You need to clean your glasses, BJ. <img src="/forums/images/graemlins/smile.gif" alt="" /> On his second post in this thread, he said it was puking the coolant.

Is the thermostat or water pump installed backwards?

water pump only goes 1 way i pulled the thermostat out and it still over heated takes about 10 min. to start puking

if i am not mistaken you have the closed system. i had the same problems on my 90 . i ended up pulling the thermastat & drilling 2 small holes in it. like 1/4 or smaller holes. that allowed the air to burb out fully. those dang closed systems are next to impossible to get all of the air out & that will give you grief. also, keep an eye on your pressure bottle make sure it doesn't start to look like a banana. they have have a really bad habit of warping & that will cause your system to fail. make sure that when you are burping the air out of the system that you have the heater on the whole time.

In modern heating systems the coolant flows thru the heater core at all times.. So having the heater "ON" doesn't matter a hoot when filling the coolant system.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

in the 1989 & 1990 xj's they used that closed sytsem & they also have that vacuum valve that controls the water flow to the heater core. i wonder if that valve is bad.

i tried to bypass the heater core and still puking

i am starting to go with Big Jim here & it sounds like a head gasket. my 90 xj was a total whore about the coolant system when i had to breach it once. but wow man you have replaced alot.

how about the lower radiator hose collapsing?? i remember my old 318 doing that alot. used to have to put in valve springs from 454's or 500's LOL just to keep it open.

maybe you had rust or debris or something in the system & after all of the work it worked into a spot & is stopping or seriously restricting the flow?

do you have a temp guage or dummy light in the jeep? maybe you need to see what your temp is when the puking starts?

it has a gauge and its puking at about 220. i had the head tested at a shop and they said pressure was good

How many times do I have to type it in here? There is only ONE WAY to find a small leak in a head gasket!! That is to fill up the coolant system and keep it full while watching the top level for bubbles while ideling!! It takes all of five minutes and is 100% correct!
If you are too full of yourself to go out and DO IT you will have this problem for a long time...won't you?
You have already found that simply THROWING PARTS at a problem is NEVER the answer.. One must first analize the problem and find what needs to be done before replacing ANYTHING!!
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />