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Radiator Blow Out

sarav

sarav

Full Member
Joined
May 21, 2004
Messages
142
Location
Richmond, VA
Haven't been on in a while, but am hoping someone can help. I replaced the original water pump on my 02 Z71 this weekend. 221k. No issues there. Problem came when I was trying to burp any air out. Got some, but I'm pretty sure not all. Truck ran fine with no overheating. However, today, I had to hit the throttle hard in traffic and a plume of water shot out of the front end right over top of the drivers turn signal. Low Coolant light came on and temp went up. Luckily I made it home before too hot. There's coolant all over the front driver's side and the edge of the hood, but none really anywhere else. All the hoses are in tact and connected.

What I noticed is the drain hose for the radiator is stored vertically in a loop on the side of the radiator. Question: could the air and additional pressure from full throttle have blown out the petcock seal and shot water up and out of the drain hose? It would have hit the edge of the radiator support and hood and gone right out the front like your thumb over the end of a garden hose. This is exactly what it looked like from my seat.

I'm crawling under it tomorrow and seeing if it is leaking, but can't find anything to explain this online. I figure if the petcock seal is blown, the radiator will leak when I drop the hose. I'm just hoping I don't have a bigger leak in the radiator itself.

Hoping someone can help....
 
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Hopefully it's just the thermostat not opening or maybe one of the hoses was not clamped. Also when you burb the system make sure to have the heater on low. Keep us posted.
 
PRessure is limited by the cap on the overflow tank... 15 psi I think is rating
System pressure is pretty constant once up to operating temp and is kept high to increase coolant boiling temp.

All revving up really does is increase water flow in system

Find leak by getting pressure test...
 
Advance Auto and Autozone each offer the pressure testing kit as a free rental/loaner, at least in my area.

Here is a video of someone performing the test, in case that helps.
 
Thanks guys. I'm checking it out this afternoon. I was just wondering if anyone had heard of or experienced a blow out from that drain tube. I'll let you know what I find.
 
I just replaced my entire cooling system because I had a radiator leak somewhere in the vicinity of the drain.
 
frito said:
I just replaced my entire cooling system because I had a radiator leak somewhere in the vicinity of the drain.
Click to expand...
Me. too.
 
Ok, culprit found. The radiator is leaking where the core meets the tank just below the top in front driver's side. It's right near where the top of the drain hose is stored. Thanks for the responses. Another question, do I have to remove the radiator support to swap the radiator, or if I remove the shrouds and fan, can I slip the radiator out past it?
 
On my '03 I just had to remove the shroud. Since I was doing everything I removed the fan. I don't know if that is required for just the radiator.

 
I did as Frito did.
 
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