92 Nissan Sentra overheating probs

92 Nissan Sentra overheating probs
Highway driving to work and back on a regular day and city driving for hours, never give me any overheating problems.
Went on a 2-3 hour drive in the country, it was a hot weekend +29-31 (Celsius. When ever I went more then 110Km/h I would start over heating. If I cranked the heater I could run at 130Km/h without overheating.

I just had the water pump replaced, they put on a new radiator cap and hoses at the same time, the car is black (if that makes a difference), both the radiator fans are working and the hoses are hot so I'm thinking that it's not the thermostat.

Any help and diagnosing tips would be greatly appreciated:)

-Dougie

  AofI

1 low antifreeze level or air bubble/pocket=top up system
2 bad thermostat or wrong heat range=replace with new one of proper heat range from the dealer(i dont like the universal types from the parts stores)
3 crap in cooling system plugging tubes in the rad=have the cooling system flushed

  osborste

Antifreeze is good, but I'll look into the heat range on the thermostat. I didn't even think that there might be different ones. When I had the pump replaced would they not have flushed the system? Is this somthing I could do my self with basic tools and and air compressor?

Thank you for the help:)
-Dougie

  AofI