I have an oil leak coming from the area of the oil cooler. How can I determine if its the cooler itself or just the seals?

Before you worry yourself about the cooler, check the oil pressure switch. It's under the tin, right beside the distributor. Common poroblem. If it's good, then you may have a cooler or seal leak. Leaking seals are rarely the problem, and you have to remove the fan shroud to get to the cooler itself (some say they've changed the cooler seals in the car, but I wouldn't waste a whole day doing that). The cooler can be pressure tested with a proper test rig. Good luck! The Cap'n

follow the advice of the Cap'n. but if it is the oil cooler seals, they can be replaced with the engine in the car. PIA but it didn't take me a whole day to renew them either.

Oil leak?

No!

Its supposed to do that.

OK I'm kidding, but in our cars oil is like, "You can't fire me, I quit."
If your 914 doesn't leak oil, you better check the oil pump.

Its got to be the oil cooler or seals b/c it does not leak until it gets warm and the t-stat opens.

My oil pressure control valve screw was seeping. I thought it was maybe the oil cooler seals, but when I got directly below with a flashlight, I found it dry below the oil cooler and then down as far as the cap. Very easy to replace, especially compared to either the oil cooler seals or resealing the pressure switch. Also, it would tend to leak more when the oil heats up and the plunger moves down to divert oil to the cooler, like in your case.

Just another thought....

There is no thermostat to control oil going through the oil cooler on a stock Type 4.