Isn't the "coolant bypass loop" constantly flowing coolant to/thru the bottle the moment the motor starts, regardless of the t-stat being open/closed?

 

I believe so but with you saying it took 45 minutes before it began to boil over. Thus the small bypass hose could not move the water fast enough and it begins to boil over

 

Ill post pics of y system in a bit

 

Then replace the cap as I suggested. 703-1396 at Napa.

 

Ok I have tht cap and it dosent get tight it tightens and then strips and becomes loose! The old cap didn't do that. The napa cap blew right off the tank this afternoon while wheeling I turned off the jeep because it was reving to 3k after I stalled it and te cap blew off. Is there a special procedure to replace the coolant on bleeding the system ? I want to replace my hoses and thermostat and fill with green coolant

 

Your coolant bottle must be too far gone in teh threads department. Get a new one and use the Napa cap on it.

 

The old cap fits got a new on from car quest it has a rubber. Seal in it I got a new thermo and seal and green coolant

 

Ok bought a new cap 2 gallons green coolant a new thermostat 195degree I had a 160 in there. Drained and flushed the radiator and system till the water flowed clear. Plugged it all back up changed thermo. Filled upper radiator hose untill coolant came out the thermo housing reattached hoses. And checked tightness of all clamps hoses are in ok shape. Topped up coolant resivior. Ran with heater on high untill it was warmed up and shut off jeep and let cool with system open. Once cool check level and tightens cap and performed road test to nearest mud hole 17 miles away parked in the yard. I think it's fixed now. I will know when I go out in the am to drive her to work if she's pissed her self ! The coolant in the radiatior was a rusty brown color now it's a nice radio active green

 

What new cap did you buy?

 

The replacement from Carquest

 

This is what happens with the extended life antifreeze (oat,Dexcool) use conventional green and change every 2 years. I don't give a dam about antifreeze lasting (there talking freeze protection) if it turns into mud.
Conventional silicate coolant will not turn brown, it just loses its freeze protection and has to be changed more often. It will not eat aluminum but the extended life crap will once it turns brown. It will also eat gaskets,water pump impellors and plastic....nasty,evil stuff!!!!

 

Well seems to be fixed but now my alt isn't charging ! **** my life!

 

welcome to jeep land!

I know on my old Ranger I had the same issue--coolant boiling/blowing the cap off of the reservoir. Ended up being cracked heads and a bad head gasket.

 

i hope its not a had head! i seem to have it fixed now time to repalce the alt! it was kinda weak before the mud puddle last nigth still worked on the other side of it but this morning i drove to work noticed it was rigth abouve 12 v and at times below and a few times went as high as 13v i assume seeing as how th enumbers are not marked other than 9 14 and 18 on the guage

 

Check your grounds. I thought my alt was going out one time and it turned out that my grounds weren't as fresh as they should be.