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Johnson 100Hp early 70bs Hydro Drive

L

liv

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"Hello, I hope someone can hel

"Hello, I hope someone can help with some questions on this motor.


problems I am experiencing other than the shifting/reverse issue covered with this type of unit are as follow.

When starting, the fuse blows, it cranks ok. Is a 20 AMP fuse required ?

Question 2

Tracing the wires from the Throttle control box so I understood what was going on with the shifting problem, I noticed a brown wire that went into the bottom right cylinder.....it is not connected but has a spade tip on it and rests in the engine compartment. I am thinking its some sort of accessory because in the Throttle control unit, the same wire just sits there. What is it ?


Question 3

Gear oil issue, I drained the oil and replaced with proper oil. The color of the old oil was like a butterscotch with a milky texture.

I was told this was because of water contaminating the lower unit. thinking about this, would it be correct in assuming, if water is entering the lower unit, would this possibly be the problem with the shifting since electrical components are located in the lower unit.

Any help would be appreciated. I just wanted to know because I would have liked to run the boat once or time this fall with an overhaul in the winter.

Liv"
 
"Do you have an amp meter that

"Do you have an amp meter that you can put in series to check draw on fuse. You might want to get a manual for electrical diagrams to locate draw.
With the key on, ground the brown wire and see if the over temp horn sounds off. The temp is in the cylinder head and should have a tan wire coming out of it.
Those electric shift lower units do not like water. Drain and flush lower unit and fill with proper oil (prieum type C). Install new seal washers on drain and vent screws."
 
"Thanks David,

I've bee

"Thanks David,

I've been making some use of my meter. I will check the draw and I will be buying a service manual for this motor.

In the end I do think it will have to be serviced and overhauled, but i like to inform myself. As it is now, I believe the solenoids are shot. The old oil was of the wrong consistency and when I did crank the motor this afternoon I noticed the 2 wires going down into the lower unit were smoking and getting quite hot, even with new crankcase oil and water mufflers running.

Thanks for the info on the tan wire in the cylinder head, now I know what its for and will hook it up. It seems the previous owner broke the brown wire from the the control unit, I;'m still not sure where either end hooked into. All I have is 2 lonesome spades, open at either end, and a busted brown cable at the multipoint connector.. I'm sure the schematic will reveal more information.

Speaking of the multipoint connector, i've drawn up a schematic and would like to post it for future reference as well as some pics of the motor. Is there a place to list those for other readers with similar problems.

Oh , the red white wire changes color ( from throttle control unit )at the multiport connector to brown ( tan )to a factory splice which changes it back to red and fuse holder.

Thanks again, hope something starts this thing tommorrow. I have spark, new plugs, fuel
( perhaps its contaminated by old fuel ), cqarb cleaner injected into carbs, good crank...we'll see."
 
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