1996 2rz pouring coolant out of overflow cap. Please help

I’ve been dealing with this problem and I’m getting sick of it. It’s as simple as it sounds. The truck is running normal it just gushes out all of the liquid in the overflow tank after a couple minutes of idling of driving. Leaving it only with the water that the hose doesn’t reach if not bone dry. It doesn’t touch the coolant that’s in the radiator. The temp gauge doesn’t move past the halfway mark even at highway speeds.

These are the things I’ve done so far.
1. New radiator cap.
2. New thermostat.
3. Checked and cleaned the water pump. (It was all clean and damn near perfect)
4. Flush the radiator w some cleaning fluid I bought at Autozone. (Idk I was mad and just bought it bc I read cleans radiator).
5. New head gasket. I literally had no other idea of what to do.

All that and the problem still persists. Can anyone please help me?

 

Maybe plugged up radiator.

 

In theory that cant happen....if you blow into the reservoir feed tub....

it should just bubble out of the bottom return/feed tub at bottom of res...

and air only escape out the top reservoir overflow outlet....

there's nothin to push the fluid up to over flow....unless you use more water.


looks like you have the two hoses in the reservoir reversed....would be my guess


if there was a massive head leak that might overpower it...
but you say new head gasket.....

Are you sure you dont have another head leak......do you bubbles come out of your radiator with cap off when you first start up...

 

Cracked cylinder head...............?

 

You 1st need to confirm the cummbustion isn't getting into the cooling system. Although you did the typicall fix of the head gasket it still has issue over pressurizing the cooling system.
* did you check the head and block for flatness?
* head for cracks?
* proper hg torque and parts?
* thermostate in the proper direction?
* cooling system bleed properly?

 

I did everything relating to the head gasket by the book. Everything is torqued to spec and within tolerances. What hoses do you think I can switch around to test it?

 

I did everything I could I just didn’t machine the head bc honestly it’s never gotten to the point of overheating and it was out of my budget. I did bleed the system properly and make sure everything was within spec though.

 

The cap was fucking backwards…

 

Can relate. It’s the little things….
At least it wasn’t something worse.

 

Im not familiar with these heads but some can crack without much strain. Are you solid on no warpage even improper removal and torqueing can warp heads.

Next step for me would use a sniffer for blow by in the cooling system.

 

How does that even happen?

 

Told you so, this was an out layer, never hear of this...

so knew it had to be something stupid..........or it was something really really bad....



a lot here want to jump to extreme conclusions.....you should always try the simplest first.

 

I noticed, thanks for the help and advice man.

 

I guess it was when I was cleaning the overflow tank and went to put everything back together but just inverted the lines to the cap in my stupidity.

 

That aint that big of a deal...

......however when messing with all those hoses and tubes around the intake and TB...

your camera phone is your best friend......even the old pros trip up now and then...

usually from being in too big a hurry.