My car started making a popping sound around the radiator and I saw that the expansion coolant tank was bubbling over. I noticed it wasn’t tightened on all the way from a friend messing with it without my knowledge. I was hoping that it was just some air in the system but I took it to the shop and they said it needed a water pump and thermostat. Quoted me $2400 because the water pump is internal and driven by the timing chain so it needed a lot of labor hours to fix and I can’t afford it as it’s about what the car itself is worth.
The mechanic who looked at it before he did anything he called and told me that the engine was completely dry of coolant and asked if I authorized him to put coolant in it, so I agreed. And it actually ran for a couple of days without overheating after I left the shop. I know he couldn’t have added it to the expansion tank because nothing will flow out of it into the radiator and engine. So I am just wondering where he possibly put the coolant directly into the engine? It’s a closed coolant system with pressurized expansion tank, and there is no cap for the radiator to add there. I am just thinking that I could just add coolant however he did and take short trips until I can get another car or something figured out with this one. I attached a picture of the engine, so I am just wondering where I would be able to add coolant directly like the mechanic did to be able to just drive around short trips?
Thanks