1972 hydrostatic 125, hot wire blowing fuses.

starkizzle

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Hello, I have a 72 johnson 125- 125ESL72R
with the hydro static drive, first boat. I took it in trade and finally rebuilt the carbs and had it running, then the neutral safety switch went, along with the little short 20 amp glass fuse above the solenoid. After replacing the fuse, and then switch( I thought it was just the fuse, but fuse didn't start it, boat mechanic tested switch and i replaced it) and starting on muffs, i noticed that it stayed in gear when started. It would not go in neutral, and when i put it in reverse, the prop kept turning the same direction. After alittle research I found out about the hydrodrive johnson and how important the premium unit oil is. I used just regular stuff when I got it ready for the summer.. I drained the old stuff and replaced with new, correct oil. I started it, and it seemed like it may have been in neutral, and when I put it in reverse, it looked it was going to reverse direction ( the prop) but it died, and blew another fuse.
At this point I decided the look into the fuse more, I had already checked the lines from solenoid to the battery, and ignition system back to solenoid, before I found the bad fuse.. did not see anything grounding out. Where the 20amp was looked alittle frayed where it was bent back, so I replaced it with a new inline blade type and cut out the bad connection. I started up the boat and it remained in forward gear. The fuse did not blow, part i think because its 30a instead of the 20a but while checking the blue and green wire going to the lower for power ( and not being able to get a good number, bouncing all over the place, i noticed that green wire was getting hot.
So I know that with these hydro drive types you are suppose to get certain readings from certain wires in F/N/R, and i clearly have some sort of short, I am cutting into the wiring harness in the morning, checking that green wire around and looking for a short, my questions are,
1- If I rule out shorts on the top, anything special i should know before taking apart the lower unit?
2- Staying in drive is a fail-safe for the transmission, what are the odds the short plays apart? what are the odds i did real damage with the wrong oil?
3-What is likely wrong with the lower unit, if i did hurt something, and what am i looking for to diagnose and repair.

Thank you in advance and let me know if I can clear anything up.
 

F_R

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First thing you should be doing is verify the problem actually is in the lower unit. Disconnect the blue and green wires at the top and use a jumper wire to connect directly to the battery and see if it shifts as you connect / disconnect the jumper. Green is neutral, green and blue at the same time is reverse.

However in reading your story again, you already said the green wire is getting hot. Of course that indicates a short to ground.

After verifying the trouble is in the lower unit, go ahead and remove the lower unit from the motor. The electric part of the system ends at the solenoids under the cap where the wires enter the gearcase. No need to take it apart any further than that. Beyond the solenoids it is all hydraulic.

No you did not damage it with the wrong oil

BTW, that is Hydro-Electric not Hydro static. Helps us if we know what the topic is.
 

jimmbo

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As stated by F_R, the electrical part ends at the Solenoids. They control the hydraulics. Unless the driveshaft is turning, at minimum, cranking speed, the unit will not actually shift gears when you apply power to the solenoids. As you have learned the unit defaults to forward gear when something goes wrong. Resistance measurement of the Solenoids is supposed to be 5 - 6 ohms measured from each of the wires to the Solenoid cases. If a replacement Solenoid or wire is installed the connection(s) should be sealed with a piece of Heat shrink tubing.
 
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starkizzle

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I dont know why I keep wanting to say hydrostatic... Yes it is Hydro-Electric, my mistake. Could you explain how to jump? Ive gotten this far through videos and basic mechanical skills, but alot of this is new to me. This morning I followed the green wire the best i could, it is covered in decades of electrical tape, and I cant find a problem on the top end. It looks like the green wire runs all the way into the throttle/ignition. I had taken that apart too before i found the fuse thinking it was the ignition acting up.. It seems to be put back together right, but i took it back apart today. The green wire ends at the shifter switch, is that something that can go bad? the green wire covering even looks alittle melted. I could not open it up to check for any issues at the connection itself, but being sealed I would think it is ok. Is it safe to say this short is in the lower end?
 

F_R

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Sounds like it needs attention, no matter exactly where it is shorted. I'm not sure exactly where the disconnect is for the lower unit. But the cable comes up somewhere near the rear of the powerhead, and has two rubber sleeves covering a pair of knife connectors. Slide the sleeves away from the connectors and disconnect them. Now use a piece of wire to connect the green wire (coming from the lower unit) directly to the battery (+) post.. That should put it in neutral. (Has to be running). Do the same, connecting to both blue and green wires at the same time for reverse.

