Yanmar low voltage alarm

[bakerboat]

Hi Everyone,

We have a Yanmar 4BY2-180 in our 2013 R27 and recently had the low oil pressure fix done. That seems to have corrected that problem but today we were getting very intermittent low voltage alarm at varying engine speeds (sometimes so quick, you couldn't read the message). I don't know if it is related but I thought I would ask the group if they had seen this occurrence. I would suspect it is a bad/corroded connection somewhere and was hoping some one might point me in the right direction as to where it might be.

Many thanks in advance.

Ken
R27 O'Meara
Arrowsic, Maine

 

[doke01]

I have a Yanmar 4JH3-DTE so not sure if the symptoms would be the same but there is a two wire connector to the back of the alternator that had become corroded and displayed similar symptoms. The actual terminals were corroded to almost nothing and the alternator had to be replaced.

 

[captstu]

The local Yanmar dealer just did the oil pressure fix on the Shearwater's 4BY2-150. Or they did 1/2 of it. The ground wire must be changed at the same time the software upgrade in applied to the controller. On the Shearwater, they did the software upgrade, but not the wiring change - resulting in the problems you describe.

The service advisory from Yanmar describes how to tell in the wiring was repaired at the same time - the two wires on the oil pressure transducer are marked with a number code before the fix - and only one is marked after the fix. Most likely, this is the problem you are seeing.