1972 johnsom hydro electric lower unit

i bought a used lower unit from a boat shop and installed it it goes into gear when i put the water ears on it but when i put it in the water nothing happens i checked the prop hub to make sure i didnt spin it ive already sunk about 600 into it any ideas ? and can i change it over to a mechanical shift lower unit ?

Re: 1972 johnsom hydro electric lower unit

No, you can't convert to a manual shift. Are you sure it's actually in gear on the muffs, or just turning the prop by momentum. Try turning the prop with the engine not running and the key off, it should be in forward, be CAREFUL, engine could possiably start if all the stars are aligned. Remove the plug wires from the plugs just to be safe.

Re: 1972 johnsom hydro electric lower unit

i just tried that and it turns the motor when i turn the prop forward and it makes a weired clicking noise in reverse ive bought 3 sets of silonoids for it backed it of in my pond still nothing even unplugged the silinoids to see about forward and nothing. if the power head didnt crank every time the key turned id get rid of it but its hard to find parts for it anywhere so any advice is greatly appreciated thanks

Re: 1972 johnsom hydro electric lower unit

So you bought a used lower unit and installed it and you have no forward even with both blue and green wires disconnected?
If that is true, and you have the correct lower unit fluid (type C) in and it's full, then the lower unit is bad. If no voltage is going to the lower unit whatsoever, it should be in forward.
The only other thing I can think of, is that the hub in your prop is badly slipping. If the motor is turning the prop on the muffs, and not in the water, that's what I'd think the problem is. IF the prop hub is bad enough, even the friction of the water on the prop is enough to cause it to slip since the torque on the prop shaft is pretty darned high.
I would think you could remove the prop, and see if the lower unit is shifting properly on the muffs---going from forward to neutral, then neutral to reverse. If it will do that, then the prop hub is probably bad. Have you changed out solenoids on the "new" lower unit or just your old one?

Re: 1972 johnsom hydro electric lower unit

yes i have replaced the silinoids in the other lower unit we just got back in from trying the prop off it has the type c oil in it i dont know wish i could just sell the darn thing and get me something that i can take to the shop and have fixed no one around here even wants to talk about workin on the old motor
but i dont know it acts like its hung up in between revers and forward thought about trying to find another lower unit but a little gun shy

Re: 1972 johnsom hydro electric lower unit

Is the oil in the lower unit clean? It might be worth trying to flush the lower unit. Drain the oil and fill with ATF and run it on the hose and see if it starts to shift properly. If so, shift it several times and then drain the ATF out and fill it with the proper oil, Type C.

Re: 1972 johnsom hydro electric lower unit

If you just replaced the solenoids in the g/c you have, and had the plungers out,
are they adjusted correctly??

Re: 1972 johnsom hydro electric lower unit

ennis 2 said:

i just tried that and it turns the motor when i turn the prop forward and it makes a weired clicking noise in reverse ive bought 3 sets of silonoids for it backed it of in my pond still nothing even unplugged the silinoids to see about forward and nothing. if the power head didnt crank every time the key turned id get rid of it but its hard to find parts for it anywhere so any advice is greatly appreciated thanks

Click to expand...

I'm not sure if I understand. Are you saying in the first bold statement that you've rebuilt this lower unit 3 times with 3 different sets of solenoids? If the lower unit is put together correctly with a good clutch dog and gear ears, I'd think it would be in forward before you even cranked it due to the spring that puts pressure on the clutch dog. With no voltage to the green or blue wires, it should remain in forward during and after cranking since only voltage on the solenoid will allow oil pressure to disengage the clutch dog (if the solenoid plunger is adjusted properly). Even if the oil pump went out and the solenoids were bad, I'd think it would be in forward.
See: http://forums.iboats.com/showthread.php?t=326486&highlight=hydroelectric+shift+test

Your lower unit is either not put together properly or missing or bad parts-- or it would be in forward.
I hope the link is more helpful.
Here's another to show a diagram of the lower unit: http://www.crowleymarine.com/johnson-evinrude/parts/42720.cfm
I'm thinking that the solenoid shaft may be out of adjustment as a previous poster mentioned, but I would think you would have at least seen it in forward for a moment when you cranked it on the muffs before it built up oil pressure.
Good luck,
JBJ

Re: 1972 johnsom hydro electric lower unit

no its a lower unit that was takin off a locked up motor no mechanic around houston will touch this lower unit i know nothing about this lower unit but everybody says they r a pain how do u adjust the plungers ? wen i bought the boat the original lower was locked up so i bought this used one id rather put it in the shop but no one will work on it the power head is awesome for its age fires up every turn of the key is the only reason im goin to this extreme to fix it

Re: 1972 johnsom hydro electric lower unit

I think you need to get a factory manual for your engine. It will have all the specs and procedures to check out your engine. You can try e-bay or google Ken Cook, he has duplicate manuals. Make sure that you get your manual by using your model number to get the correct manual.