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Which 115hp motor do you have?
Most all electrical gauges work the same way. They require power coming from the key switch to turn them ON (Purple wire). Also require a ground (Black wire). There can also be a wire to light the gauge up at night.
Last is a sensor wire and will vary in...
Take a white or light colored rag and feel along the HP hose to see where the fluid shows up
You can wipe the rag over the unit to see if any oil shows up
There is nothing abnormal about hearing a clunk from the gears, there is a small amount of space between the gear teeth. When running you should only hear noise when going in and out of gear
Wish I had something to offer, but like you I'm lost to what could be causing it
I might be thinking about opening the box with a dremel to look inside
Or start following wires out to see if they are also getting hot and where ever they go is also
Things are not adding up. There is no reason that the relay should get even above warm unless something else has been added to the circuit.
You say even the area next to where the 40Amp fuse is getting hot.
That being the case, need to get in behind it to see what is causing that
We went in to the problem assuming the fuses were the correct size, and this seams we should have asked that question first. The FP fuse should be no larger then 20Amp
If fuse is larger then one or both of the pumps is drawing to much current
I meant to say with motor running
Red meter probe on Red/yell and black meter probe on red/purple
You can replace the connector by cutting the wires and solder splice to new connector.
Having issue trying to find the connector, but could always replace it with the standard square type
The relay should no more than the temp of the air. The relay can handle more current than what's called for by the fuel pumps
Place voltmeter probes between Red/purple and yell/red wires on the relay pins. You should see close to zero volts. The more resistance the higher the voltage
