1972 50hp Johnson

[Tinker Mark]

My motor worked fine, until I replaced the H2O pump. The motor won't go into reverse now & once shutdown it won't restart because the 20amp fuse is blown. If I replace the fuse it will start again but still not shift into neutral or reverse once shifted into forward. I tested the shift solenoids & both tested @ 5-6 Ohms, any suggestions?

 

[racerone]

Re: 1972 50hp Johnson

Did shift wires get pinched when you re-installed the lower unit ?---------Pull it apart again.------Hook battery - to casing and apply 12 volts + to both green and blue.---------Motor should shift to reverse after about 2 turns of the driveshaft.------Use a vicegrip to turn the driveshaft.

 

[Tinker Mark]

Re: 1972 50hp Johnson

Did shift wires get pinched when you re-installed the lower unit ?---------Pull it apart again.------Hook battery - to casing and apply 12 volts + to both green and blue.---------Motor should shift to reverse after about 2 turns of the driveshaft.------Use a vicegrip to turn the driveshaft.

I dropped the lower drive & the wires appear intact. However could there be a brake in the insulation I'm not seeing that allows water to short out 1 or both wires when in the water? If so can I change just the solenoid harness?

 

[Tinker Mark]

Re: 1972 50hp Johnson

My motor worked fine, until I replaced the H2O pump. The motor won't go into reverse now & once shutdown it won't restart because the 20amp fuse is blown. If I replace the fuse it will start again but still not shift into neutral or reverse once shifted into forward. I tested the shift solenoids & both tested @ 5-6 Ohms, any suggestions?

I removed the lower drive & the wires appear intact, however could there be a break in the insulation of 1 or both wires I'm not seeing which allows to short the wire(s) when in the water? If so can I change just the wire harness for the solenoids?

 

[racerone]

Re: 1972 50hp Johnson

Did you test as per post #2 -----????

 

[Joe Reeves]

Re: 1972 50hp Johnson

I assume that the problem did not exist prior to you removing the lower unit? If so, somehow you have created a short in the shift wires leading to the lower unit.... a wire shorting out to ground.

A break in a wire would not cause a fuse to blow... it would need to be a short.

 

[Tinker Mark]

Re: 1972 50hp Johnson

I removed the lower drive & the wires appear intact, however could there be a break in the insulation of 1 or both wires I'm not seeing which allows to short the wire(s) when in the water? If so can I change just the wire harness for the solenoids?

I will next time I can work on it. My post about removing the lower end was in regards to the first action I took when it didn't shift correctly. Also I will check the wiring that I might've disturbed during my initial re-work.
sorry for adding to your 1st post, I'm new to this forum thing. And thanks for the information.

 

[racerone]

Re: 1972 50hp Johnson

It shifts into forward gear when no power is applied to the solenoids, this is done by spring action.-----I would take the lower unit off agian , look at the wires and test it when it is off.

 

[Tinker Mark]

Re: 1972 50hp Johnson

I assume that the problem did not exist prior to you removing the lower unit? If so, somehow you have created a short in the shift wires leading to the lower unit.... a wire shorting out to ground.

A break in a wire would not cause a fuse to blow... it would need to be a short.

Yes a broken wire wouldn't blow a fuse or give me good Ohm readings. However a wire with broken insulation might go to ground when submerged, correct? So it looks like either way I have to drop the lower end & inspect the solenoid wires to eliminate that possibility before I move ahead. I can Also run Racerone's tests once I know the wires to the solenoids are intact. Thanks everybody for you willing & helpful advice.