No crank!?! Electric issue??

[cameronr]

Hello everyone reading this.

I have a 1975 Evinrude #50573B

The motor runs (when crossing the solenoid)

I am having an issue with no crank when I turn the key. I tried the following steps before coming to ask for your advice.

trying a known working set of controls

• Replacing the solenoid
• Checking for neutral safety switch (there is not one that I could see)

From my very basic understanding the battery connects to bottom of the solenoid, the starter connects to the top. The small screw is for the ignition, and the other small screw is for the ground of the solenoid.


When I turn the key, power should be flowing

From the battery

To the solenoid closing the gap allowing power to the starter.

Since there is no neutral safety switch there is no other part that should be stopping power from reaching the starter

The three parts the could be killing my electric start from cranking is

Ignition switch (I know is good!)

Wiring harness (maybe)

Solenoid (should be good??)


Is there anything crucial I am missing that would STOP the engine from cranking?

 

[flashback]

I would meter your maybe.

 

[cameronr]

I would meter your maybe.

Going to try. I have watched so many videos and I’ve never felt so stupid trying to use a tool.

Give me an engine that the electric is working, I’ll get it running. That’s about it.

 

[Crosbyman]

do you have a fuse on that motor ... generally the B+ tapped off the solenoid to the key is fused

see typical wiring with the fuse on purple...also check any connectors for corrosion.

https://maxrules.com/graphics/omc/wiring/77-78_55HP.jpg

purple becomes a yellow-red to the solenoid via the neutral switch when the key is in START position

 

[cameronr]

do you have a fuse on that motor ... generally the B+ tapped off the solenoid to the key is fused

see typical wiring with the fuse on purple...also check any connectors for corrosion.

https://maxrules.com/graphics/omc/wiring/77-78_55HP.jpg

purple becomes a yellow-red to the solenoid via the neutral switch when the key is in START position

View attachment 395432

There is a fuse! 301 20A, I can’t really tell if it’s blown though.

 

[Crosbyman]

when in doubt replace it ... if it was not blown you will have a spare

google HOW TO TEST A FUSE .... utubes
and how to use a VOM

https://www.youtube.com/results?search_query=testing+with+VOM

 

[cameronr]

when in doubt replace it ... if it was not blown you will have a spare

google HOW TO TEST A FUSE .... utubes
and how to use a VOM

https://www.youtube.com/results?search_query=testing+with+VOM

Replaced the fuse, and the motor cranked for like 1 second. Not super confident in the fuse because I pulled it from an old motor. Going to go pickup a newer multimeter and see what’s going on

 

[flashback]

Going to try. I have watched so many videos and I’ve never felt so stupid trying to use a tool.

Give me an engine that the electric is working, I’ll get it running. That’s about it.

all you need to do is look for continuity, you will find a short somewhere.

 

[Crosbyman]

Replaced the fuse, and the motor cranked for like 1 second. Not super confident in the fuse because I pulled it from an old motor. Going to go pickup a newer multimeter and see what’s going on

so did you install the proper amperage rated fuse....??? then what happen did the fuse blow ??

if it blew right at KEY ON remove any extra accessories hooked up on the accessory post of the switch ... just pull the ACC wire and retry

if ok and fuse no longer blows at KEY ON you have a problem on the accc wire possibly wiring grounded or a bad accessory drawing to many amps

yet if it suddenly blows during START only you have a short on the START wire or a bad solenoid drawing to may amps

disconnect the start control wire on the solenoid post (check color code from switch S post ) and turn the key to START... if the fuse blows the wiring is grounded - chaffed somewhere

if it only blows with the solenoid connected then the solenoid is suspect

 

[cameronr]

so did you install the proper amperage rated fuse....??? then what happen did the fuse blow ??

if it blew remove any extra accessories hooked up on the accessory post of the switch ... just pull the ACC wire and retry

if ok and fuse no longer blows you have a short on the ACC wire or a bad accessory ....

I went to the store to get a new multi meter, I clicked the positive on the small positive side of solenoid, negative on the negative, and the solenoid clicked. Then magically the key started working again.

Not sure if god was just on my side but the electric start works now, I’m sure it was the fuse, not sure why it didn’t work earlier.

Thank you so much for your assistance. I would have never located the fuse. Just gotta run all of my cables, install the lower unit, and should be water ready! Thank you, again!

 

[Crosbyman]

just carry proper sized ...spare fuse in case ... not finding a problem can be worrisome 10 miles out

thanks for your feedback

 

[saltchuckmatt]

Yes good be a blessing could be an omen .

Gearcase was off, new water pump I hope?

 

[cameronr]

Yes good be a blessing could be an omen .

Gearcase was off, new water pump I hope?

Not quiet yet, got 3 outboards I’m working on right now. All 3 now run, now time to prepare with water pumps, grease, and ensuring all the bolts I took off are back on!