How to fill radiator

[Jacobsmithxxox]

Hey, I’ve got a 1991 1.9 diesel Citroen BX. My second month owning her. It’s got a little radiator leak at the moment. Does anyone know what coolant I need to be filling it back up with to check the level is always good? Also how I see where to fill the radiator too as it’s dark black plastic coolant reservoir on the side of the radiator,,,

Massive thanks in advance if you can help

[Jugostran]

Hey there.
Assuming the setup is similar to my petrol BX (which it should be, judging by the photographs), the procedure should also be similar. Fill the coolant with whatever colour is in it at the moment. Mine uses the basic green stuff (though I think they may have used the pink or blue stuff from factory, not exactly sure what spec as Total Antigel isn't a thing anymore). If you're unsure, just use distilled water (though seen as its getting colder, you may want to be careful as to not dilute the coolant too much). To fill the coolant, wait for the engine to cool off, open the radiator fill cap and fill it until its about 5cm from the top of the fill neck. To check levels - shine a light down into the fill neck.
You may also want to clear the system of air. Turn the engine from cold (with the radiator cap removed) - and have the heater on (to get the coolant going through the heater core). Then just fill as necessary if the coolant level goes down. Close the cap by locating its two tabs into the notches on the filler neck - then push down and twist until fully seated.

[Jacobsmithxxox]

Thank you very much! That was perfect answered all my questions! Mine is green too so will get in this now! Thank you again

[Jugostran]

Cheers. Seen as a few days have gone by, did you end up filling the coolant? I assume everything went correctly.

[Jacobsmithxxox]

Yea filled with some green! I could see the coolant in it was green as I have a little drip from the radiator. So I just wanted to be able to keep it topped up until I am able get it fixed at a garage. I’ve only had it around two moths so I’m still getting to learn stuff about her aha

[Jugostran]

Good to hear. That drip shouldn't be too difficult to rectify. As long as the heater core isn't leaking and the rest of the system is operating fine, a new radiator should do the trick.

[Jacobsmithxxox]

Yea I’ve seen on a previous MOT slip it said weak radiator core so I think it should just be a new rad! They seem readily available online from a Quick Look too! So shouldn’t be as bad as the fuel pipes I just had to replace

[Jugostran]

Oh then it's easy pickings. New rad and off you go. Anyway, be glad that you have a diesel when it comes to bad fuel hoses. In a petrol you're left with petrol odor throughout the car while trying to figure out which of the 30+ year old hoses decided to start leaking. Meanwhile the new rubber you buy is so bad it dry rots after a few years. I find the best solution is to use E85-rated hoses from reputable brands.