Transmission Cooler Lines and Oil Pressure

Since I replaced the radiator, the transmission cooler lines needed to be removed. I dunked these in the ultrasonic cleaner to get the grunge off.

One of these lines is not like the other! A line was made from a converted brake line. The rubber of that hose was all gummy and starting to fall apart. I ended up replacing it with some barb fittings and a piece of transmission cooler hose.

I noticed while running the engine, that the oil pressure gauge never seemed to move once running. It was sitting at ~30-40lbs of pressure. I read on Porsche 924 forums that the oil pressure of these engines is supposed to be high. Looking in the service manual we have.

Cold idle should be around 100 PSI! 30 is much too low. But before figuring out if there was an oil problem or bearing problem, lets just check the gauge and sender. The gauges on this jeep are old and probably way out of calibration.

Measuring the sensor off the back of the engine with a multimeter I was reading ~140ohms at cold idle. The service manual has a way to calibrate the oil pressure gauge and specifies two points.

So 140ohms would be around 110psi. Looks like the engine is happy with oil pressure! Will have to figure out what is up with the gauges. I am betting that the ground for the dash has a bad connection.

It ended up just being some dirt in the gauge preventing the needle from moving.