My bus overheat, why ?

[PB612]

Hi everybody !

So there is my problem of the day.

My bus overheat pretty easily, short uphill road, long ones, it’s not cool.

I’ve clean the radiator with a air compressor, I’ve drained it and put new coolant, my fan seems working, but it still overheating.

My bus is a 1996 Internationnal, 3600 Vista, it’s the short nose one.

I believe it’s a Navistar

Any thought one what could it be ?

[JackE]

Plugged radiator
Thermostat stuck closed
Bad fan clutch
Burned valves

Will it overheat idling, or just while driving?

[EastCoastCB]

Have you checked the water pump? Is it weeping, and does it have any excess play?
Check your thermostats?

How's your transmission fluid look?