Bukh 36hp electrics

[1corinthian]

I am having problems with the warning lights on the instrument panel . Charging light illuminates in alarm position but not temperature or oil pressure lights . I have replaced the ignition switch as it has been temperamental latterly . When I turn the key the instruments power up . I am now starting to suspect a fault in the board to which the warning lighs connect .
The board has diodes and resistors on it . Does anyone have experience of this .

 

[robertj]

do you have block connectors?

 

[1corinthian]

Yes , two one red one blue .

 

[robertj]

start looking there for the start.
Have you had any water around the engine bay that could get on the main plugs if so, dry them out and spray with a water repellent the re connect and see what that does.
Ring Norm from Bukh UK he is a wizard on these engines.

 

[dolphin]

check all the connections of the cables coming out from the engine and going to the panel
i have had the same alarm warning light on and it was from not a good connection of the cables
also when i start the engine on low RPM the warning light is on and after increase the RPM is going off,
in returning back to low RPM the light is off

 

[VicMallows]

Very likely to be the circuit board. Probably corrosion. Just remove it and give it a good clean. Better still rewire the panel and alarm in a more straightforward manner without the resistor-diode logic.

 

[1corinthian]

Thank you everyone for suggestions . I have had the engine running today , first time since end of October . I have cleaned up the earth connection on the block and checked out and cleaned the 2 multi plugs .The engine instruments work fine together with the alternator/charge warning light and the audio alarm . I cannot get the oil pressure or temperature warning light to operate on the stop / warning lght / key switch position . I think it is related to the diodes and resistors on the junction board .I have removed it and cleaned the connections to no avail .I have a friend who may be able to fault check the board and I will phone Bukh UK for advice tomorrow .

 

[1corinthian]

An update on progress or lack of it . The problem appears to be related to the circuit board in that the three standard diodes will allow current flow both ways . I have attempted to replace the faulty diodes but my soldering ability is such that I have fried two of them . It looks like time for a new board . However for the longer term Vic M you mentioned a rewire to do away with the diode/resistor logic , does it still test the lights at switch -on . Do you have a diagram you could share with me .