speaking of radiator caps?

Ive addmittedly never owned a 4.0 jeep with the closed system until a few days ago on my new to me 87. My cap on the recovery tank always seems to be hissing when it pressurized or running. I dont imagine this is correct on this the way its supposed to be? Also I have yet to find an A/P store locally that has the cap in stock, what gives on these? better to buy a tank and cap for $50 which is in stock?

do you know the age of the one in there? If it is old i would.

Probably the original, are they prone to cracking apart? Wondered if there Is a write up covering switching to a later type "open system" somewhere in the archives?

dyna said:

Probably the original, are they prone to cracking apart? Wondered if there Is a write up covering switching to a later type "open system" somewhere in the archives?

Click to expand...

Quick and simple way I converted my closed system to open.



I purchased a open style 3 core radiator and swapped that in. After that, I removed the pressure tank and the lines to it. Swapped in new heater hoses and a heater control valve from a newer (I think I used a '95?) XJ. After that, I was able to fab up a mount for the coolant reservoir from a 94 XJ in place. See image. As of now, I am still looking to find a sensor that can work with the Renix system to activate the fan when coolant gets hot, as the newer radiator does not have the port for the sensor on it.




Hope that helps. PM me with questions.

Not sure if the threads are the same, but the laster thermostat housing has a port for a temp sensor.