2005 silverado 5.3 puking all the coolant out of the overflow hose

[Javier96]

Any one have a clue why my 2005 silverado pukes all the coolant out the overflow hose from the coolant tank once the engine warms up ?

[riverbanks]

Was any part changed recently on cooling system?

[Javier96]

I recently bought the truck it was fine for a week then it started throwing the coolant out, i don't think the previous owner changed anything

[riverbanks]

During the week,did you notice any hot problems?guage spiking?hot smell from engine?a likely cause is bad head gasket,likely,but not a 100%,you could do a exhaust gas in coolant litmus test,and what does coolant jug fluid look like,clean,dirty,particles?just thinking,stop leak or something along those lines

[Javier96]

It ran fine during that week no problems the coolant come back out clean

 

[davester]

maybe feel the upper radiator hose when the engine gets hot, to see if coolant is flowing through the radiator (or use an IR gun).

 

It might just be a bad thermostat, but it wouldn't surprise me if the P.O. just put in something to seal up the coolant system quick after finding out the vehicle was due for an expensive repair, then sold it to you.

[CamGTP]

A bad coolant cap could be something to look into as well. If the cap is bad it can't hold the coolant pressure and it will let it boil over.

[swathdiver]

7 hours ago, Javier96 said:

Any one have a clue why my 2005 silverado pukes all the coolant out the overflow hose from the coolant tank once the engine warms up ?

Assuming you do not have a blown head gasket, if the previous owner changed the radiator and bought an aftermarket one, they usually do not have a restriction in the fitting/hose to the return tank which can cause the problem you are describing and or failure to get to temperature and run too cool.  If the radiator is OE, do a compression test.