Kill switch issue possible short?

[Ryant10275]

I picked up a 96 Rinker 180 with a mercruiser 3.0 and an alpha 1 gen 2. Needed a head gasket and impeller. Fixed all that and had some issues with the wiring under the dash had ignition and would run but no accessories. I believe we fixed the wiring because everything worked and boat ran. Took it out on the water yesterday and started going across the lake. Tried opening it up full throttle for the first time and as i backed off the throttle and slowed down the boat died. Would turn over but no spark. Found the wires behind the throttle On the kill switch “quicksilver 3000” to be very hot and it kept tripping the reset button next to the key. So today i tried looking for the issue and i can’t find any bare or shorted wire. I did notice as soon as i turn on the kill switch it dramatically dims the lights on the gauges.

 

[Bondo]

I believe we fixed the wiring because everything worked and boat ran.

Ayuh,...... Welcome Aboard,....... Go back over the wirin' ya "Fixed", as it sounds like the ignition circuit is overloaded, or has a short in it,.....

 

[Ryant10275]

Ok will do. Have a buddy that doesn’t know boats but is an electrician to come help me some day this week. Would it have taken that long to trip everything out? I’d say a good 5 minutes of idle and 2 minute trip at power before it shut down on me.

 

[alldodge]

With the wires getting hot behind the shifter as Bondo mentioned that's corrosion.

Which ignition system do you have? I'm thinking EST distributor

 

[Ryant10275]

My ignition system looks just like the picture. The two wires coming directly from where the kill switch is are purple. I also have yellow with red stripe coming out towards the top that i noticed go behind the dash also. Could this possibly be something bare or faulty inside the throttle assembly?

 

[alldodge]

The pic only shows the ignition side, which the purple wire also goes to the alternator and choke

Power from the motor comes up on the red/purple wire going to the key switch. The purple wire is ignition which goes to the kill switch and then to the gauges and back to the motor. The yellow/red wire is the start circuit and comes from the key switch, to neutral safety switch to the slave relay on the motor

 

[Ryant10275]

I appreciate all of the help guys! I have printed out these diagrams and the ones in the sticky for my buddy that’s going to stop a night and help me sort this out! I just want to get out on the water!

 

[gm280]

First time I've ever heard a "kill switch" killing the entire boat, motor and everything else. I mean that IS a real KILL switch!

 

[Ryant10275]

It didn’t kill everything else just the motor. Motor still turns over in between it popping the reset button next to the key.

 

[alldodge]

Might just be a gauge drawing to much current.
Could disconnect every gauge, and alarm and then re-connect until the issue starts again

 

[Ryant10275]

Is the kill switch wiring energized or grounded on this mercruiser?

 

[Ryant10275]

Ok, so spent 4.5 hours on it tonight. Traced every wire checked every connection everything looks fine. the wiring is how it’s supposed to go. Could not find any issues at all and could only replicate the issue once. After it started tripping the reset and got warm wires at the kill switch we stopped messing with it to cool down and had a bite to eat and could not get it to happen again. Currently about as lost as i could possibly be, seeing as we traced every wire and connection. At this point what do i do? Throw it back in the water fingers crossed i don’t get stranded and have to be towed again? Any insight would be more than appreciated

 

[gm280]

Please don't try to use the boat until you fine what the real problem is/was. Just because it isn't doing it now doesn't mean it won't when you are on the water. And remember, a fire on a boat out on the water don't allow you any place to run away...

 

[Ryant10275]

I don’t know how to find the problem. We traced every wire took everything out of the loom followed every connection.

 

[alldodge]

The kill switch is a pass thru like a light switch. When in normal run mode it is passing 12V, it kills the motor with it opens

If wires at the kill switch is getting warm then a good chance the switch may be the issue

 

[Ryant10275]

Alldodge that was our guess but the switch was testing fine but once again I’ve only gotten it to do it twice in about 7 hours of pissing with it.

 

[alldodge]

It can test fine with a meter because a meter only uses microvolts to check. When your drawing 10 to 15 amps thru the switch this would be a different issue. The key to the issue is the heat build. If heat is building then there is resistance at the location

 

[Ryant10275]

Going to just order a switch and see what happens then thank you. Like you said we figured the source of the heat should be the source of the problem

 

[Bondo]

Going to just order a switch and see what happens then thank you. Like you said we figured the source of the heat should be the source of the problem

Ayuh,...... Just by-pass it with a piece of wire,......

 

[Ryant10275]

Well i replaced the switch took it out last week only for about 20 minutes all was fine took it out today. Ran fine for 20 minutes or so. Parked in a cove to hang out had to start it up maybe two or 3 times to move from drifting in and ran fine then all the sudden same thing is happening again. It’s popping the rest switch at the key and not getting any soark