K,
Two devices share (are OR'd) a common connection(it's just the negative power side of the DC beeper actually) on the terminal block (14) and either device can turn on the beeper by sending/issuing a ground signal(an active low).
1: The warning module(3), it can turn the beeper on for several reason, continuous with a solid low(low oil in reservoir sensor) or beep w an intermittent low(oil pump rotation sensor) or the infamous merc power up "I'm alive, functional and things(*so far) feel goooood alll over" triple beep when the module is first powered.
OR
2: The "water temp switch" (**15), when over heated, it sends a solid low as it is just a switch to ground when above somewhere's around 235'ish F(I'm not looking it up right now, but there is a spec)
So .....assuming the replacement water temp switch is good, and w a solid beep when stone cold
1: Your reserve oil tank(the tank one under the cowl) sensor(4) has activated due to low oil or went bad due to bad float and your warning module has then been told to issued a solid low causing the continuous beep(unplugging the oil float bullet connector at the input of the module will shut it off if the oil float sensor is the source)
or
2: The module output has shorted to ground[disconnecting the output wire (tan/blue)of the module that leads also to the(shared) over temp sensor connection at the terminal block will shut it off if the module is the cause]
or
3: You have a short somewhere to ground(a third unwanted active low..) on the shared line causing the continuous beep .........Ohm meter time.
*The module at first power up w/o the motor running comes online(triple beep) and is in standby, It won't send out an alarm low unless/until it first receives the "motor is running" signal from the CDI box(see grn wire leading to module)..If I recall right, for both inputs or was it just the pump rotation, I forgot, its been about a year since i messed w it!.....Never committed to memory or I'm simply just getting old...hmmmm,
**The schematic below has the wire color listed as "black" leading from the water temp switch(15)......This is a mistake, the wire color of the water temp switch is tan/blue.
