Autozone lent me a radiator pressure tester for our 2001 Cherokee XJ but it will not fit onto the radiator filler neck. Anyone else experience this problem? Vehicle losing a lot of coolant but has no visible external leaks. Thank you.

 

Check your engine oil ASAP.
Coolant leaking into the crank case is bad.
If it is leaking into the crank case DO NOT DRIVE IT until the leak is fixed.

 

Check your engine oil ASAP. It could be leaking into the crank case. Is it high on the dipstick? Mocha or milky looking?
Coolant leaking into the crank case is bad.
If it is DO NOT DRIVE IT until the leak is fixed.

 

I did experience the same thing but on my Mazda. None of the included adapters fit. In my case, the proper adapter was available, just not part of the loaner package. I am a bit surprised the XJ one was missing.

Anyway, I used the block tester (blue liquid) instead. (mine was good).