How do you bleed the air from a 1988 Jeep Cherokee cooling system?

Answer 1

Answer

The 1988 jeep Cherokee Laredo has the sealed cooling system. Many bloggers have posted instructions on how to bleed or burp by removing the rad cap. This does not exist on the 88. Here is what I have come across during my search ( I am currently attempting to bleed my system), that you need to remove the temperature sensor valve. There is a bolt near the back of the valve cover under the hood on the driver's side. There is a small temperature fitting on top of the bolt that is easily pulled off. This is the sensor that feeds your dashboard gauge. When pulled off the temp will read zero. This procedure must be done after the car has cooled off, otherwise you will end up badly burned and needing to replace the bolt you just launched after being sprayed by boiling hot coolant. To start, be sure that the sensor bolt is higher than the front of the valve cover. In other words you need to lift the back of the car or park on a steep enough incline so that the back of the valve cover is higher than the front. When the bolt is removed you will hear air bubbles escape and hiss out as it leaves the hole. Immediately replace the bolt when coolant begins to flow. This process will need to be completed 5 or 6 times and will take most of the day because after each attempt you need to run the car to temperature and let cool before trying again. This will fix problems related to the Jeep running cooler than usual or over heating in heavy traffic. It will also fix the problem with your heater not blowing hot air. The bolt requires a 13m deep socket to be removed. It may also fix problems with leaking coolant.

What I did the other day was to Remove the upper radiator hose and finish filling the radiator that way. It can take forever trying to add through the coolant bottle and then it still will not take as much coolant as needed. Very frustrating, be nice to have a real radiator cap.