Help! What is this?

[tank1949]

I bought an older SR Amberjack that has been retrofitted with Mercruiser Bravos and 383 Strokers with Thunderbolt 5 ignitions. The AJ has had 4 or 5 owners over lifetime. Past owner couldn't identify what is in photo. I believe it is a motor audio alarm? I believe person who installed TB5 ignition disconnected it, but I am really not sure. If anyone has schematic of what wires go where, please provide. There also appears to be two three wire plugs (assume alt. oil and heat switches), but I am not real certain how they connect. Help!

 

[jimmbo]

Warning horn for oil pressure, water temp is my guess

 

[muc]

That's the controller for engine synchronizer gauge. It is usually a 2" gauge that is usually between the tachometers and tells you how close the engines are to each other in RPMs. Under the red plug will be a slotted screw to adjust the gauge. Might find a wiring diagram on the Teleflex website. I think all the newer sync gauges have the circuitry built in them.

 

[tank1949]

That's the controller for engine synchronizer gauge. It is usually a 2" gauge that is usually between the tachometers and tells you how close the engines are to each other in RPMs. Under the red plug will be a slotted screw to adjust the gauge. Might find a wiring diagram on the Teleflex website. I think all the newer sync gauges have the circuitry built in them.

Sorry, I didn't get back to u sooner. I have been replacing rot that a so-called qualified marine surveyor missed. Boat came with Flomaster and its sync. At least now, I know what original MC sync device is. THX!