[iang]

I have a 1991 Yamaha 150 V6 which I have just rebuilt.I have removed the oil pump and wiring and on trying to set up timing and sync I found I have no spark.I do have a manual but there is no wiring diagram showing my ignition system which has a little black box labeled control unit just below the CDI unit.Can anybody tell me if the oil monitoring system has anything to do with some form of shut down of the ignition and if so,how can I get around it?If this is not a problem,then the test procedure,as far as I can make out,everything appears to be OK but the power is somehow going to earth.

[rodbolt]

without a model number can you tell me if this is a US market motor or overseas?
once we figgue out what motor you have we can help.

[iang]

Sorry about that,this is an Aussie motor assembled in Japan,I only know the year approx by the fact that the oil pump is vertically mounted.I have sorted out the spark issue,the ones not firing had oxidised bullet terminals to the coils,a bit of power tune and contact spray did the job.I still want to know if the control unit mountde below the CDI can be disconnected in some way.Thanks.

[rodbolt]

without seeing it I cant say much.
the US V6 motors until 1990 had the oil control module mounted below the engine oil tank and from 1990 the module was internal to the ECU assy.

[iang]

Thanks for your input,greatly appreciated.The module I am looking at appears to be connected to the temp sensor circuit and must be some early form of engine gardian,once I take the boat for a run I will know if there is a problem in this area.