Coolant overflow problems

[Faylix]

Just got finished replacing my intake manifold gaskets, and now, when I start the car up, it leaks coolant BADLY. It is leaking from the overflow hose... somehow my coolant is being pushed backwards in order to spit it out that hose.... any ideas what the problem could be?

[AaronGAGT]

Make sure your coolant cap is on tight. I had the same problem and tightening the cap fixed it.

[Blackrider]

You might have locked the cooling system how did you add colant?

[CruzinGT33]

yeah, I've crossthreaded the coolant cap before and it spit it up everywhere.

[Marksman]

Or it could be a bad thermostat. That is exactly what happened when mine stuck shut...

[atc3434]

I'll put money on the coolant cap, its easy to get on wrong...

[01silverGT]

check for air in the system.....start it up and open the bleeder on the bypass pipe, and also the the bleeder at the thermostat housing.....very likley there is air trapped in there....if no coolant comes out wait till it does then closse the bleeders. it's a 9/32" socket

[2002AmSE]

Has it been fixed yet?? It could be the cap not able to hold its rated 15psi, if it cant hold the pressure it tries to release it from the overflow hose, which will bring coolant out