1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

Charbonneau

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Lower unit electric shift stuck in forward tried everything can't find problem PLEASE HELP!....TY
 

JB

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Re: 1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

Hi, June.<br /><br />The HydroElectric shift engines go to forward when shifting power is lost. That's so you can get home if it fails offshore.<br /><br />You may have an electrical problem associated with your pushbutton panel, or you may have had a failure in the hydraulic pump circuit in the lower end that actually moves the clutch.<br /><br />You will need a manual and a voltmeter to troubleshoot the externals of the electrical circuit.<br /><br />If you have to troubleshoot the hydraulic circuit you will have to drop the lower end.<br /><br />Good luck and let us know what you find. :)
 

Charbonneau

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Re: 1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

TY for the input I hope it will work will give it a try again TY<br /> June Charbonneau
 

Joe Reeves

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Re: 1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

June.... The 1975 engines had no electric shift. Get the model number to us and we'll be able to pinpoint exactly what engine you have.<br /><br />However, should you have the "Hydro Electric Shift" type engine that existed in some models between 1968 and 1972, the following would pertain to your engine. I hope this is of some use to you.<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.
 

Charbonneau

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Re: 1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

Joe,<br /><br /> TY for the imput I will find out from by boyfriends father the serial # on the Johnson and get back to you on it your help is greatly appreciated again TY. <br /> June
 

Charbonneau

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Re: 1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

The serial # for the Johnson is JO527 if you can tell me the year as well as how to fix the problem it would be greatly appreciated......TY<br /><br /> June
 

Joe Reeves

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Re: 1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

June..... I've never heard of a serial number such as that. It's way too short a number. However, that's not what I said we needed. We need the "Model Number" not the serial number. Get that to us (The Model Number) and we'll see what we can do.
 

Charbonneau

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Re: 1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

sorry will try again will get model # for you misunderstood been sick for 2 weeks can't get rid of it. Again Sorry,<br /> June
 

Charbonneau

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Re: 1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

Model # for Johnson 65hp 3cyl. is 652735 sorry for the mess up.......TY
 

Joe Reeves

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Re: 1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

June.... That engine is a 1972 65hp Johnson with a "Hydro Electric" shift lower unit. Do the checks as per my previous post and let us know what you find.
 

Charbonneau

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Re: 1975 Johnson 65hp 3 cylinder problem elec. shift lower unit

TY for your help keep you posted as to what happens again..............TY.<br /><br /> June
 
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