1966 650 tilt/trim limit switch wiring. Test your knowledge here please comment!!!

[iamwill1973]

Ok a 650 mercury I removed from the v178 starflite and installed on a 15' 1970 model glastron has some electrical wiring issues I have to repair nothing serious under the cowl. I also noticed the wiring from the tilt motor to the limit switches beside the starboard side ram on the actual business end of the system is rotted and broke in several places. I saw this unit work a couple times before doing the repower, so I am at a loss with this I do not understand how it works without being hooked up to the limit switches. I have the manual found here http://www.scribd.com/doc/75281168/Mercury-Outboard-Tilt-Manual and I still do not know if it needs to be rewired or not. Could someone please comment advise or just tell your knowledge on this situation? Please!!! Looks like I will have to remove a piston ram to get to the switch box it is mounted in. The cable is extremely rotted but it looks like it only had one wire in it but it should be 2?

 

[iamwill1973]

Re: 1966 650 tilt/trim limit switch wiring. Test your knowledge here please comment!!

Bump any ideas at all is cool

 

[Texasmark]

Re: 1966 650 tilt/trim limit switch wiring. Test your knowledge here please comment!!

Basic theory is that you have two high current switches or solenoids. Some may look similar to the starting solenoid. Larger wires will go to them along with smaller control wires. A red wire from fused battery power goes to the center position of your trim switch carrying 12v as long as the battery is connected to the engine. The "rocker" switch is a momentary ON, single pole double throw....one circuit that can be directed in either direction.

The power is applied to a blue or green wire, and can be a blue/white stripe, or green/white stripe and these wires go to the control windings of the up/down solenoids.....small terminal. Either internally or externally the solenoids use a black wire to connect to the battery neg terminal....may go to the engine block which is at battery neg.

Moving the rocker switch in the desired direction will put 12v onto the trim pump motor and cause it to run the piston out or in depending on which relay gets the voltage. That's it.

Mark

 

[Chris1956]

Re: 1966 650 tilt/trim limit switch wiring. Test your knowledge here please comment!!

Will, If the PTT system is wired the same as my '77 Merc was, it will have had a three pushbutton PTT panel. The middle button was for trim up and required that the trim limit switch was closed. Pushing middle and top buttons together bypassed the trim limit switch and caused the motor to tilt up. Obviously the lower button was for down.

The trim limit switches did have two wires. Lt blue and Purple if memory serves. Jumper the trim limit wire connections in the main harness to bypass it. Some Merc PTT systems had 2 solenoids, some only 1 solenoid.

If it were me, I would bypass the trim limit switch.

 

[Texasmark]

Re: 1966 650 tilt/trim limit switch wiring. Test your knowledge here please comment!!

Will, If the PTT system is wired the same as my '77 Merc was, it will have had a three pushbutton PTT panel. The middle button was for trim up and required that the trim limit switch was closed. Pushing middle and top buttons together bypassed the trim limit switch and caused the motor to tilt up. Obviously the lower button was for down.

The trim limit switches did have two wires. Lt blue and Purple if memory serves. Jumper the trim limit wire connections in the main harness to bypass it. Some Merc PTT systems had 2 solenoids, some only 1 solenoid.

If it were me, I would bypass the trim limit switch.

Thanks Chris. I was reading out of my Commander 2000/3000 wiring diagram. Guess they weren't available back then.

Mark

 

[iamwill1973]

Re: 1966 650 tilt/trim limit switch wiring. Test your knowledge here please comment!!

So Chris if I understand you correctly it is ok and will allow the tilt/trim to operate if I just do not hook the limit switch up at all? The wiring that comes from the switch on the transom is extremely rotten and just crumbles I can only make out one rusty wire though it looked like 2 wires were originally hooked up there. Also it apopears if I do want to redo it I will have to remove one piston ram? to get to the switch box I cannot really tell what that even entails. I am going to plug the holes in the transom from the previous motor and hopefully work on putting the throttle cables back on, worried about that because I took out the shift cable and the bolt it was hooked to slipped forward after removing the cable. After confirming proper operation with a crank and idle test I want to replace wiring on the tilt motor and clean it up good then change the oil out because it looks really OLD. would like it if I just did not have to worry about the limit switch at all. Would I have to jumper a wire from it to something else if I do not hook it back up I guess is my next question sorry for rambling. Oh yeah and chris there was a simple rocker switch hooked to it actually said johnson on it lol up and down pretty simple no trailer. It had a common battery hot and a blue and green hooked up to I guess green for grass down and blue for sky up. I know I used to have a celebrity bowrider and when the tilt messed up I just bypassed that just do not remember how I did it something like I used the trailer function to go up down worked fine.

 

[Chris1956]

Re: 1966 650 tilt/trim limit switch wiring. Test your knowledge here please comment!!

Yes, just jumper the trim limit switch. Blue is up, green is down. Black is ground. The PTT units normally use 5W-30 motor oil, but some folks use ATF instead. Pick one and don't mix them.