1HDT Cooling System help

[Jacko]

Just after some advice regarding the cooling system on the 80 series 1hdt engine.

Had a leaking radiator the other day, so have replaced that.
New radiator seemed to have a slight leak initially, but that has now stopped.
What I can't figure out, is after having gone for a quick drive up a hill to test everything out, the lower coolant hose from the radiator is still cold, while the upper coolant hose is hot. The temp guage showed a normal temperature approx 1/3 - 1/2 way up the gauge. Also the heater is pumping warm air.

I'm wondering now whether I might have a faulty thermostat? Or maybe it simply takes a long time for the 1hdt engine to get hot enough for the thermostat to open?

Any suggestions much appreciated.

[cornfarmer]

How's the water pump? If you think it's still leaking pressure testing can be good insurance.

[Jacko]

yea was going to replace the thermostat then get the system pressure tested. how would i test if the water pump is working or not?