I picked up this car in non-running condition many years ago. I got it running but it just sits and sits and develops more problems from sitting and being neglected. Had a baby, got divorced, parents died seven months apart, got married, had another baby and now here I am able to spend some time working on stuff again after a long hiatus.

The car popped two freeze plugs at one point from sitting outside with straight water. There is plenty of rust in the cooling system from sitting for years with straight water.

I have the freeze plugs back in. I started the car and worked on bleeding the air out of the system. My hope was to run some radiator flush for a while and work on cleaning out the insides. There used both bleed screws on the engine. I got air out, then water, then sputtering water and steam. The temp gauge was rising toward the red zone, so I shut the engine off. I heard lots of bubbling and gurgling inside the engine.

I have a few theories about what's going on, but I'm a hack and could use some guidance. I am thinking that:

1. The rust is keeping the t-stat closed
2. The rust has caused the water pump to fail
3. The rust is blocking the passages in the radiator

I feel like #3 is less likely. What do you think? Am I on the right track? Should I just remove the t-stat and water pump and check them out?

 

Check to make sure the radiator overflow and vent lines aren't reversed. If so, the system won't pressurize and will boil.

 

I would not thought this was possible to do. I'm pretty sure that, after I had the car apart for an Opti swap years ago, I put it back together and ran it for a while on the street before it began to sit. In other words, those lines must have been on correctly because the car did not begin to have these cooling system problems until more recently, after the freeze plug (core plug, I know) popped and the system was dry and rusty. I will remove the battery and try to confirm the line orientation, though.

The coolant began to spill out from the overflow tank cap today after running the car for a while. The tank had been filled with the right amount prior to starting the car.

 

The system is pressurized, so it can't run properly without the cap on Any system will overflow at the cap as it heats up and if the cap is off.

The place where the tubes get reversed is at the filler neck, right under the radiator cap. The highest tube, which engages the radiator pressure cap, should go to the overflow tank.