Mercruiser 3.0 not starting

[mucca21]

Hi, I have a 1999 3.0 Mercruiser which is not starting, you turn the key and nothing happens, not even a click from the starter motor. The battery is absolutely fine, so its not that. I have had a fiddle with it and have bridged the terminals on the solenoid which did turn the engine, this had lead me to believe it could be the solenoid. What do you think?

I have tried to remove the starter to get at the solenoid, but it seems to be the most awkward job in the world!! I couldn't get my socket on the inner-most bolt for love nor money!

Any ideas....

 

[TrybalRage]

Re: Mercruiser 3.0 not starting

Check that it's not the ignition switch. Mine wasn't working well enough anymore and had to be replaced even though it tested fine for continuity. Take it off and touch the wires together, see if it turns over.

 

[mucca21]

Re: Mercruiser 3.0 not starting

Having read up a bit more on my current issue, I believe it could be the ignition switch (thanks for pointing me in that direction TrybalRage!).

As I said before you turn the key and nothing happens; no guages flicker or anything. Yet the tilt/trim still works fine, so I'm assuming that that works independantly of the ignition switch? And this confirms to me that the battery is ok.

I have tried the testing described in one of the 'sticky' posts, and the ammeter which I borrowed didn't give a reading anywhere!

 

[TrybalRage]

Re: Mercruiser 3.0 not starting

If you can get one go with a marine ignition, they will be built better for moisture. However, I'm a cheapskate and threw in one I got at an auto parts store for 12 bucks. Simple 3 wire switch, make sure you get the right kind.

 

[mucca21]

Re: Mercruiser 3.0 not starting

I have got one through my local Mercruiser agent, so have paid a fair bit more than that! It was around ?50 so hopefully that will fix my problems, if not I'm really stuck!

 

[Silvertip]

Re: Mercruiser 3.0 not starting

Before you go through the trouble of replacing the ignition switch, use a "voltmeter" not an ammeter, to measure the voltage on the small terminal (the start terminal) on the solenoid while someone turns the key to START. If you measure 12 volts (battery voltage) on that terminal the ignition switch is NOT the problem. If you jumped (bridged) that terminal to the large terminal on the solenoid that has the battery POS cable attached to it and the engine now turned over, that would lead to either the wiring harness or the ignition switch. If there is a large connector in the engine bay, check it for corrosion. Simply disconnecting and connecting it a few times can burnish the contacts to bring the circuit back to life.

 

[Glastron175]

Re: Mercruiser 3.0 not starting

I had the same problem on my Volvo Penta 3.0. Had voltage at the solenoid, but would not turn the starter at all. Took of the starter and had it rebuilt. The brushes were all coroded and not making contact.

 

[mucca21]

Re: Mercruiser 3.0 not starting

Before you go through the trouble of replacing the ignition switch, use a "voltmeter" not an ammeter, to measure the voltage on the small terminal (the start terminal) on the solenoid while someone turns the key to START. If you measure 12 volts (battery voltage) on that terminal the ignition switch is NOT the problem. If you jumped (bridged) that terminal to the large terminal on the solenoid that has the battery POS cable attached to it and the engine now turned over, that would lead to either the wiring harness or the ignition switch. If there is a large connector in the engine bay, check it for corrosion. Simply disconnecting and connecting it a few times can burnish the contacts to bring the circuit back to life.

I was using a voltmeter, but not at the solenoid terminals; at the ignition switch terminals. The other thing that has lead me to believe it is the ignition switch is that nothing else comes on (fuel guage, lights, etc.) when you turn the switch to the first position, would this still be the case if the problem was something other than the ignition switch?

 

[TrybalRage]

Re: Mercruiser 3.0 not starting

Did you try and just remove the existing switch and touch the bare wires together? That should pretty quickly tell you if it is a switch issue.

 

[mucca21]

Re: Mercruiser 3.0 not starting

Ok...I've now replaced the ignition switch and the boat still won't start. Which now leads me to believe it could be the neutral cut-out switch. What do you think???

Also, is the neutral cut-out switch situated at the throttle controls or within the engine compartment on the gear linkage?

 

[Don S]

Re: Mercruiser 3.0 not starting

Have you looked at this thread yet?

http://forums.iboats.com/showthread.php?t=167035

 

[Borchik]

Re: Mercruiser 3.0 not starting

do you have a safety lanyard that is not on?

 

[Don S]

Re: Mercruiser 3.0 not starting

do you have a safety lanyard that is not on?

The kill switch lanyard will not keep the engine from cranking, or the gauges from working. It only kills power to the coil.

 

[mucca21]

Re: Mercruiser 3.0 not starting

Have you looked at this thread yet?

http://forums.iboats.com/showthread.php?t=167035

Yes, I followed it to the letter! Except, I had an ammeter instead of a test-light.

 

[Don S]

Re: Mercruiser 3.0 not starting

Yes, I followed it to the letter! Except, I had an ammeter instead of a test-light.

Try it with a test light.
First you shouldn't be using an "Amp" meter, you should be using a "Volt" meter, and with that it makes me wonder if you know how to use a VOM properly. Use it wrong and it's hard to tell what you see.
With a test light, you either see a light or not.

 

[mucca21]

Re: Mercruiser 3.0 not starting

After all that, it was a corroded wire that had shorted a fuse. So nothing too costly.