I have a 1997 Honda Civic ex 1.6l we've replaced all hoses and the motor was rebuilt 4 months ago but the top main radiator hose has alot of pressure and it has popped off the radiator it will over heat and the guage goes back to normal when the car is slowed down as Soon as speed gets back up the guage goes up we can't figure out what's going on with it could I have some input please thank you

 

We started replacing hoses when one busted on us and then another so we replaced all of them but now there is alot of pressure on the top radiator hose and we can't figure out why

 

compression test, leak down test and block tester test (blue fluid goes yellow)

 

Ok could you tell me why when we start it up and take the radiator top off the antifreeze comes pouring out of the radiator

 

That happens because the head gasket is blown or there is a crack in the head or the block. Air and exhaust from the cylinders blows through the leak and pushes the coolant out of the engine.

There should be no action in the radiator when you start the engine up cold with the radiator cap off. (Do not take the cap off while the engine is hot. Do this test only with it completely cold.)

 

Thermostat stuck shut? Bad radiator cap?

 

Ok thank you and we will have to change that out