Outer Limits 4x4 Board

G'day guys.
my 88 petrol hilux is overheating only when i 4wd. (temp needle in the red)
When I'm city driving the temp needle stays half way and seems cool.
But after a long drive i stop and i can hear the radiator bubbling over.. and the motor smells a bit to hot for my liking, even tho the temp needle indicates normal temps...

i have replaced radiator, radiator cap and thermostat. Its got pressure in all the pipes..

Why is it running hot?

The head is ok, im not using any water...
My only thought is the water pump? how much do they go for? easy to replace?

1st thing i would do if it was me is get rid of your current temp guage get a capiliar guage (mechanical type NOT ELECTRIC) put this in and see what happens.


You can check if your water pump is not working by WHEN COLD or CAREFULLY remove radiator cap when hot (dont want you to get burnt) start your engine and look in the top of your radiator and you should see your water level moving if it is then its working.