mazda b2600i over heating

ya thanks guys i found out what the problem was there was no problem i found out that the new thermostat opens once it hits a certain tempature the truck was over heating when i bought it so i had the head machine and cheacked out had replaced the headgasket and a new thermostat and some new fluids but when i took it out for a run on that hot day the tempature gage went really high and i wasn't exspecting that so i thought it was still messed up ,but today i took it for a run the tempature went high but when it hit a certain temp the thermostat opened and the truck went back to normal so if anyone ever have this problem check to see what kind of thermostat is in your truck i guess all trucks are different because i've never had that problem with any of my bseries truck i guess you learn something every day thanks guys for responding.

That thermostat is opening too late.
One of these days, it may open when it's already in the red zone.
Better replace it now with a colder thermostat since summer is still a long ways to go.
Mazda heads are prone to warp and crack when overheated. Good luck.

if you've run it hot- consider it done