Yesterday i was driving and i checked my temperature gauge, and it was almost at the top... a little higher than 3/4.... luckly i was almost home.. when i got home i opened the hood and noticed that the overflow canister was spraying some HOT water out, it seems to be having a leak.... could this be the problem??? or could it be the water pump??? is there a way to test if the water pump is fine??? I am not very familiar with the cooling system so i need some help..
thanks

 

check your thermostat follow the lower radiator hose to the back of the motor and there is three bolts remove the housing, replace thermostat and gastket, replace three bolts, fill coolant and your done

 

to check to see if the water pump is working, take off the radiator cap and warm the engine up (~185 *F). You should be able to look into the radiator fill hole and see the water flowing by as it comes from the pump, through the engine, and through the top radiator hose into the upper tank of the radiator.

Also, make sure your fan is working. One of the most common problems with D-series engines is that the radiator fan switch (brass switch with rubber boot on it, above the oil filter) goes bad.

Less common is the thermostat sticking. If it sticks closed, no cooling water can flow through the engine/head/radiator and cool the engine.

If your temp hand gets above the half-way line, turn on the heat full blast. If the air is cold you don't have enough coolant in the system. If the air is hot and the temp starts to decrease, most likely you either have a bad fan, fan switch, or a clogged radiator.

 

sounds like your thermostat or maybe even your radiator cap wnet bad and isnt holding pressure correctly anymore. i rescently had a bad radiator and i got a new one, and while replacing the hoses found i didnt have a thermostat at all. so new hoses radiator, radiator cap, thermostat and coolant. and now it runs like a champ and never goes above half way.

 

you might also want to try and make sure there are no air pockets in the cooling system somewhere....i had a similar problem thought and it turned out to be a clogged radiator.....any radiator shop can clean it out for you for around 50 bucks

 

yeah if its clogged you can get a cleaning kit from walmart and do it yourself and save the dough. and also clean the front off with the hose to make sure theres no dirty or leaves cloging the way for air flow.

 

damn...good call man....wish i had known that before i spent 50 bucks

 

check your hoses as well could be leaking pressure from there as well