Extreme coolant loss but no system pressure

[ThreeQuarterTon]

Working on a guys truck which he swears it’s head gaskets, he already bought studs, gaskets etc. long story short, once he brought the truck over for me to work on, I First noticed his coolant system builds zero pressure. Pressure checked and holds pressure fine and no leaks other than VERY small snail trail out of weep hole which was dried up. Spent a good amount of time burping the system correctly. Run it to operating temp and drive for awhile and overflow side of surge tank is completely full and running out down wheel well but still zero pressure in system. Guy replaced his cap three times and also a new tank, also changed thermostats. Truck is tuned and egr shut off, not blocked. Heat in cab works great. Aren’t These cooling systems designed to run with pressure, why is his not getting any? Still headgaskets or egr? My first time working on lml, I have a built lly I know like the back of my hand

 

[dmaxfireman]

Are you talking about the weep hole on the water pump?

 

[clrussell]

If it’s running antifreeze down the wheel well it needs head gaskets.

Go run the piss out of it and see if it puked coolant, if it did replace the gaskets, have the heads checked and go on with life.