Coolant reservoir overflow

pretty hot day today, after driving around town for a little, Jeep was getting hot, after I turned it off, the reservoir was pissing coolant like crazy, first time it’s done that coolant is at proper level
I have a whole new cooling system and replaced fan clutch and radiator but I am missing the electric fan. my question is why would it come out so heavy from the reservoir? I’m scheduled for a 5 hour trip next week so I need to make sure this doesn’t happen again.
Thank you!

 

Thermostat replaced? Whats the coolant level of the reservoir when engine is cold? What electric fan is missing? Proper coolant mixture?

 

Yes sir thermostat, level when cold is at proper level just up to the full line. Coolant mixture is good. Minus the rust that was in the system when I bought it but I had it flushed multiple times. And the electric fan I’m talking about is the one on the driver side of the radiator, right now I only have the mechanical fan working to cool it down.

 

Couple things to check before....:
1) radiator cap not holding pressure allowing hot expanded coolant to escape
2) thermostat installed incorrectly or sticking
3) clog in the system resulting in over heat
4) replace the electric fan

 

Thanks man I’ll check em all out

 

Sometimes when coolant is replaced an air pocket can develop in the cooling system, which can cause an overheat. Driving the vehicle up and down steep hills can push it out. After following steps 1-4 above.

 

Awesome thank you!
just got a new thermostat today and electric fan