My son (16) bought a 95 Z28. Road tested fine and ran good when he bought it. Blew a radiator last week. When we replaced it we found that the water pump was out. So today we replaced the water pump and got it all back together. In an attempt to flush the radiator it seems there is still something not right. Hoses and thermostat replaced.

Had the cap on and was able to get pressure on the hoses but the temp went high. Shut it off to cool a bit to get the cap off to see if we had good flow. Seems not to be good flow but there is hot water coming from the top of engine into the radiator at the fill cap (this is where i say I have some older automotive experience but i do not know where this flow comes from).

As it is now, first thought I have is there something else that can fail that would cause the water pump to fail that may now have destroyed this new refurb pump. (just my first thought).

I know there are many that understand this car and system and I had to dialog back and forth on these forums. so if anyone is willing to talk to me directly i am willing to make the phone or other connection.

I would like to get this thing running again for my son since he is do upset over this. He's feeling he just wasted his $$$

Any help is appreciated.

Thanks,
Scott

 

Was the engine overheating when the old radiator blew?
Have you bled the cooling system when you refilled it?
Except for leaks water pumps usually do not go bad, what was wrong with yours?
Are the fans coming on?

 

sounds like air in the system or faulty stat.

 

^^^ agree. if the motor overheated you may have blown a headgasket and or warped a head. heres some help for bleading the air out. found in the how to and faq sticky at the top of the 4th gen section. https://camaroforums.com/forum/lt1-l...-system-66742/

 

I am not sure on the actual events. I was away when it happened last week. The symptom was that the radiator was leaking, seems it blew open.

Purchased and installed a new radiator, upper and lower hose and thermostat.

Filled radiator with water. Left cap off and started the car to get water flow. Had planned to put the cap on to build pressure but the temp gage showed it getting hot but no water flow.

At this time we figured it was the water pump. Removed the pump and could easily spin the pump with two fingers. Compared to the new pump which was very hard to turn. So I am sure the pump was bad, Napa guy confirmed it too.

While the pump was off I wanted to flush the coolant from the block. There are 4 holes, 2 on the left and 2 on the right as you face the motor. On each side there is a round hole and an irregular shaped hole. Using a hose and holding it to the round hole, I got water to flush from the irregular shaped hole below it. I was expecting water to come from the other side as well. (I don't know how the water flows through the engine block so I don't know if that is correct or not.)

I have not tried to bleed the system, I did notice bleed screws and wondered what they were used for. I will try that today.

 

I forgot to add, thank you all so far for your help.

 

Thanks again for your help. The bleeding of the coolant system did the trick. So far the only "damage" that possibly resulted was a knock in one of the cylinders when the car is initially started. I am not sure if it was there or not before the overheating since the outside temperature was not as cold as it has been lately. Seems when the oil warms a bit then the knock goes away.

 

Be sure to use those bleeder screws a few times a more throughout the week just to make sure all air pockets are out, and keeping that heater on for full circulation as well.

 

sounds like a exhaust manifold leak to me. or lose spark plug. check and see if you can track it.