By January 10, 2013 0 Comments Read More →

Upper Radiator Hose Blew Up

Reader Question


Hi…i have a 99 Nissan Frontier 2.4 2WD. Replaced the water pump (leaking, the thermostat, & the radiator cap.  Still overheating.  Idling after it sits for 30 minutes, it stays cool, but within 5 minutes of driving overheats. There is a lot of pressure on top hose.

I was trying to get into a parking lot, heard a big boom….the top radiator hose EXPLODED!! It literally blew a chunk out of the hose.  No water in oil, does have a little white smoke..blown head gasket, I am assuming.

Going to try the K&W Seal in the morning. Also heat never blows hot, going to blow out those hoses & heater core. Any suggestions on what it could possibly be? Spent way to much money already & can’t really afford the coolant test. Appreciate you in advance


Hi there


I was about to go to sleep….but.

Usually when the upper radiator hose swells up its due to a bad radiator cap that is not venting properly. Make sure the cap you replaced is the correct one for your vehicle.

Second thing, check upper and lower rad hoses when engine is at normal temperature, they should be the same temp.

If there is no hot air out heater then there is not enough coolant in radiator or there is a restriction somewhere like inside the radiator not allowing coolant to flow.  Radiator replacement is the answer, flushing does nothing.

Austin Davis

Posted in: Over Heating

About the Author:

Austin Davis, consumer car repair advocate. "Hi there! I love to help people solve their car repair problems and I hope my site was helpful to you today. Thank you for stopping by."