2004 Radiator Hose Blew Off

[samIam]

I have 04 with 107K miles. Last week the bottom radiator blew off from the radiator luckly next to my driveway & the engine did not overheat, but the VSC Trac Control light came on, no check engine light. I put a new camp on & the next day after driving 45 miles this time the top hose blew off, again did not overheat. I used a NAPA kit to measure if exhaust gas in the cooling system & no gas was indicated. Took it to my mechanic & he checked the engine & said the head gasket is OK, but the pressure in the cooling system is too high. He is trying to figure out the problem.

The only work that has been done except for fluid changes & brakes is the water pump & radiator were replaced 8k miles ago (both leaked at the same time). Also it is a sport & the shocks were replaced at the same time. Has anyone seen this problem? Thanks

 

[banzaj]

Try replacing the cap first and see if it helps - they're cheap and I heard they should be replaced at some point or at least checked for performance. Also, just a guess, what if you have a leak in the system and as a result - lower than normal level of coolant and at the same time the radiator for some reason can't suck in more coolant from the reservoir tank to compensate (overfill (bypass) hose broken/ clogged/ not connected properly after your radiator replacement?), hence you see normal level in the tank but there's air in the system causing higher than normal temperature and pressure? Try taking the cap off the radiator when engine is cold - you should see the coolant right at the top, if not - top up. Also, check the level in the tank on cold and recheck it on hot - you should notice a 1 - 1,5 inch difference. Ask your mechanic to check for air pockets although this probably was the first thing he did. Anyway, it's good to know the OEM hoses are strong enough not to break but just to jump off the tubes.

Also, did you install OEM radiator and water pump?

Please, let us know of the solution when you find it.

P.S. Just found this: http://www.toyota-4runner.org/3rd-gen-t4rs/89608-radiator-upper-hose-question.html

 

[samIam]

The thermostat & radiator cap were replaced. My mechanic measured the hydrocarbons in the radiator & the test was negative. Also he scoped the cylinders & they look OK. Also the waterpump was from Toyota.