The other day, after replacing the power steering pump, taking it for a drive, and popping the hood when getting back to make sure PSF was fine, I noticed a lot of liquid coming out of the overflow tube connected to the radiator reservoir. Today I ran a quick errand (5-10 minutes driving total), put the disco II (2004) in the garage, and again popped the hood. This time I saw steam coming from the hood and what looked like a waterfall coming from under the engine compartment. I opened the hood and saw that the overflow tube was pouring our coolant from the reservoir all over the garage floor -_-. There was still some coolant in the reservoir, but it is for sure low. I ran it again around the block, keeping an eye on the temp gauge the entire time, and had no issues. I got back and left the engine running and looked under the hood. The reservoir was bubbling and looked completely full, a little bit of liquid coming out of the overflow, but very minor, then all of a sudden it stopped and the reservoir looked nearly empty again. So here is my question: What is going on? Air in the system? Bad radiator? Bad hoses?

 

Post this in the D2 section for better traction. Here are some pointers in the meantime.

If the temp gauge starts climbing in your scenario, it's already too late. Get an OBD reader for accurate temps.

Are there other external leaks that would point to a failed hose or failed radiator?
Did the PSP repair inadvertently disturb any of the cooling system components?
- A cold pressure test could isolate any of those possibilities.

Sounds potentially like a failed thermostat.
- Remove and put in a pot of boiling water to test.

A failed headgasket could cause these symptoms however it's way too early to tell.
- A combustion gas test kit would be a good idea to perhaps rule that out.

 

I should have posted there from the jump, will move it. I have a combustion kit. I will try that ASAP. I've feared the gaskets since I got it, guess there is no time like the present to test for that.

 

I'm trying to run the combustion test this morning, but I cannot get it to bubble through the fluid to save my life. I've connected it to a vac line per the instructions and still nothing, perhaps not the right vac line? Could it be the thermostat is stuck? I opened the bleeder and that seemed to do the trick, but fluid was going everywhere. Not ideal I know.

 

so it was fine before you replaced the PS pump? did you unhook any coolant lines? did you get air in system and not fill/bleed it correctly?

 

It seemed to be fine. I think I have two threads on the Disco II forum at the moment, this one got brought in from mods when I asked in the general help section. It did start after the power steering pump was replaced. Just did a pressure test and have leaks at a few hoses that are 17 years old. I am going to replace the who system (minus the water pump as it is only 30k miles old).