454 - How many oil pressure / water temp sensors?

[mwilley22]

Hi again, we are wrapping up our 1988 Baja Project...and it has been a big project. We have the Mercruiser 454 mag 4 bolt main and have a water temp sensor in the water thermostat housing and an oil pressure sensor on the back of the motor by the oil filter. We have left over wires that our manual states the tan w/ blue line is for a water temp sensor and a solid light blue wire for oil pressure. Does the motor have add'l sensors that we need to purchase or are the ones we already have hooked up sufficient? How many oil pressure sensors and water temp sensors should the motor have on it?

 

[Don S]

Re: 454 - How many oil pressure / water temp sensors?

The blue wire is for your oil pressure gauge SENDER, the tan blue wires all go to alarm SWITCHES used for the audible alarm.
If you don't have the alarm switches for temp and low oil pressure, then the tan/blue wires won't be used. But you do want to hook up your blue wire to the oil pressure sender.