Hooked up battery backwards to yamaha 70 etlj 1986

[nayborbob2]

Help

not only did I hook it up backwards after it sparked at me, I also turned the key. Must have been out of my mind. now I get nothing... but the starter turns w/ 12V and the 3 relays on left side, starter relay is 1 of them, all worked when I applied voltage with them out of the engine. So I think maybe I have a blown fuse. its #19 in the electrical diagram... but where is it? any help greatly appreciated.

 

[robert graham]

Should be an in - line 20 amp fuse right near and under the black plastic electrical cover on the starboard side of motor…
It’s easy to find and replace….keep a spare on hand for future….I guess most folks have hooked up the battery backwards at some time, wheather they’ll admit it or not!

 

[nayborbob2]

Should be an in - line 20 amp fuse right near and under the black plastic electrical cover on the starboard side of motor…
It’s easy to find and replace….keep a spare on hand for future….I guess most folks have hooked up the battery backwards at some time, wheather they’ll admit it or not!

Ok found that fuse and it was blown, it was 10A and there was a spare inside the cover sealed in a plastic tube... Looked original .. That also was 10A. Hooked it up and now I can make the trim motor work but only 1 way, down... Trim switch in throttle is what got me here, it failed last year like stuck in 1 direction. I had to disconnect the battery. I wonder if by turning on ignition with reverse polarity I fried the switch on the control, it has ah715079 identifier... Wonder if I can test that, or what to check next.

Thanks!

 

[boscoe99]

Throttle handle trim switches are known to have a higher failure rate given their exposure to the elements. If it is the age of the motor then it is long over due to be replaced. The battery being connected backwards should not have affected the trim/tilt switch.

Each to trouble shoot. Reverse the green and blue wires to the switch. If the problem remains but is assbackwards, it is the switch that has failed internally.

 

[nayborbob2]

Throttle handle trim switches are known to have a higher failure rate given their exposure to the elements. If it is the age of the motor then it is long over due to be replaced. The battery being connected backwards should not have affected the trim/tilt switch.

Each to trouble shoot. Reverse the green and blue wires to the switch. If the problem remains but is assbackwards, it is the switch that has failed internally.

I figured out the trim problem, I forgot to connect the wire that activated the up relay. I think the part I mention above is the problem. If I put 12v to energize the start relay the starter engages... The Q is where to get that part

 

[boscoe99]

What part?

 

[nayborbob2]

I figured out the trim problem, I forgot to connect the wire that activated the up relay. I think the part I mention above is the problem. If I put 12v to energize the start relay the starter engages... The Q is where to get that part

What part?

this one...used to be $15 before covid, now cheapest I found was $66

 

[99yam40]

looks to be neutral start switch.
should be easy to test with an ohm meter when disconnected or voltmeter when hooked up and turning the key to start.
should allow starter to engage only when in neutral

 

[nayborbob2]

looks to be neutral start switch.
should be easy to test with an ohm meter when disconnected or voltmeter when hooked up and turning the key to start.
should allow starter to engage only when in neutral

Found replacement online at Digi-Key, p/n ‎SW1264-ND‎, $6! just ordered it and will test the old switch after work. Thanks for all the help!

 

[nayborbob2]

Found replacement online at Digi-Key, p/n ‎SW1264-ND‎, $6! just ordered it and will test the old switch after work. Thanks for all the help!

In the end, I don't think the reverse polarity damaged my neutral switch, its mechanical. What I found was I must have broken off the little switch button when I was investigating the no start (on control re-assembly) when I was looking for the fuse. So, the fuse was all I needed to replace. Thanks all for the help. Motor is back to running, planning a shakedown cruise this weekend.