Boat won’t start, I’m at a loss

Charvid12

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Joined
Jul 8, 2021
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4
So I was replacing the fuel pump on my 1975 johnson 70 and I went too start it and nothing happened so I tried to jump the solenoid and the motor turned over but wouldn’t spark. I unplugged the kill switch and still nothing at a loss
 

Crosbyman

Vice Admiral
Joined
Nov 5, 2006
Messages
5,650
check for any blown fuse in the wire harness under the side clip


if ok ten.... holding the key on start.... wiggle shifter, cable harness, accessible wires .....

if nothing basic testing begins see basic/similar diagram 1978 and up check for +12 arriving at selenoid control post while in START ... if nothing work back

 
Last edited:

Charvid12

Recruit
Joined
Jul 8, 2021
Messages
4
I tried moving the shifter around when I was holding the key nothing happened still. I can only see one fuse under the hood of the motor and it’s good. Is there any others I could be missing?
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,418
Only 1 fuse.----Charge the battery ------Load test the battery.------Take starter apart for inspection , ohm test on armature , perhaps new brushes.
 

Charvid12

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Joined
Jul 8, 2021
Messages
4
Only 1 fuse.----Charge the battery ------Load test the battery.------Take starter apart for inspection , ohm test on armature , perhaps new brushes.
The battery is hot I just pulled it out of the water when this happened, and when I jump the solenoid the motor will turn over fine it just won’t spark.
 

greggilo

Cadet
Joined
Sep 20, 2014
Messages
22
Check for voltage at the start solenoid. The battery cable is on one end terminal and the starter on the other terminal. There should be a cable coming from the wiring harness which is the power to the key switch. If it is connected to the starter side it will not start. There are two smaller wires on the start solenoid- one is key power and one is ground. If you jumper the key power wire to the large battery side terminal of the start solenoid the starter should turn. If not measure the starter side of start solenoid for 12V going to the starter motor. If so then you have a bad starter.
Another way to check is to use jumper cables and ground one and place the power straight to the starter to see if it turns.
 

Charvid12

Recruit
Joined
Jul 8, 2021
Messages
4
Well guys I unplugged the controls to the motor and jumped the solenoid and it fired right up. So I guess I need another set of controls. I appreciate all of y’all’s help
 

Crosbyman

Vice Admiral
Joined
Nov 5, 2006
Messages
5,650
could be just a frayed, shorted or broken wired A "set" of controls may be over kill $$$ if you can track down the impairement causing the problem

test each wire end to end with a ohmmeter individually to confirm continuity then check each wire for any continuity with others in case one is shorted to another wire

then test each wire to ground in case one is shorted to ground.

fixing a bad wire will be much less costly
 
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