1992 Mariner 75 hp (3 cyl) need help!

[Adeal]

I am having trouble getting my 1992 75 hp mariner outboard motor (3cyl) to start and it seems to be the ignition switch is bad. I checked wires and fuses for power and 3 of the 6 prongs on the ignition switch were not hot. I have a black and yellow wire that runs from the switch and has a 2 prong connector which is not connected to anything and I cannot find anywhere it would plug in to. I do not have a manual but I have one on order! I am trying to find a replacement switch or a switch diagram but cant seem to find one online. Any advice on replacing the ignition switch would be greatly appreciated!

 

[CharlieB]

Re: 1992 Mariner 75 hp (3 cyl) need help!

That Black w/Yellow wire is the 'Ground-to-Kill' wire that connects the ignition switchbox to the ignition switch where when turned to the 'Off' position should connect to the solid Black 'Ground" wire.

At NO time shoud you EVER have 12 volts to this wire, that would fry the ignition switchbox.

You may have an internal short in the ignition switch, grounding the Black/yellow wire and causing a 'No Spark' condition.

Test for spark, if NO spark, Un-plug this Black/yellow and retest for spark.

Warning, starting the motor with this wire UN-plug will not allow you to kill the motor without disconnecting the fuel hose and waiting for it to run out of fuel.

 

[Adeal]

Re: 1992 Mariner 75 hp (3 cyl) need help!

Thanks for the info, the black and yellow wire does come together with the black wire into a 2 prong connector. I am not sure if this is suppose to connect somewhere? I am including a pic so yall can see what I am talking about. I am not real sure what I am suppose to do when you say "unplug" and test for spark. Also, I hear a click when I push in the choke but go to turn the key and nothing happens. All other electrical works fine. trim, lights etc. and both batteries are charged. Should I just assume ignition switch or what else should I check?

 

[ONERCBOATER]

Re: 1992 Mariner 75 hp (3 cyl) need help!

you could try disconnecting the kill wire(s) from the ignition switch then start engine/check for spark... it may well help you isolate the issue. myself i would likely have a friend try to start her with the kill bypassed(disconnected) at the engine, and a wire connected that i could ground to kill the engine should i wish her to stop.
I know the last ignition switch i took apart had a star of david typ pattern to it... 3 hots, three grounds. it went...ground, hot, ground, hot, ground, hot... three hots 120* apart and three grounds 120* apart... it needed cleaning and relubing. you should be able to check your switch with a multi meter, remember to look for contack (ohms) between ea of the wires in all three positions of the switch. what mine did was essentially heat up the starter solenoid.battery (and had a spare unused terminal hot) to start, then to kill it grounded the coil to neg battery/block. very nice and simple. what i replaced it with was one that had choke included in the switch by pushing it, and it had a ton more connections. Just remember that unlike a car once the outboard is fired and running it needs no further input from the ignition switch or battery to sustain as it is a magneto system.
on that note lol, i have seen several people over the years try to put automotive ignition switches in their boats with dismal results and expensive repairs needed.

Sean

 

[Adeal]

Re: 1992 Mariner 75 hp (3 cyl) need help!

I have disconnected the black and yellow "ground to kill" wire from the ignition switch and tried to start it but still nothing. Should I try to disconnecet the black wire as well? I do not know much about motors so when you say "check for spark" im not real sure what im looking for. Should i disconnect the black and yellow wire from the switchbox on the motor or from the ignition switch itself? The only sound i get is when I push the choke and it clicks as if it's making a spark. Again thanks alot for the help!

 

[ONERCBOATER]

Re: 1992 Mariner 75 hp (3 cyl) need help!

the sound you hear when pushing choke is the sound of your solenoid kicking for the choke....
to check for spark (not for good spark but just for any spark at all) you can remove spark plug, ground plug to block then pull cord or use starter while looking at plug gap, there should be a blue/white spark in the gap. this will only tell you that you do or do not have spark...not that it is sufficient for combustion.
If the wire you removed/isolated is the kill wire...and you still do not have spark....then i would go back to the engine and test that lead to look for a short to ground on it. When the manual gets there you will have the trouble shooting proceedure laid out before your very eyes. before you remove any other wires...period i suggest that you take several good quality close up pics of the engine with cover off, from various angles... that way when you are putting things back together you will have a nice reference.... often nice to take pics as each part comes off too... incredible help....trust me.

Sean

 

[CharlieB]

Re: 1992 Mariner 75 hp (3 cyl) need help!

Will the starter turn the motor?

If the motor is not cranking then this is a whole different ball game, instead of looking at an ignition related problem you should be checking the starter relay, use a test light or volt meter to ensure that the starter relay is receiving power from the ignition switch, if so and it still does not 'click' in to make contact to crank the motor you may only have a bad relay.

 

[ajgraz]

Re: 1992 Mariner 75 hp (3 cyl) need help!

Agreed, first off is starter engaging? Turning over?

Second, to answer a previous question: yes, disconnect that blk/yel kill wire from the switchbox before checking for spark, to ensure the kill circuit is out of the equation. The kill wire also routes through a mercury switch (which kills the motor if it tilts out of the water, e.g., hitting a submerged object), and sometimes the merc switch can go bad and ground out.