Trying to plumb a softtail oil tank to my shovelhead? Working fine before now builds pressure in the tank?

Don't worry about it Bro, put a lower pressure sensor on it. I've had guys crying to me that put a oil pressure gage on there Shovelhead, good pressure when first start up, after warm the gage goes to zero. Brutha, Hawg pumps ain't made to build pressure, just circulate oil is all they do. Your oil is circulating thru the engine now. Like I said, if your that concerned about it, replace the sensor.Safe trip Bro.

The motor on that unit uses a start capacitor and when that capacitor fails, the motor wont rotate, it just humms.

It should be on the left side of the oil tank, by the left side of the seat. The round oil filler cap should have a dipstick on it. Some are replaced with an optional oil temp gauge style cap with dipstick.

If in the past your system can build-up pressure up to 40 psi even if the supply valve is open and water is being used in your house, then your pump impeller maybe already worn out that's why its pumping capacity was reduced.

Is the pump building pressure and shutting off? If the pump keeps running but not building pressure than there is most likely a problem with the well (low volume). Also check for a water logged bladder tank.
RJ

The check valve is bad. When the system builds up pressure and shuts off the check valve prevents water from dropping back down the well line. When the check valve goes bad water drops back down the well line and siphons water back out of the well tank causing the switch to kick on and off constantly. The check valve will between on the well line coming from the drop pipe. It may be making a constant rattling noise as pump is running. Replace the check valve and you should be fine. Also check the pressure in bladder tank it should be 2psi below the "cut-in" pressure for the switch.
RJ

Check for a leak between you compressor head (pump) and your tank. Your pump output may be good but as your tank pressure gets higher the leak will not allow the tank to build up.

well, I've got no experience with TP oil pumps but I do have experience with S&S and Ultima. This is common on Shovelheads. When your engine gets hot, your gauge will show zero or very little oil pressure when idling. If you think you've got problems with oil, when it does this, pull the dipstick out of your oil tank and watch for the oil to swirl due to the return. The oil will look sort of "foamy" on top as well. Rev the engine a bit. This indicates that your pump is pumping oil.

A Harley engne uses a high volume low pressure oil system. The reason it won't hold oil pressure when hot is that the crank and the rest of the engine is constructed of roller or needle bearings. It doesn't have shell type babbit bearings like a *** bike. When a roller in the rod bearing rolls over the oil hole in the crankpin, you might build up a bit of pressure momentarily but very quickly, the hole is reopened and oil is squirting in between the round roller or needles. Take a dozen round pencils or something and place them side by side. Notice how much of the pencils touch the table, not much. The reason you get oil pressure when the engine is cold is because the oil is thick and the small holes it has to go through offer a lot of resistance when the oil is cold. When hot, the oil flows readily through the holes.

I assume you built your engine and used hydraulic units in the tappets like original or some other type of hydraulic tappet system. If you didn't have any oil pressure, the hydraulic units would be clattering quite loudly. Still the best way to check to see if your oil pump is indeed working is to watch for the oil return to the oil tank. Take the large oil filler cap off and remove the oil filter. Start the engine and watch for the oil flow. Do this with the engine hot.

Then throw that gauge away. You asked for a recommendation, that's it.

Ride Safe
Steve

try changing bulbs wiggle around see if comes on if not pull the assy from between the tanks and check wiring sometimes the sockets the bulbs sit in take a dump if youre inclined replace the sockets if not JP cycles and buy a new one with all new components