Jeep runs hot water pump and rad new. Heater only

check the coolant pump is good and the radiator is not blocked both air flow thru the core and coolant flow thru water tubes, you can check for coolant flow thru the rad by feeling the core for any cold spots after running engine til warm then switch. off the radiator should be hot at top and cooler has you feel down with even temp all along any cold spot means the rad is partialy blocked.if the rad is red hot at top and cold at bottom it may be the pump if its got a electric cooling fan check thats working ok, good luck

Water pump?Air lock!!!

3.8L V6, (from old 3.3l ) OHV ,push rod simple )
same car as one of mine, same engine, mine is 08
p0300 means all 6 cylinders fail or combustion pressure, weak.
at random.
so not 6 bad spark plugs news and gaped to speck
so is bad fuel?
so is 6 clogged injectors,, NO.
hot engine has normal idle rpm 800 or screams only.
yes that is called gross misfire and lost of engine power too you forgot to say.
got AF radiator water in the oil pan , looks like like chocolate milk?
mine has 100k runs like new, water pump only failure ever, 100k miles me.
seems like bad fuel to me. ,diesel put in to gasoline tank?
the only weakness this motor I know is 2.
1:lower manifold gasket leaks and AF coolant falls to top of engine and down.
replace coolant every 5years is win to avoid that.
2: egr failure sticking open and a pain to reach, unless right finder pulled fully
im sure compression tests pass at 150psi up. sure. 50k miles how can it fail.?

make sure at AM dead cold engine, rad cap off rad neck is 100% full of AF.
never let it drop, and keep side tank 1/2 full cold.

never forget to burp the coolant here as you replace it all

as you fill it up.(AF antifreeze coolant)
hose off here, heater)
fill rad until it leaks here
hose back
then fill rad full to top of neck.




https://drive.proton.me/urls/2AJBWHFE3R#n9DXuC8sIcOD

link is new pump installed steps PDF

My 2006 f-150 4.2L 113,000 miles heater blows cool when at Idle ,But when driving the heater blows hot. Change thermostat change water pump change the Rad. change the blend door motor
flush the block bleed the system add new green coolant. After all that still blowing cool air at Idle. What is causing this problem.

Fill the rad or overflow bottle right to the top and run the engine with no cap on,if you see a constant flow of bubbles your head gasket is leaking or you have a crack somewhere in the cooling system.

only one! have you had a "sniffer test done!" this test takes some water out the rad and checkes it for hydrocarbons if there there its a head gasket leaking or head cracked letting hot gases into the water jaket

first of all the water pump doesn't have a heater, all the water pump does is cycle water (coolant) throughout the cooling system, the heater is up inside the dash behind the glove box.

I would feel the two 3/4" heater hoses that run from the engine into the heater core, if both of them are hot (providing the engine is at full temp) it one is hot and the other is cold maybe the heater core is plugged.

Remove and raise upper hose at thermostat end and remove lower rad hose.
Fill rad with a hose and watch for flow from bottom rad hose and/ or bottom rad hose connecton.......water should fall though rad easily.
Honda rads are cheap.....any restriction....replace rad.

Remove thermostat....fill thermostat housing with hose and watch for water flow at bottom rad hose.
Flush good.

Remove heater hoses.......flush back and forth until a good flow is present "With heater control set to hot" if no or poor flow....replace heater core.

Stop leak can plug everything.

Also.......not likely causing over heating....but ....at your mileage,if you do not know if the timing belt has been changed.....CHANGE IT NOW!
Water pump is optional at this mileage.

You probably have an air lock. Remove a heater hose and get all the air out. Then run it with the rad cap off until it warms up. You should see the water level drop when it finally goes, or if you got the air out with the heater hose, it should be okay.

You can tell if your water pump is running backwards by the way the radiator fan is running. If the ran is pulling air from the radiator then the water pump is running the right way, if it's pushing air toward the radiator then your water pump is running the wrong way too. There should be a sticker on the fan shroud or on the hood to the direction the serpentine belt should run. IF the water pump is running the right direction, then it needs to be replaced. Good luck and hope this helps.