CLICK, trying to start. '91 Mercruiser 3.0

CaptOchs

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I've gone through the troubleshooting tips in the "adults only" section. Very helpful, but I'm still dumbfounded as to why my engine won't start.

My wiring scheme sounds different from the troubleshooting guide so I'll just go by my layout on the starter solonoid.

Plug A is the big kahuna. This terminal has the Positive battery wire. There's also an orange that goes to the alternator. The alternator also has another h heavier guage red wire that ends up at this terminal. That red wire has an inline 50 amp circuit breaker.

Plug B is a short heavy wire that goes right to the starter.

Plug C goes to a yellow and red striped wire to what looks like a safety switch.

Plug D is a purple & yellow wire that goes to the coil.

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

I have a test light and multimeter I used to test everything. Terminal A has power on always. I traced juice back to the alternator first by checking the orange wire. I also followed the red wire, testing both sides of the circuit breaker to the alternator. Everything seems good.

I hooked my jumpstarter backup battery to Terminal B (starter) and connected the negative to the ground. The engine turned over. This rules out a faulty starter.

Terminal C is only hot with the ignition starting. It goes to what looks like a safety switch. On one side, the yellow/red stripe (from terminal C) connects to one end and another yellow/red stripe on the opposite side goes into the wire bundle and disappears. I tested both sides of the yellow/red wires and verified power. The other side of the switch is sort of a mystery. There's a red wire (from the bundle) one one end and a black on the other. The red wire has power, the black does not. Not sure if that's by design.

When I hooked my light testor to Terminal D, the light bulb was weak with the ignition in the on position. Once you turn the key the light testor was bright. The purple/yellow stripe wire leads to the coil, (which has power.) The terminal on the coil also has an unknown brown. The other terminal on the coil has a black leading to the lower part of the coil and a brown wire that is grounded to the engine.

I'm wondering if this saftey switch is throwing me off. That or perhaps the solenoid is truely faulty. Did I miss anything? I really couldn't find the neautral switch.

To all of the captian obviouses out there: both batteries I tried are good. I also cleaned all my connections so they look brand new again. I know the starter works because my jumpstarter (which has far less amperage) turned the engine over.
 

Don S

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Re: CLICK, trying to start. '91 Mercruiser 3.0

My wiring scheme sounds different from the troubleshooting guide

Where did you get YOUR wiring schematic? What manual, what page, post a picture. We can't help if we dont know what you are looking at.
 

stonyloam

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Re: CLICK, trying to start. '91 Mercruiser 3.0

Plug C goes to a yellow and red striped wire to what looks like a safety switch.

I believe that is the slave solenoid. Try this: Pull the center wire out of the distributor (so we don't get an accidental start). Ignition switch off. Jumper from battery (big red wire) to y/r wire terminal on slave solenoid, the one that goes back to starter. Motor should turn over. If it does, next jumper battery to the r/y wire going into the slave solenoid. The starter should run, if just a click you probably have a bad slave solenoid. If it runs, you have a problem with the wiring to the ignition switch. I think that is right:confused:. anyway good luck.
 

CaptOchs

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Re: CLICK, trying to start. '91 Mercruiser 3.0

I believe that is the slave solenoid. Try this: Pull the center wire out of the distributor (so we don't get an accidental start). Ignition switch off. Jumper from battery (big red wire) to y/r wire terminal on slave solenoid, the one that goes back to starter. Motor should turn over. If it does, next jumper battery to the r/y wire going into the slave solenoid. The starter should run, if just a click you probably have a bad slave solenoid. If it runs, you have a problem with the wiring to the ignition switch. I think that is right:confused:. anyway good luck.

I was thinking that too. However, I took the starter to a marina on my lunchbreak and he said it looked like it was submerged at one point. I think I'm going to have the starter rebuilt now rather than wait for it to get worse. If rebuilding the starter doesn't solve the issue, I'll know what to look at next. It's a new-to-me boat. It has become apparent this guy didn't take care of this boat at all.
 

Fishermark

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Re: CLICK, trying to start. '91 Mercruiser 3.0

Plug A is the big kahuna. This terminal has the Positive battery wire. There's also an orange that goes to the alternator. The alternator also has another h heavier guage red wire that ends up at this terminal. That red wire has an inline 50 amp circuit breaker.

