72 hydro elctric shift 50 hp Johnson

[Freddyb18]

Hello all!

There are a lot of really good threads on here, and I was wondering if anyone can help. ***This is my first boat and motor, I am pretty handy with working on vehicles, electronics, etc, but master of any of those things I am not***

I recently bought this engine. It has been sitting since '03, but kept well. The seller told me that it needed a new starter solenoid, he was right. I replaced the starter solenoid, spark plugs, impeller, and lower unit oil. We had jumped the starter solenoid to see if we could get it to start before replacing the plugs and solenoid. The starter engaged, but would not turn over. After replacing the plugs and solenoid, we went and got fresh gas and 50:1 oil.

1st attempt to start with new gas, and it did nothing, including engaging the solenoid. I read my manual and discovered the fuse had popped. I replaced the fuse and VROOM... duh. I noticed that the water pump did not kick water out of the holes at the back of the engine about midway up.(Could this be something clogging the "exit tube" of the water pump? Any other ideas?) I got the engine to turn over, and it ran like a champ. I could not, however, get the engine to turn off at the switch. I had to close the choke flaps to kill it.

I have a 5 prong ignition switch (I did remove the wires and put them back on before finding out that there was a fuse, so there is a slim chance I did not put them back together correctly.)

BAT - Red/Light Blue Stripe
M - 2 Blacks
S - Black/Yellow Stripe
A - White
M - 3 Purples (Purple, Purple/White Stripe, Purple/Green Stripe)

I am not sure what needs to happen to get this thing to turn off at the switch. Is it possible the purples and blacks should be switched (maybe wrong "M's")

I believe the purples go to the choke solenoid (also not working currently, but could be the separate choke toggle switch in shift box)

Any help? Questions?
Thank you in advance for reading.

 

[Faztbullet]

Re: 72 hydro elctric shift 50 hp Johnson

Is this switch on the dash or in control box? You should have a toggle for the choke and if you have the manual as suggested check the wiring diagram for the switch as it does not look correct..

 

[F_R]

Re: 72 hydro elctric shift 50 hp Johnson

The switch wiring is all screwed up. Should be:

Bat: Red/blue stripe
STart: White
Ignition: All purple wires
M: Two blacks, one is grounded
M: Black with yellow stripe

EDIT: oops, that ain't right either,

A purple wire goes from Ignition terminal to the choke switch. Purple/white stripe goes to other side of choke switch.

A purple wire goes from Ignition terminal to the shift switch (MIGHT be purple/green stripe) Either way, a purple/green stripe goes from that same shift switch terminal to the motor.

A purple wire goes from the Ignition terminal to the hot horn. A tan wire from the motor goes to the other side of the hot horn.

Finally, a solid purple wire goes from the Ignition terminal, back to the motor.

EDIT EDIT:
Cable must have a YELLOW plug back at the motor end. Red or black won't work.

 

[Chinewalker]

Re: 72 hydro elctric shift 50 hp Johnson

If you're starting the motor on muffs you likely won't get much water out the holes in the leg. They are an exhaust relief and only really come into play when the lower unit is submerged and the exhaust/water can't force its way down under water at idle - so it exits those holes...

 

[Freddyb18]

Re: 72 hydro elctric shift 50 hp Johnson

Fazt: This is a shift box, there is a toggle switch that appears to be switching... It also appears to have one or more of the purple wires going to my shift toggle switch inside of the box (electric shift) I cannot find a diagram in my manual that covers my exact engine. I will look again, but does this clarify anything for you?

Thanks for the reply!!!

 

[Freddyb18]

Re: 72 hydro elctric shift 50 hp Johnson

Thank you all a ton!

The water pump works like a dream in the water (not on muffs). Thanks!

5 prong switch should have been wired as such (going clockwise):

red = Batt
2 blacks = M
white = S
3 purples = A
black/yellow = the other M

(Stupid me ) ;P

AGAIN, THANK YOU FOR ALL OF THE HELP! HOPEFULLY THIS HELPS SOMEONE ELSE WITH THE SAME PROBLEM!