1969 Johson 115hp hydro electric shift

[Maxwell-8]

Hello, I am new here. I have a problem with my 1969 Johnson V4 outboard motor.
It has hydro electric shift. When the motor is out of the water it shifts fine in forward, neutral reverse. But once the engine is in the water it does not want to go in reverse.
Any idea what it could be? worn gears? solenoid rod out off spec?

Another problem I am heaving is that the motor runs fine on idle, and in the mid an hige rev-range. The lower rev range is is shaking quite a bit.

Thanks in advance for the help

 

[racerone]

Rough running , start with a compression test.----Post the numbers here.----In my opinion the electric shift is easy to take apart for inspection / repair.---What oil are you using in this gearcase ?----Any water in the gear oil ?-----For reverse it takes higher oil pressure to compress the clutch dog spring.-----Perhaps pump is worn.---Strainer screen plugged.----Or shift piston bore is contaminated.

 

[Maxwell-8]

Rough running , start with a compression test.----Post the numbers here.----In my opinion the electric shift is easy to take apart for inspection / repair.---What oil are you using in this gearcase ?----Any water in the gear oil ?-----For reverse it takes higher oil pressure to compress the clutch dog spring.-----Perhaps pump is worn.---Strainer screen plugged.----Or shift piston bore is contaminated.

Compression is 135psi on all 4. Sparkplugs have been replaced previous season with low hours on them since.

The previous owner had a shop preform a oil change annd the but in the wrong oil. I changed to the correct oil for the electro-hydro system.
I will take it apart this evening and inspect the possible problems you mentioned.
I thank you for your advice. This system is rather complicated compared to other ouboards.

 

[racerone]

To me it is elegantly simple !!!-----Very good , reliable design in my opinion.----Shifts very quickly and rarely, if ever needs solenoid adjustment.-----

 

[racerone]

To me an 8 speed automatic in a pickup truck would be complicated !

 

[Maxwell-8]

The previous owner never had this problem when using regular gearcase oil.
What this be a sign for a worn pump?