Johnson 50HP Hydro-Electric shift diode question

[dicktaber]

Hi--I have a 1972 Johnson 50HP with the Hydro-electric shift. It works great but on engine shutdown the lower unit "thunks" into forward. The book says that the shift diode (aka "monkey balls") is done. I don't want to pay OMC/Bombardier $70+ for this thing. It appears to be two diodes in series? parallel? (three wires) but since they currently read "open" in all directions I can't figure out the original current flow direction. The purpose is to maintain current to the neutral solenoid for that one second after ignition is turned off. I can buy diodes from Radio Shack and wire them in if someone can tell me which one goes in what direction...or if you have one that works and don't mind putting an ohmmeter to it and tell me which wires have continuity and which show open, I'd really appreciate it!

 

[Dhadley]

Re: Johnson 50HP Hydro-Electric shift diode question

From a safety standpoint -- spend the bucks. Especially if you run the motor on the hose with the prop on. Not a good idea but a lot of people do.<br /><br />Good luck!

 

[petryshyn]

Re: Johnson 50HP Hydro-Electric shift diode question

if you're a hobbyist, and can supply a schematic of the shift switch selector, I can help. But as Dhadley suggests, if it hinders safety, forget it!!

 

[Dhadley]

Re: Johnson 50HP Hydro-Electric shift diode question

The diodes aren't part of the shift switch. They are part of the stator circuit to keep it in neutral when the ignition is shut off.<br /><br />Good luck!

 

[petryshyn]

Re: Johnson 50HP Hydro-Electric shift diode question

Hi Dhadley!!<br />As far as I can detect, they supply voltage to the N solenoid until engine finally quits. The schematic I have doesn't show the switch, so I can only guess that the switch must connect the diode assmy.output to the neutral solenoid. Gotta see how its hooked before I reverse engineer the diode block. I'll bet they are simply two cathode connected together and the anodes to the charge coil, but I aint guessing from this distance!!!!!!! <br /><br />Take care!!<br />

 

[dicktaber]

Re: Johnson 50HP Hydro-Electric shift diode question

Dhadley you are correct--it is a seperate component that receives power from the stator as long as there is output; when you turn off the ignition switch, battery power is no longer available, then the diode prevent the reverse current and keeps neutral engaged. My current practise is to put it into forward (boat tied up at the dock) then turn off the key; this prevents the clunk. <br /><br />Schematic--if you send me an fax number I can send a wiring diagram. Can't figure out how to update my profile, and the censor doesn't like my email address so I'll encode and you can decode. d/i/c/k_taber@hotmail.com--to decode, remove the /'s. Thanks for all your help; it's not a safety issue, more of a lower unit undue wear issue...

 

[petryshyn]

Re: Johnson 50HP Hydro-Electric shift diode question

Hey...Knot2much:<br /><br />can you scan and send it to my e-mail? If not I'll email you my fax....let me know...<br /><br />schematic2@yahoo.ca