Water Pump?

[J.S.]

Whats up all? I have a 92 Grand prix(3.1). This morning I woke up to a cracked radiator and am trying to get some opinions about whether or not my water pump and thermostat was affected. The crack is a more like a scratch but my question is if I poured antifreeze into the radiator while the car was running and it threw it back up would that mean the water pump and thermostat are shot? Thanks

[GTP Dad]

No, excessive air in the system probably caused the antifreeze to come back at you since the thermostat was probably closed. Try running the engine until the stat opens and then put more antifreeze in it. Make sure the radiator is full before you start and when the level drops the stat is open. Then refill as needed to top it off.

[J.S.]

Gotcha. But is there some way to know if you need a water pump or not. I got a new radiator today but I'm thinking that running the car, even though not for extended amounts of time, hot, the water pump could be broken.

[richtazz]

No, the radiator and running the car hot for short periods will not hurt the water pump, but since you're replacing the radiator, it would be a good idea to change the t-stat while you're at it. The only thing that usually goes bad on a water pump is the shaft bearings and it's seal. The pump will start to leak out of the weep holes cast into the body of the pump near the bearings, indicating seal failure. If the water pump bearings are bad, it will cause the pulley to wobble or make noise. The only other issue that can happen on a water pump is the impeller can come off the shaft. This will allow the water pump pulley to still turn with the belt, but no coolant will be circulated. This will cause the car to overheat rather quickly.

[J.S.]

Thanks. I installed the radiator a couple hours ago and still the temp dial goes to hot almost immediately. I checked the thermostat by taking it out and using the boiling water method. It opened and closed so its not that. Both hoses have coolant going through them but at one point both became like filled with air and was hard to compress. maybe that means something. Also when I shut the car off they compressed as if somethinf took the air out of them. I also called myself bleeding the thermostat screw and very little coolant came out but mostly steam and it never stopped. another problem is that the other bleeding screw abovce the water pump is not giving off steam or coolant. I opened and nothing happened. Maybe thats my problem. Other than that, I don't see what else could be wrong. The water pump must be working in order for the hoses to haev coolant coming through them. I checked the thermostat, the radiator isnt leaking. I only added one gallon of antifreeze so it may need another gallon. It doesn't stay hot. the dial sometimes falls all the way down below the fourth mark and goes bck up and sometimes it falls to the 3/4 mark and raises. Thats the latest and again thanks.

[GTP Dad]

If you have a radiator cap on this car leave it off and start the car. If there is air in the system the level in the radiator will drop. Refill and repeat until the level doesn't drop anymore. This is the simplest way to remove the air. I suspect that is why the guage is acting eratically.