scroll down on the wj page, and read the thread https://www.jeepforum.com/forum/f310/air-locked-heater-core-matrix-4420081/ and then go to work. your post is a bit confusing. you fixed it so the temps aren't getting hot, but then you say the temps are going up? flush the heater core, in both directions? good radiator cap? recirc door working? water pump is working? temp gauge is right? shoot the hoses with an ir gun, and verify temps? thermostat?

 

I got it to a point where it still starts to overheat i simply slowed the process down

 

If your thermostat is stuck closed it won't cycle into the engine and will overheat. Ive bled my cooling system about 4 times now. Swapped out my engine and my cheap side decided to reuse a thermostat and yeah thats what happened.

 

what kind of fan? electric, hydraulic, mechanical?
radiator? new, used? plastic tanks, aluminum, copper?
water pump? new or used? inspect the impeller blades?
fan shroud? fan inside it? sealed tight to the radiator sides, top and bottom?
thermostat? degrees? new, used? tested in a pot of water on the stove, with a thermometer?
heater core? new or used? flushed in both directions until water flowed clear?

engine block flushed? remove thermostat and attach garden hose to bottom hose, flush water out of top hose? flushed top to bottom?
a/c condenser in front of radiator? fins mashed flat? packed full of dirt/dead bugs, etc?
trans cooler in front of radiator? fins, dirt, etc, listed above?


i haven't done a 4.7 but everyone says the radiator cap isn't the highest point in the cooling system. have you done the bleed screw deal yet? ran it up onto ramps, or used jackstands to raise the front as high as you can?


you have 2 different problems you are talking about. fix just one, then work the other. overheating should be more of a concern than no heat inside, even though they might be remotely connected, solve 1 problem at a time. the things i listed to try, are free and relatively easy to do. fix the cooling system, then work the heater.:nerd:

 

It's a hydro fan, heater core is probably oem. It was flushed prior to putting engine in. The engine is a fresh rebuild. It is currently on jack stand to keep the bleeder screw the highest. Radiator is plastic ends. It was flushed prior to being re installed

 

The system is designed to be self-bleeding, so the factory air bleed procedure has always worked for me: Fill the rad, then fill through the bleed screw hole until it overflows, then top off the reservoir and just drive it, checking and refilling the reservoir as required after each cool-down.

After about three to four drive cycles the system is fully bled. No need to have the front end raised or any of that.

 

Martinbuilt has a great way to bleed it on his youtube channel with a funnel and a short piece of clear hose. This is how i do all of mine now. It has taken me as much as 45 mins idling to get all the air out of some of these engines.

 

even though it's self-bleeding, you can still get air pockets in the block and head, which is why i mention parking/lifting at extreme angles, to help the process. if you could remove the thermostat from the equation, you could blast the coolant in under pressure and bleed it instantly. the thermostat is what causes the problems, not allowing water to flow fast enough to burp out the air in one shot.

 

If it's supposed to be self-bleeding, how come there's such an elaborate (& time consuming) procedure for bleeding it?

 

its a good question, without any really decent answer. i imagine it does self-bleed, eventually......


you try to use all the tricks you can, to help speed it up. you can help it by pre-filling the heating system from the waterpump, through the heater core, back to the waterpump. pull water through with a vacuum, or push it through with pressure, reattach the lines without allowing coolant to leak,or air to get in. i'd run it until warm, and then get some glove on, and start squeezing the upper and lower hoses to try to "milk" out any air. extreme angles to try to work the air to the top might help. make sure you don't have any leaks in the system. pressurize or pull vacuum on the radiator fill, and see if it leaks down, and if so, how long it takes. try a cap from another vehicle (if you have one) and see if it makes a difference.

 

Been super busy with work so i haven't had time to mess with it. Going to send it to a friend shop next fri. They are going to push coolant through the system to make sure there is no air stuck in the system

 

Lisle 24680 Spill-Free Funnel is the only way I use to bleed cooling systems, it simply works. Crank the heat to full open and let idle till the thermostat opens at least once. You can pump the hoses during that time carefully and help speed up the process but still wait till the stat opens.

 

I've been squeezing top hoses when refilling rads without really knowing why since before bleeding a cooling system was ever introduced as a specific task/procedure. iirc, that came in when certain European manufacturers started fitting bleed valves so, suddenly, you had to do, by the book, something that previously you'd done as a matter of course.

A classic example of making a simple talk needlessly more complicated by a solution to a problem that didn't exist.