No power to Yanmar ignition. SWMBO turned off using key instead of button

[sealegsjim]

There is no power to the ignition panel and I have been trying to find the fault. As we are on holiday for a few days in this glorious weather I have no test equipment with me and so it is proving rather difficult to figure out. In the last hour my wife has just 'fessed' up that she turned off the engine using the key last time we were here instead of using the stop button. Could this be the cause? and is the ignition system fused. I can't find anything obvious. I have loads of battery power so this is not the cause. Please help or holiday ruined!

 

[mtb]

do you have a length of wire and a bulb, you could use it to test for power. As a test you could hot wire the starter to get the engine running
My guess would be the stop solenoid
which engine do you have I can look for wiring diagram on line

cheers
mick

 

[sealegsjim]

do you have a length of wire and a bulb, you could use it to test for power. As a test you could hot wire the starter to get the engine running
My guess would be the stop solenoid
which engine do you have I can look for wiring diagram on line

cheers
mick

It's aYanmar 2GM 20F Thanks for reply

 

[mtb]

theres a 30amp fuse trace the ( looks like red but could be white ) wire from the key switch to the starter motor it also connects the alternator with a red wire

 

[mtb]

if you can receive an email I could send you the diagram

 

[VicS]

theres a 30amp fuse trace the ( looks like red but could be white ) wire from the key switch to the starter motor it also connects the alternator with a red wire

The fuse in the red wire from the starter seems to refer to panels that do not have a stop button are you sure it applies to the OPs engine

Other panels ( with a stop button) have a 3amp fuse in them which protects the warning lights and tacho. AFAICS its failure would not affect the starting and stopping, just the lights buzzer and tacho

 

[mtb]

no I'm not sure but the 30amp fuse follows the general format on all the diagram's I have. The diagram doesn't show a stop how ever they can be added but I'd still be checking for the fuse in this case

 

[sealegsjim]

The fuse in the red wire from the starter seems to refer to panels that do not have a stop button are you sure it applies to the OPs engine

Other panels ( with a stop button) have a 3amp fuse in them which protects the warning lights and tacho. AFAICS its failure would not affect the starting and stopping, just the lights buzzer and

tacho

There is a fuse in the panel but looks OK unfortunately

 

[mtb]

check down near the main battery switch a 30amp fuse will have a large holder because of heat nothing will light up if the main fuse has gone

 

[sealegsjim]

check down near the main battery switch a 30amp fuse will have a large holder because of heat nothing will light up if the main fuse has gone

Found a fuse next to the battery switch but it is OK. Everthing else on the boat works fine - lights/fridge/bilge pump/nav lights etc just no power to the ignition switch

 

[VicS]

Found a fuse next to the battery switch but it is OK. Everthing else on the boat works fine - lights/fridge/bilge pump/nav lights etc just no power to the ignition switch

Going to have to systematically check the wiring and its connectors between the battery and the ignition switch then.


A test lamp on a couple of leads is often better than a multimeter. Multimeters take so little current that they will give a " normal" reading even through a bad connection

 

[sealegsjim]

Going to have to systematically check the wiring and its connectors between the battery and the ignition switch then.


A test lamp on a couple of leads is often better than a multimeter. Multimeters take so little current that they will give a " normal" reading even through a bad connection

I'll try that tomorrow . Thanks

 

[onesea]

Now to check the obvious, do you have a separate starter battery?

I know on my boat if I had flat engine battery my only clew would be the Symptoms you describe... I have a separate starter battery and a solely domestic battery...

The only thing linking the two is the split diode for charging....

 

[VicS]

I'll try that tomorrow . Thanks

Dont overlook the possibility of a bad connection on the negative.

 

[Searush]

I'm pretty sure I turned the key off on my Yanmar 3YM30 once or twice with no known ill effects. It sure as hell didn't stop the engine tho . . .

Don't be so quick to blame SWMBO, be methodical & work thro the basics bit by bit until you narrow it down.

 

[sealegsjim]

Now to check the obvious, do you have a separate starter battery?

I know on my boat if I had flat engine battery my only clew would be the Symptoms you describe... I have a separate starter battery and a solely domestic battery...

The only thing linking the two is the split diode for charging....

The two batteries are wired in parallel. Just an on/off switch

 

[Searush]

Has the wire come off the back of the ign switch? Is there a relay in the circuit? Start at the switch & work your way back to the battery & I'll bet you'll find a break somewhere.

 

[sealegsjim]

Has the wire come off the back of the ign switch? Is there a relay in the circuit? Start at the switch & work your way back to the battery & I'll bet you'll find a break somewhere.

Connections are fine to the ign switch and I don't think there is a relay in the circuit. Thanks for the encouragement. I'll keep trying but it is bloody hot down there

 

[BlueChip]

You can't stop a Yanmar diesel by turning the ignition switch off, however the stop solenoid will only work with the ignition turned on.

 

[Bobobolinsky]

Screwdriver the starter to see if it turns over