Bad Thermostat?

[e170drvr]

Wondering why my Oil temps are a little high. After warming the car up (87 930) at about the 8 o'clock mark on the oil temp Gage I believe the oil cooler lines open. When I check my oil it reads low until the oil temp reaches the halfway 9 o'clock point on my Gage then reads normal.

I went out and checked the front cooler, and it is indeed hot, however one line is blistering hot and the other is just warm (you can hold it without it getting uncomfortable. It seems that it is not warm enough to have even cooled oil passing through it.

Should I be looking at the external thermostat? sounds like it is not opening fully until the temp gets really high at which point my oil quantity reads normal as confirmed by the dipstick. Any thoughts?

Thanks,
Eric

[spuggy]

At my last oil change, it took a fair while time for the oil cooler return line to heat up, long after the oil temperature gauge is reading up to tempurate in the tank. Exactly as you describe. The return was stone cold for ages and suddenly went "oh yeh, that's hot" hot in the fender and gradually worked back.

Personally, I really hate letting the motor idle that long. Go and drive it hard for half an hour or so and then check the return line.

It's my take that until all the oil in the system - including the stuff in the cooler and the return line - is up to temperature, you shouldn't check the oil level - because you'll get a false reading (too low).