Plug B is a short heavy wire that goes right to the starter.

Plug C goes to a yellow and red striped wire to what looks like a safety switch.

Plug D is a purple & yellow wire that goes to the coil.


Something doesn't make sense.... :confused:

Are you describing the solenoid on the starter, or the slave solenoid?

If you are describing the starter solenoid... then Plug B doesn't make sense.


If you are describing the slave solenoid... then Plug A doesn't make sense. The battery cable should go directly to the starter solenoid, not the slave.
 

CaptOchs

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Re: CLICK, trying to start. '91 Mercruiser 3.0

Something doesn't make sense.... :confused:

Are you describing the solenoid on the starter, or the slave solenoid?

If you are describing the starter solenoid... then Plug B doesn't make sense.


If you are describing the slave solenoid... then Plug A doesn't make sense. The battery cable should go directly to the starter solenoid, not the slave.

The solenoid on the starter... Plug B is the terminal on that solenoid that connects to the starter. The cable is a couple inches long because the starter and starter solenoid are mounted on the same bracket. It's the 4th terminal on the solenoid more or less.

Did you see the link above under "mercruiser fans..." My system is the 3.0L Engine Wiring Diagram (Breaker Points Ignition) on page 4. The wire colors match what I've described. Before finding this, I didn't know about the slave solenoid.
 

fishrdan

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Re: CLICK, trying to start. '91 Mercruiser 3.0

I believe that is the slave solenoid.

I think you are right, he needs to find the slave solenoid.

From what I'm reading, I had the same problem last weekend, ran around for awhile with the engine starting fine,,, and then click, click with no starter engagement... &*#(^

To troubleshoot I bypassed the slave solenoid with a short piece of wire held on the starter solenoid's yellow/red wire and the slave solenoids red/(?purple?) wire. (In hindsight I could have just jumped across the 2 big studs on the slave solenoid, just make sure you don't touch the threaded portion of the studs as arcing could mess up the threads) The starter turned over and I found that the slave solenoid wasn't working. It was actually a loose connection inside the slave solenoid since I was able to get it working by take all the wires off the slave solenoid, tightening the nuts and then reinstalling all the wires.

Even though I got the slave solenoid working, I'll be replacing it since there is probably some damage inside the solenoid caused by acring across the loose connection,,, inside the solenoid.
 

Fishermark

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Re: CLICK, trying to start. '91 Mercruiser 3.0

I did see your link, yes. Plug B is still curious. I've just never seen a wire there. Even the link you shared (which is nice by the way) doesn't show a wire - it is more of a bolt / copper sleeve hard wire connection.

And, no offense, but I don't see how you could've looked at the troubleshooting link posted by Don and say you didn't know about a slave solenoid. :confused:
 

CaptOchs

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Re: CLICK, trying to start. '91 Mercruiser 3.0

FishrDan:
Your issue sounds exactly like what I'm having. It seemed like a low battery situation because it seems to randomly work. To quote : I tested both sides of the yellow/red wires and verified power. There's a red wire (from the bundle) one one end and a black on the other. The red wire has power, the black does not I think I just mis-identified the slave solenoid as a safety switch. Given that, I think my slave solenoid is OK because both sides of the yellow/red wire checked out and the red has power. The black is a ground. I'm betting my (master) starting solenoid is shot.

FisherMark:
The PDF doesn't show a good closeup of the terminals on the solenoid. Some solenoids very well could be wired directly to the starter. Mine still has a 4th terminal and a short wire connecting them.
I take no offense. I've always been an outboard guy and I've never heard of two solenoids before this. I thought it was the neutral safety switch, thats all. Don's thread seemed generic enough that I wasn't sure it was 100% accurate for my motor. I think I'm done buying manuals. I found better info online for free. lol.
 

Fishermark

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Re: CLICK, trying to start. '91 Mercruiser 3.0

I take no offense. I've always been an outboard guy and I've never heard of two solenoids before this. I thought it was the neutral safety switch, thats all. Don's thread seemed generic enough that I wasn't sure it was 100% accurate for my motor.

Very good! :cool:


I think I'm done buying manuals. I found better info online for free. lol.

That's definitely true - you can get the complete manual at the top of the page.
 
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