So my 88 SE overheated while idling very high (2k) during idle adjustments. I turned it off and the stock radiator blew up (plastic top section completely blew open)
Installed a new aluminum radiator and now the overflow does not fill up. Every time I check the radiator's levels it is completely full but it refuses to flow to the overflow. I saw some threads here saying the hose on the overflow is supposed to lead to nothing but when I bought this car, the hose was connected to the cap on the radiator and that seemed to work for a bit until the overheat. so I did the same for this new radiator as I didn't want to install it differently.


Why is the overflow empty? Could it just be that I didn't bleed it properly when pouring in new coolant? Should I try running with the hose from the reservoir off? Supposedly FCs came with a short hose on it that connects to nothing and functions as a vent. But mine came with a longer hose that connects to the nipple on the radiator cap.

Lurked for hours and couldn't find an answer. Will try any suggestions. Thanks.

 

The hose on your rad should connect to the bottom of an overflow tank, where the coolant is pushed when hot and recovered when cooled.
Given that your last radiator "exploded"- which is not normal- the first thing I'd check is the pressure cap, which may not be functioning.

 

Also, have you had the system pressure checked?

 

overflow is usually a function of the radiator cap. Also make sure you burp all the air out of the system as per workshop manual.