ignition switch wiring/Push Button

thunt1977

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1975 25 hp johnson im trying to wire an ignition switch and wire harness to a 1975 25hp johnson outboard the3 ignition switch has 4 posts all together no m terminals when i had everything hooked up asnd tried to start it , it cranked over sluggish then when i left the key in the run possition both coils started smoking and am wassuming are now dead what did i do wrong and how can i aviod that in the future when i go and work on my 115hp evinrude that is on my boat?
 

racerone

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The coils do not use battery voltage to make the spark.----Lesson learned on your part.-------You need new coils , condensers , points, wiring diagram and the proper switch.
 

F_R

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Yep, sounds like you used a switch for battery ignition. Death to magneto systems.
 

Scott Danforth

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To explain in laymans terms.

magnito ignitions use a switch to ground to kill the spark (simply turning the motor over will make them run)
battery type ignition provide power to the coil and pulse the negative side of the coil to make spark

by using the wrong switch, you put power where it isn't supposed to be and turned your coils and points into toaster elements
 

Joe Reeves

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1975 25 hp Johnson... Ignition switch has 4 posts all together... No "M" terminals... It cranked over sluggish... Left the key in run position... Both coils started smoking...What did i do wrong... How can I avoid that in the future when I work on my 115hp Evinrude?

As "Racer" states in not so many words... you've expertly destroyed the magneto system of your engine. Coils, points, condensers, probably some wiring will need replacing.

The ignition is self contained. Battery voltage is NOT to be supplied!

What you did wrong was to guess as what to do which usually results in unfortunate encounters.

You need a marine ignition switch with six (6) terminals marked B, C, A, M, S, M, a service manual which should be studied thoroughly, and a proper wiring diagram (normally in the manual)

B = Battery..... C = Choke..... A = Accessory..... M = Magneto..... S = Starter Solenoid..... M = Magneto.

The two "M" terminals =..... 1st "M" = Wire from one set of magneto points or power-pack if so equipped..... 2nd "M" = Wire to other set of points or ground if power-pack equipped. Key OFF = Two Ms connected, ignition grounded/shorted out.----- Key ON = Two Ms NOT connected, ignition engaged.

A strong suggestion here is NOT to do anything to that 115hp you mention without asking advice here and/or having a service manual for that model also.

Hopefully your mistake has not been too awfully expensive. We'll try to help you with whatever problems you encounter in the future.
 

F_R

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Without knowing what year your 115 is, it can be either battery CD ignition or mag CD and those two take different ignition switches. However, a 5 or 6 terminal ignition switch can be used on either type, as well as your 25hp. In either words, it is pretty Universal. Have we confused you yet?
 

thunt1977

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no nothing confusing, it seems i get advice that can go either way, for instance that wiring i tried came from a repair manual and a self proclaimed "boat mechanic". which that seems to be the wrong way. its pretty much trial and error for me with these outboards i don't know anyone that's into boats but me really and you tube, hell of a way to teach yourself something new but it is what it is. thanks for the very valuable info. what are the chances i just simply fried an old coil and not the entire magneto system? i cant seem to find new coils for that 25, but i do have the coils, and power pack on its way for that 1978 Evinrude 115hp.

my 1972 StarCraft came with a 1972 Evinrude 85hp /w prop drive and i am going to be putting a jet pump on the 115hp. seems that the 85hp would enough motor but there isn't a jet pump for it. The 85hp and boat have an electric shift the 115 does not will the plug from the throttle control work on the 115? or do i need a different throttle control that has the 2 handles on it? is there a way that i can wire a push button starting system instead of a key switch? if i am not going to use the 85hp should the throttle control that is on the boat come out and go with the motor?

anyway tons of questions, thanks for your in site into the key switches. i'll start new wire harnesses for the 115 and 25. I would ultimately like to put push button starting systems with the motors i do get up and running. is that a feasible idea or do i just need to stick with keyed switches? (I'm a master plumber not an electrician, which shouldn't mean to much, but ...)


Thanks again.
 

F_R

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1. Your 85 and 115 have very different electrical systems and are not compatible.
2. The controls came with new motors and are SUPPOSED to go with used motors. However, that seldom is the actual case
3. You can use push buttons to start and stop your 115. You need wiring diagrams to know what the heck you are doing
4. Back to the coils. They are readily available right here at iboats. Yes, $$$ but that's what happens when we screw up. You might get away with not replacing the points--just depends.
 

lmuss53

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Sep 9, 2008
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If the old 85 has the electric shift lower unit, a great deal of the resale value on that motor is keeping it with the controller that it uses. I would pull that off as a package and keep it together for resale, or reuse on another boat if that's what you have in mind.

My advice to you right now sir, is read, read, read. Spend some time on these forums, mining for information from the guys who replied above here, Get the factory manuals for the motors you own or buy and read them. Make yourself familiar with what you have and how it works, BEFORE you tear into things.
 

oldboat1

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Check the sticky up at the the top of the forum ("top secret files") for wiring diagrams from Master Tech Marine -- a couple for '70s 25s, incl the switch. Check for the 85 as well.
 

thunt1977

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Jan 18, 2018
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cool thanks for all the valuable info everyone.

so i ordered some new ignition switches that were labeled marine switches but don't have the for mentioned letters on them instead they are labeled ...... --
L B
S B
G
the top terminal is blank which l labeled -- there is 6 terminals on them can i still use these switches ? they are Briggs and Stratton brand but cant seem to find anything online that labels each terminal; or says what they are what so ever
 

Joe Reeves

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Briggs & Stratton?? What, you must have gotten it mighty cheap, otherwise you would have bought something known to work. Such as this one, from right here at iboats
https://www.iboats.com/shop/electri...b-1-boss-screw-push-to-choke-marineworks.html


Wow F_R! I'm astonished that the 6 terminal marine ignition switches are selling so reasonable... $16.16?... For something in the marine line, that's almost free

Thunt1977.... LB, SB, G ??... You ordered some new ignition switches?... plural?, more than one? Why? You only need one. Wrong ones, return them.
 

thunt1977

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Jan 18, 2018
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1978 evinrude 115hp ignition wiring using a push button iginition switch

i have a 1978 evinrude 115hp im trying to get running the wiring was pretty shot when i got it the power packs and coils failed on the ohm meter so i replaced 2 power packs and 4 coils how do i wire it with a push button ignition with out the remote throttle control, or standard key ignition switch. not sure where to go from here. i can get it to turn over but i believe i still have no spark. with out the throttle control wired to the motor and no existing ignition switch. ive looked at several wire diagrams and still nada when it comes to wiring a push button switch i was thinking push button start with toggle switches in place of the keyed switch.
 

Silvertip

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Have you really thought this through? To start the engine (just to engage the starter) you need one push button. To stop the engine you will need another. To activate the choke you will need another. During the start process you would need to hold both the start and choke/primer buttons. The original key setup is far simpler, far more secure and a lot more handy. There is no difference in wiring the system. It is simply that all three switches are built into the key-style ignition switch. Positive goes to one terminal on two of the three switches. The other terminal goes to whatever that switch controls. 1) starter solenoid, 2) choke/primer, and 3) magneto. The magneto switch has no power on it. It connects to the other magneto wire. Unless you hide another switch somewhere, anyone can drive away with your boat.
 

GA_Boater

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thunt1977

Merged both threads so we know what you're trying to do.

Silvertip has the right advice - Use an ignition key switch.
 
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