So 2 weeks ago my dad noticed that there was a puddle of something up under my truck. That night while my truck sat in the garage, it leaked out a nice 6 sq ft puddle of water. When I have the engine running it doesnt leak that bad but it still drips down. So yesterday I was cutting grass, and when I got done there was a puddle of water under my truck. I bought some radiator stop leak which I will put in today. My overflow reservoir is filled up almost to the top. The hose running from there to the radiator was clogged but I blew it out. The level in the tank still has not gone down. When it does leak while the motor is running, its coming from behind the water pump.

Any help would be appreciated. Today I will be going to Advance Auto to get a new radiator cap.

 

if it is leaking from behind the water pump, i don't know how much help the radiator stop leak will give you. You might just have to take the water pump off and put new gaskets or RTV to seal it up. Sounds like the gasket just busted.

 

Radiator stop leak only plugs up heater cores and radiator cores, I would never use it.

 

The next problem is why the overflow reservoir is full and not emptying. I unclogged the hose yesterday.

 

Is it full b/c fluid came in from the radiator or b/c it was filled up all the way while the radiator was filled up all the way?

Also, what color of water is on the ground?

 

If it's leaking from behind the water pump, most likely the seals are bad in the pump. Replace it and call it a day.

 

My radiator will have low water and the tank will be full. The color of the water is green. If the seals are bad, does that mean I have to replace the whole water pump or just the gaskets and stuff?

 

Usually the whole pump, they're not too expensive, and when you get in there, why risk putting an old pump back on after doing all that work?

 

I had a similar problem. However, mine turned out to be the heater core. It never leaked inside but some how leaked outside.