Hello Community! I have a 1990 Combi cooled by water. The radiator is good, the thermoswitch is good and proven, the relays are fine, the 2 bulbs (red and black) that go near the head are new, the wiring is fine ... but when I turn on the combi, in 1 minute the temperature needle rises up to the top without giving chance to the water to heat the ventilator.
It has no thermostat, the water pump if it serves.
What else is left? The head of the head? How to check it without disassembling? What recommendation do they give me? Thank you in advance.