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huntingtheworld

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alot on here and never get and answers.can someone help me with this.i have a 1972 johnson powershifter ii 65 hp and it does not go in reverse and i was told to check the dioads and umm they are missing.where are they supposto go.and also does any one have a brakedown of the lower unit or something that will help me.and also do iboats have a good manual i need a service malual for it.thanks jason
 

Daviet

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Re: i post

You did not list your model#, so I could not look up your exact motor. You should have a shift switch in the control box and shift solenoids in the lower unit.
Get a factory manual from Ken Cook, it will have troubleshooting and parts breakdowns for your motor.
You can go to the Johnson webite, punch in your model# and get a parts breakdown for your motor.
 

huntingtheworld

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Re: i post

the switch is good and the solenoids are good too.i am just wondering about the diodes couse they are missing i think someone cut then off.model 65esl72s
 

Daviet

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By looking at the parts breakdown for your engine I don't see any diode in the shift circut, unless it is part of a harness and is not available as a seperate part. If your shift switch and shift solenoids are working properly I would wounder if your problem is in the pump in the lower unit that supplies pressure to shift the lower unit.
 

huntingtheworld

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Re: i post

to be honest i don't even know where the pump is and i Reilly didn't see one.i ant to good with lower units only the motor part lol.
 

Daviet

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The pump as well as the shift solenoids are in the lower unit. How did you test the shift switch and shift solenoids?
 

huntingtheworld

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Re: i post

my dad did all that he is a electrician.i did not watch him but it had 6 oms.and the switch he used a meter i think and he said it was good
 

tashasdaddy

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Re: i post

huntingtheworld , 1st many people do not know anything about those motors, and the ones that do, are much older.

(J. Reeves)

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.

You CAN NOT use HI VIS lube in that lower unit. You MUST USE what OMC calls "Premium Blend" lube, commonly called "Type C". (A thinner lube)

Note: The engine must be running OR have the driveshaft turning by some other means in order for the engine to shift.

In neutral, you need 12v to the "Green" wire.
In reverse, you need 12v to both wires, the "Green" one and the "Blue" one.
In forward, there should be no voltage to either wire. (The spring loaded shifter dog forces the unit into forward gear)

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.

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).
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.
 

ezeke

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Re: i post

Click the thumbnail twice - it's as clear as I can get at this resolution. If you save it and enlarge it, you should be able to read it.
 

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eavega

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Re: i post

Jason

Make sure you have the lower unit full of oil. These motors shift by forcing that oil through different passages, thus by hydraulic pressure. If there is nothing but air to push, the engine won't shift.

-E
 

eavega

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huntingtheworld , 1st many people do not know anything about those motors, and the ones that do, are much older.

Hey, I resent that! Some of us aren't "much older" (40 ain't all that old), but we have learned some of the ways of these of these older motors :D

-E
 

F_R

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Re: i post

the switch is good and the solenoids are good too.i am just wondering about the diodes couse they are missing i think someone cut then off.model 65esl72s

If you are looking for a "blocking diode" in the control, there is none on that motor. If you are looking for the shift diodes on the motor, they are a pair of "monkey nutz" connected to the terminal strip---yellow wires.
 

huntingtheworld

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Re: i post

the lower unit has type c oil and all i was told was to find the diodes and check them cause thats about the only thing left.i have checked about everything thair is to check.
 

F_R

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Re: i post

alot on here and never get and answers.can someone help me with this.i have a 1972 johnson powershifter ii 65 hp and it does not go in reverse and i was told to check the dioads and umm they are missing.where are they supposto go.and also does any one have a brakedown of the lower unit or something that will help me.and also do iboats have a good manual i need a service malual for it.thanks jason

Um, are we confused here? The 1972 motor has Hydro-Electric Shifting. Powershift II came out in 1973 and is a hydraulically assisted mechanical shift, a totally different system. The controls are not compatable. So exactly what are we dealing with here???
 

huntingtheworld

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Re: i post

i may be hell lol i relllay dont have a clue about this thing.i gave you the model number what ever that says it is it is.all i know is it ant going into reverse and have checked almost everything.thanks jason
 

ezeke

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Re: i post

That's the model number for your 1972 motor but the Powershift remote control won't operate it.
 

huntingtheworld

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Re: i post

it has a push button forword and neturel and reverse.when u push reverse it barly speens.if thats what ur asking
 
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