Silverado coolant leak (still)

I've developed a not so small coolant leak on my 2000 silverado. It's not the water pump, I've checked that thoroughly. It looks likes it's coming from the front of the pass side head gasket. The really odd part of this
leak, and what makes it so hard to find is that it only happens at night after everything is cooled off. It doesn't leak when the motor is running, or when it's turned off, or when it's sat for a few days. It's only after it gets warm then shut down and cooled off (like not even warm to the touch) Then it burps a trickle of coolant out onto the floor. I've never acually seen it leak out but i've followed the moist path it takes. So what happens inside the coolant passage to create enough pressure to kind of burp out coolant and not leak when the motor is running? Any TSB's on head gaskets for the 5.3 L vortec? It's got less than 50K miles, and no as luck would have it no extended warranty. Thanks. BC
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Spring for a pair of valve cover gaskets, and re-torque the heads. Pull the plug and read it, a super clean plug is getting steam cleaned.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Is there a frost plug in the heater core? My 03 astro with 50 thou K has had this problem.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
"chase12" wrote

While it's not a real common problem yet, I've seen a number of these head gaskets leaks in our shop. Seems to mainly be the passenger side. Here is a picture of what happens...the gasket just splits right at a coolant passage.
http://members.shaw.ca/ianrmac/Images/DSC00755-1.JPG

Many coolant leaks occur when the engine is cold.....water pumps, gaskets...etc. It usually has to do with parts expanding/contracting as they heat up and cool down.

Not that I'm aware of. I'm sure that if it becomes an epidemic like the 2.2 head gaskets, there will be some sort of hidden warranty. If you get it fixed.....always keep track of the receipts for the work, in the event that it becomes a warrantable item. You can get re-imbursed down the road.
Ian
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I guess that's what I was looking for. Thanks for the info. It's going to the shop this week. I'll ask to see the gasket and see if it did what your pic showed. Thanks again.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Exhaust gas pressure blows the water away from the combustion chamber, keeping most of it out, steam, however, can pass through the smallest of openings.
My old Malibu had a cracked head. Never " leaked " a drop cold, but would burp out 2 quarts every time it was driven.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.