The sensor is the ground connection. You should only need a positive and the sensor wire. Have you taken an ohmic read from the sensor post to the engine block with the oil sensor wire off the post, this will see if the sending unit is good.Someone might laugh at me for this but I need help. I’m trying to get the oil pressure gauge hooked up so that I can test run this engine longer and be confident that I have oil for it. Problem I’m having is every time I hook up the ignition wire it peggs out the gauge. The way I have it wired is one wire to the sending unit which is just a single post. And I have a positive and a ground going right to the battery. I have tried two different gauges and they both max out as soon as I hook up the power wire.
Yes these gauges I have are that way. But I don’t have ground straps or anything hooked up. So this basically is like starting the engine on a stand. The battery is on the floor. But I’m not sure if it’s a sender or switch like you say. This was a generator motor.You might also get the same result if your "pressure sensor" is actually an oil pressure switch - The oil pressure switch is a direct short to ground at zero PSI oil pressure.
QUICK EDIT: Most electric oil pressure gauges are 3 terminal devices
S - wire to the sender
The electric oil pressure gauge MUST be used with a sender that has a matching resistance range. A quick Google search returned a few resistance ranges.... But I’m not sure if it’s a sender or switch like you say...
Makes me wonder what a stock bronco range is. I also wonder if I can take the oil pressure sending unit off my old 302. If the treads are the same.The electric oil pressure gauge MUST be used with a sender that has a matching resistance range. A quick Google search returned a few resistance ranges.
240 to 33 ohms
0 to 90 ohms
73 to 10 ohms
0 to 30 ohms
16 to 158 ohms
There are others - NOTE: Some resistance ranges are reversed from the others.
1. If you have the oil pressure sender that came with the electric oil pressure gauge, install it on the engine.
2. Buy a mechanical oil pressure gauge and install it (no electrical gremlins)
So I don't have another one on the passenger side. This one on the right in that pic came from the driver side but I couldn't see a part number on it. The on on the left is the original bronco sender. So I was thinking I will adapt it to work so I can use the stock oil gauge for the bronco. But it may also be a good idea to have a mechanical gauge pod.4bts sometimes came with both a pressure sender and a switch. Fairly common on industrial applications but was also found on engines in the delivery vans. Typically, the sender was located on the passenger's side of the block and the switch was over on the oil filter plate. However, my industrial 4bt manual shows a switch on the driver's side. Threads are listed as 1/8 x 27 NPTF.
Not that I know of. I upgraded the fuel pin and spring but I haven't done anything other than lower the idle bolt on the outside. This was a supposedly rebuilt pump off ebay. After I bump the throttle and it stays up a little if I shit the engine off and restart it, its back to normal.Has the fuel screw been adjusted on this pump? Sounds like you may be getting close to the run away point and need to back off on the fuel screw. If it should run away the only way to stop it would be cut off the air supply to the engine. Could get very scary.