Last year my 2002 - Ram 1500 3.6L overheated and dropped all the coolant onto the highway. I had it towed to garage where they replaced the thermostat. The system continued to get hot (temp guage at half) but never overheated for 8 months after that. It has started to overheat again. I noticed that the coolant was spraying out of crack in the top of the coolant reservoir. I just replaced it this afternoon, but still have overheating. It only takes about 20-30 minutes to start overheating.

I noticed that the radiator overflow into the reservoir is constant.

I burped the system to try and get all the air out, but the heater does not work.
Just cool air coming out of vents.

Does this mean that my radiator is not being engaged? Is the coolant bypassing this critical step? Coolant in reservoir is hot, hot, hot.

Thank you for taking the time to respond. What is the next step in diagnosing this problem?

 

Welcome to DF. I will move your post to the correct section.

For future reference:
https://dodgeforum.com/forum/dodge-r...ead-first.html

 

Hello,
It sounds to me like your heater core is plugged. You can remove the 2 lines going to it and try to flush it out with a garden hose from both directions.
Your radiator has probably suffered the same fate. Try feeling over it after the engine warms up to see if the radiator is warming up. It may be totally blocked and cold but you'll be able to feel around to get an idea.
Steve

 

I have to agree that it sounds like your heater core is plugged up, which is not allowing the coolant to flow.

Make sure the shop used HOAT Coolant.... (usually Orange) if they used the Green stuff you're asking for problems.

You may need to reverse flush your heater core as well as the rest of the system.

Let us know how you make out.