left myself plenty of wire to play with) to try to connect directly with the new harness. The old harness was three wires: green, blue, red. Blue for the up solenoid, green for down and red for hot. I have some alligator clip leads to test with. My guess was the brown or the tan that one was hot and one was a ground. I connected green to green and blue to blue. Then I tried each of the other two on the new harness (brown and tan) alternatively with one to red and the other grounded. Also tried each one separately to red with no ground. All results were the same: solenoids remained clicking strongly but no other action.
Other possibly relevant details:
8 pin motor control part is working fine. Motor fires up and runs well in both forward and reverse. I tested it with a garden hose and "ears."
The trim is either fully down or nearly fully down. I cannot examine anything with the trim motor or pump at this point. If I need to, then I need a pointer on how to tilt the motor up manually.
I have checked the inline fuse connected to the trim solenoids. It is good.
The motor control was replaced due to the ignition switch breaking then I messed it up trying to repair the switch. Totally separate story which led me to purchasing the new unit. Besides, I want to get this boat in reliable enough condition that my 21 year old daughter or 17 year old son can take it out on their own without me worrying about its reliability.
Before the motor control being replaced, there was an issue with the trim, particularly when raising (going up). Sometimes the trim would engage the first time you mashed the switch, sometimes it took as many as 4 or 5 times before it would engage. As now, the solenoids would click but no action, and as I said it was much more of an issue in moving up than down. But now, no matter how many times the up or down switch is pushed or how long it is held, there is no engaging in either direction.
Thanks in advance for any help! I live in an isolated small town. The only nearby marine repair shop is 6 weeks out on work and I'd really like to get on the water a lot sooner than August.
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