possible causes of a leak in the radiator system?

[Uncle Nick]

Could be increased pressure in your cooling system. Worst case scenario is a blown head gasket. Try first the cheapest parts. In order: radiator cap, clips/clamps, hoses, fans, radiator, thermostat, THEN head gasket.

There is one sure-fire way to troubleshoot this problem.

Do a pressure test.

You can borrow, rent, buy, or make a pressure tester which you screw on instead of the radiator cap.

Or go to a radiator shop and ask that they do a pressure test only, no repairs.

You pump up the pressure with the bulb and look for a leak...radiator, radiator neck, hoses, clamps, water pump (and gasket). Look on the ground for coolant.

See if the pressure on the guage has gone down or remained stable.

If you have a head gasket problem, you will see white smoke in your exhaust. Do a compression test to verify.

Replacing parts randomly according to price does not always work and can be more costly in the long run.

I'm sorry. I don't mean to discredit your suggestions, I just want to help.

Ciao!

Uncle Nick.