Yanmar won't stop with the stop button

[ike70]

An interesting thing came up with my Yanmar 4LHA today - it will not stop with the stop button. Any ideas of how to locate the problem? The button feels mechanically OK.

Anyway, I think it' better this way than the other way around...

 

[David2452]

We had a similar issue with my friends Viki fitted with the same motor, he had to shut down using the stop arm on the pump by hand every now and again. It was the solenoid that had failed. They are a silly price but we managed to source one at a third or less of the Yanmar price as it was identical to an industrial one. If it turns out to be the solenoid I can ask him where we got it from as I don't recall now.

 

[Seahope]

An interesting thing came up with my Yanmar 4LHA today - it will not stop with the stop button. Any ideas of how to locate the problem? The button feels mechanically OK.

Anyway, I think it' better this way than the other way around...

I experienced that once in the winter when the electrics were probably a little wet and the boat wasn't fully mine. The solenoid triggered by the stop button just moves a wire to turn off the fuel supply. Very easy to stop by hand once you know where to look.

Possibilities - 1. electrical problem from switch to solenoid, 2. solenoid failure, 3. wire moved by solenoid loose.

I would get an engineer to look at it if I were you

 

[Searush]

With novice crew at the helm I discovered that my yanmar stop button doesn't work when the ignition is turned off!

Check connections too, there should be a wiring diagram with the engine manual so check the voltage/ earth conditions are as they should be when ignition switched on.

 

[ike70]

Thanks for the tips guys.

Can I test whether the problem is in the switch to solenoid or in the solenoid itself with a voltage meter? There are two wires connected to the solenoid. I assume that if there is voltage between the plus terminal of the solenoid and the minus terminal of the battery when the stop switch is pressed, then the problem is with the solenoid. Or should I test it some other way?

Forgive me the questions - electricity has never been my strongest competence...

 

[David2452]

Thanks for the tips guys.
I assume that if there is voltage between the plus terminal of the solenoid and the minus terminal of the battery when the stop switch is pressed, then the problem is with the solenoid.

Your assumption is correct, however just because there is voltage on the meter doesn't mean there is enough amps available to operate the device (corroded terminals, cable etc causing resistance) a better way is to make up a test lamp with a 20 watt bulb or use one from a shop, they are really cheap. I only say that because a solenoid is expensive and you really need to have a sure diagnosis, you may want to confirm by whipping it off and aplying power direct.

 

[Willyok]

HEy guys I am having this same issue. I have verified the solenoid is pulling the lever all the way, but its still not securing. I think the spring inside the pump is worn out because if I play with the stop lever it will shut down.

Any help is appreciated.

will