Results will give you a better idea of where the problem is.
 

starkizzle

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After disconnecting the green and blue wire I started the boat and hooked up a jumper cable from the battery to the green wire. For a moment the prop calmed down and it looked like it was in neutral, but then it died.. I tried again and this time it seemed like it just stayed in drive. Hooking both blue and green together did not put it in reverse either.
-Also, while trying this, in the heat, I hooked the jumper to the green wire going to the top end by mistake.. I noticed what I was doing when I felt the wire getting warm.. Does this mean my short is on the top end? Just a thought.. Anyway, what would still cause the boat to stay in drive?
 

F_R

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If it doesn't shift while jumping the shift wires, you need to take the next step and inspect the wires and solenoids in the lower unit. From your descriptions though, I think you have wiring problems in the boat also. But one thing at a time, get the shift working at the motor. One thing you might keep in mind is that push button switch costs $$$$ if you need one. How much do you love this boat?

EDIT: Sorry, the push button switch was used on Evinrudes. But the Johnson switch isn't much better.
 
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oldboat1

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For a first boat, that one may be a challenge. It sounds like you have a number of issues with a motor that can be tougher than average to work on. I had an 85 hp Evinrude version in decent shape, and got a lot of use out of it over a number of years -- so not saying it's a bad motor, but just that another model might be easier to start with. Do you need one that big, for example? Maybe a '70s or '80s 35 on a 16' aluminum would give you more boating time, and might be a lot easier to sell when moving on to something else. JMO
 

starkizzle

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I took the boat in trade last summer.. After it screwing with it for a year, a finally rebuilt the carbs this spring, and it came to life.. that trip to the lake to tune the carbs is when the fuse/neutral safety went.. i have been hunting down this electrical issue ever sense (the last two weeks). I am not really stuck on keeping this boat, but at this point would rather sell it in good running condition before selling, and for a older boat, it is in good condition.
My next question is, because I know the green wire is grounding, and without either wires connected the boat is in gear, can just run it in gear and keep the wires disconnected? I know it doesnt seem like the best idea, but I imagine I wouldnt have anymore burnt fuse either
 

jimmbo

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You can do that, You will have a Johnson Dock Buster, with silent neutral and silent reverse. It will make it harder to start when cold because the starter will have to turn the prop. Make sure you are facing open water cause it will move when it starts and set for fast idle. Replacing the shift wire might solve your problem, and would make for much easier boating
 

starkizzle

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I took the lower unit apart, the green and blue wire go under a cover, I remover the cover and appears to be a plastic disc Is broken and warped, is that right? I'm assuming I'm looking at the shift solenoid under this case but can someone point me towards what a good one looks like? And is there a way to check these wires now that it's all disconnectd? they don't look frayed or anything, although it does not look clean In there.
 

starkizzle

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the warped piece is metel not plastic, and possibly suppose to be like that, but the rubber underneath on what I'm guessingis the shift solenoid look toast? have I found the problem? - And does anyone want to buy a boat? haha
 

jimmbo

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Well you said the green wire was getting hot, that would be the top coil. The warped metal, is a wave washer, it is like a spring. The parts diagram doesn't show anything else between the wave washer and the solenoid, so the at rubber piece is most likely the end of the solenoid. Looking at the green wire, it looks like it might be damaged(kinked) where it comes out of the sheath. Did you ever do any resistance measurements?
 
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oldboat1

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I would clean it up some (electronic spray cleaner would be good). Green wire insulation looks broken to me too, but could just be the pic. Test from the knife connector at the powerhead, yes? Check continuity first -- don't know how the wire enters the solenoid. If looking at connections on the top, seems like they should not be exposed to contact with the metal wave washer -- but if that's a contact point, would do your testing from the top to that point. (been way too long, so not sure what the proper assembly should look like -- can't tell if a PO might have be doing some fixes).
 

jimmbo

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Service manual says 5- 6 ohm from wire to solenoid case. Checked for damaged insulation on wire where it may have contacted the gear housing, and where it enters the solenoid
 

starkizzle

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Could some explain how I actually test it with a meter? I'm not getting anything but I am not sure if I'm doing it right. Each of the solenoids only has one wire running to it, I just connect my positive lead to the end of the green wire and touch the negative to the side of the solenoid? Maybe I am not getting any reading because it is bad? I have the lower unit off completely if it makes a difference.
 
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