1969 55 hp johnson hydro electric shift

bill7463

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Jun 18, 2003
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i have a 1969 55 hp johnson hydro electric shift and i am having some problems with it. when i engage the throttle forward it goes forward, when i engage the throttle into reverse it goes forward, and when i am in neutral it is still moving forward slowly can any one help me
 

Joe Reeves

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Feb 24, 2002
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Re: 1969 55 hp johnson hydro electric shift

Bill.... The following explains the shift setup of your engine.<br /><br />(Hydro Electric Shift)<br /><br />The shifting setup of the lower unit is what's called a "Hydro Electric Shift", which is quite complex consisting of voltage being applied to solenoids in the lower unit which in turn change oil passages via a oil pump that supplies various pressure on a spring loaded shifter dog. The wires leading to the lower unit (at the powerhead) are "Green" and "Blue". The engine must be running or cranking over in order to shift out of forward gear.<br /> <br />You CAN NOT use HI VIS lube in that lower unit. You MUST USE what OMC calls "Preminum Blend" lube, commonly called "Type C". (A thinner lube) <br /><br />In neutral, you need 12v to the "Green" wire. <br />In reverse, you need 12v to both wires, the "Green" one and the "Blue" one. <br />In forward, there should be no voltage to either wire. (The spring loaded shifter dog forces the unit into forward gear) <br /><br />To check the lower unit for proper shifting to make sure you have no trouble there, remove the spark plugs to avoid problems and to allow a higher cranking speed. <br /><br />This next step eliminates the actual shift switch in case problems may exist there.... Disconnect the blue & green wires at the knife connectors (the rubber insulated boots) leading to the lower unit at the powerhead, then using jumpers, take voltage direct from the starter solenoid to apply voltage to the "Green" wire for neutral, then both wires 'Green" & "Blue" for reverse (Remember the engine must be cranking over in order to shift).<br /> <br />With no voltage applied, the unit should be in forward. No need for a ground jumper... the lower unit's already grounded. You may crank the engine with the key switch or by energizing the starter solenoid with a jumper wire.
 

bill7463

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Re: 1969 55 hp johnson hydro electric shift

thanks for the response<br />I tore the lower unit apart and i think i found my problem. the plunger rod was broke off right where it screws into the small nut. Do you have any ideas where i can get one of these at or is there a way i can fix mine.
 

Joe Reeves

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Feb 24, 2002
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13,262
Re: 1969 55 hp johnson hydro electric shift

Bill.... I don't know how you could fix yours, and I don't have that plunger in stock. However I do have the complete replacement kit assy (new). It consists of the solenoids, plunger, cable, cover cap, etc etc. If you can't locate just the plunger, contact me at ReevesJ32@aol.com
 

Brandon31386

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Jun 22, 2010
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Re: 1969 55 hp johnson hydro electric shift

Could bad gear oil be a problem? I'm having this same issue with my johnson. I dont think the LU oil has ever been changed. I'm hoping that when I put new stuff in I'll have neutral and reverse back.

Is taking off the LU a difficult job?

Thanks!
 

bigpoppakdog

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Jul 9, 2008
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Re: 1969 55 hp johnson hydro electric shift

ah, your going to get dinged for hijacking someone's thread. maybe start your own.
 

Brandon31386

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Jun 22, 2010
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Re: 1969 55 hp johnson hydro electric shift

I'm sorry. I figured why spam the forum with the same exact issue someone else was having. :D
 
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