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Won't engage forward???

J

Jlgonzo

Member
I guess I need help again guys.....1968 johnson outboard 100hp electramatic will not go into forward gear. Got it on the lake today, fired up, went into reverse just fine and neutral but could not get it to engage foward. Motor revs up just fine. Going to test the shift solenoids tomorrow, any other ideas? Clutchdog perhaps?
 
Describe how it failed.-----There is no " solenoid "---It is an electromagnet.----There is no clutch dog.--------Do the following.----See if 12 volts goes to the green wire at the motor when forward is selected with key in " on " position..----Post the ohm reading of the electromagnet coil.-----Likely it is the tab broken off the forward clutch spring.-----All easy fixes for me.
 
I was under the impression that there was a neutral and reverse solenoid in the lower unit. I'm not sure how forward gear is applied but I think the vaccume switch needs to operate correctly in order to complete the circuit also preventing it from jumping forward if power is built up and points are aligned correctly. I will test it out tomorrow and post my results
 
Can't seem to post a pic on here but the v4tl diagram does show a neutral and reverse shift coil I guess I'm not sure where they are located
 
Sorry----but nothing to do with a vacuum switch.-----The electromagnets are located inside the gearcase.----Guessing on how this unit works will not help you !!
 
I'm trying to learn as much as I can not guessing only going on manuals and any info experience boaters are willing to give. I really appreciate the advice sir
 
Check for 12 volts going to green wire with control in forward and ignition " on "---Report what you find.----And check ohms on the forward electromagnet, report what you find.
 
That 100hp lower unit is pretty tough. It was also used on V-8 inboard-outboards. If the lower unit is not full of water, most likely it is an external electrical problem.
 
Find the bkue and green wires at the motor.----Turn key " on " and put control in reverse.-----Should be able to turn prop counterclockwise and not clockwise.-------Turn key "off " .----Slide rubber boots on wres back and connect blue to green.----Turn key " on " and see if you can turn prop clockwise and NOT conterclockwise.
 
The basics..........

At the powerhead, disconnect the wires that lead to the lower unit, check the ohm reading on the wires that lead ro the lower unit. That should be approximately 8 ohms. The reading on both wires should be identical. Is it? If that reading is as it should be, the electromagnetic coils are okay.

The wires that you disconnected at the powerhead... the ones that are part of the powerhead wiring harness... with the key in the ON position, you should have a full 12v at each wire depending on which gear you have the control set to. Do you? If so, go to the next step..........

Connect those powerhead harness wires to the wires leading to the lower unit and repeat the voltage test as above. Even with the wires connected, depending on which gear you have the control set to... you should still have a full 12v reading at the connection. If a voltage drop exists on this test, the shift switch is faulty or a bad connection exists somewhere between that connection point and its supply point.

If all of this is as it should be..... testing as per racerone's instructions above (#12 reply) would be a good test for the shift springs.

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Just for general info on the shift system for you.........

There is a hub splined to the propshaft for each gear.... a heavy duty shift spring attached to each gear.... an electromagnetic coil positioned at the forward and rear portion of the gearcase.

When 12v is applied to the forward coil, it attracts the spring attached to the forward gear and that spring wraps around the forward hub which is splined to the propshaft like a Chinese finger trap which in causes the propshaft to turn. The same scenario holds true for reverse.
 
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Just a bit of advice: There is "Electramatic" shift (yours), and there is "Hydro-Electric" shift (very different). While doing tests, make sure you do Electramatic tests. Hydro-Electrics apply voltage to both blue and green wires at the same time for reverse. If you apply voltage to both wires at the same time on your Electramatic it will go into both forward and reverse at the same time and lock up solid. If you do that while it is running, something is likely to break $$$$.
 
Didn't run away yet lol, just got busy with family and Easter stuff. Just clocked out from work and sitting in front of the boat now. I just tested the shift selector and it's giving power in the correct gear I'm going to test the rest right now I'll post results in a few
 
Attempting to take reverse coil out to check forward coil. Is there a trick to getting it out with the wire intact? The wire will shear off if I pull the coil out. Do I have to drop the lower unit for this process?
 
With your help I'm going to know this thing from top to bottom! I think I'm just going to replace both coils, do you know anywhere I might find them besides this site? Looks like $370 for both on here and I can't spend that much right now
 
????-----At this time you do not know what is actually wrong !-------No way that I would replace a working coil.------I would invest that money in a seal kit.-----Or perhaps some liquid refreshment
 
I have all new o rings seals and gaskets on the way my concern was the age of the wires, the coating is already crumbling off. Do you think it's worth the time to put new coating on or solder new wires to the coils?
 
I ordered a new omc foward coil to be on the safe side ( having a new part with new wires seems like the way to go) and seeing it's going to be a pain in the butt to get to. Holding off on the rear for now being it is so easy to access. New rings and seals will also be put in. Anything else I should do whileI have the lower torn apart?
 
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