All ok man, I take no offense. Did you read the title? Quick Radiator Test! Did I say get parts? I dont think rover cooling system has flaws. They are just much older need to be replaced. I own a bunch of discos stuck cooling no cooling issues just this latest I purchased now its fixed in a day. Just throwing in options, easy options which could have been fixed earlier on the post. Getting a camera and removing the same hose that I mentioned is even more time consuming than checking the actual flow.
Cheers

 

 

 

Major flaws

Cooling system is too small.
Thermostat design so particles can get trapped.
Horizontal pipe\hose design that allows the trapping of air.
Choice of using a really bad coolant.
Poor design for throttle plate cooler allowing leaks.
Not to mention the amount of hoses they used to achieve what they did was simply fckn stupid.

You're video isnt typical. The amount of rows that have to be clogged to make that little hose flow in your scenario is most of them. Cracking open that rad and looking at the blob of dexcool would have been an interesting and rewarding closure.


What was your solution?

 

I will check the shroud if its touching the fan that could make it slow down when slowing down. Touch the plastic inside if there are depressions or signs of rubbing.
Sorry, cant be technical like you. I got 4 discos and one 2003 since new which only water pump broke and replaced. No heating issues even during summer when A/C on and in traffic. My last disco recently had problem since the last owner used some sort of stop leak and clogged the radiator. Sediments and cake like silverish sprinkle sand like dust clogged it.
Design is not that bad, just like any vehicle, maintenance is required.

 

Hummer H3 Alpha was a vehicle with a “tiny” cooling system for the 5.3L V8. The units sold in Saudi Arabia had big dual electric efans to help with the fan clutch. In the states however they just left it with the fan clutch and no efan at all. I had serious issues keeping her cool in traffic, 180F thermostat helped a little, but it doesn’t make it run cooler once it passes the point it can’t circulate it quickly enough anymore. I was 215-225F easy!!! I found a Ford Explorer 9 blade metal fan vs GM’s cheap plastic one was a perfect fit (share the same fan clutch as a V8 ford Explorer). I then added a 14inch efan and used a PCM Efan wiring harness and had my PCM flashed to run the efan once the engine temp was past 195F or on whenever the AC was used. Radiator was microscopic, but the only choice was an aluminum unit for nearly 1k which I wasn’t going to try. I switched to green coolant added some water wetter and I went from 215-225F to 193-215F tops.

The D2 setup is pretty standard minus the thermostat used, but on a maintained D2 I don’t see the thermostat or radiator being an issue. TBH weak link is removed on all my D2’s, hard plastic line is replaced with 5/16 hose, 180F thermostat, and green coolant. I also ditch the one piece fan clutch/fan blade on 03-04’s and go to the 99-02 style setup with either the OEM blade or the dorman blade.

That is a MUCH better setup than any D2 ever rolled off the line with! Hood Louvers in TX would help, but I just haven’t found any I like for a decent price.

 

 

I don't think thats the right approach... you want to force all the airflow from the front through the radiator, and then ideally expel that heat from up high and rearwards. Cutting holes out of the hood is the logical solution, but I'm dubious as to how effective that is to reduce temps. I would want someone else to be the guinea pig before I cut holes in my hood

I think what ends up happening is the heat is expelled through the transmission tunnel and the bottom of the engine, which is perfectly adequate as the fan is pushing quite a bit of flow, not allowing hot air to linger around too long in the engine bay. Small cut outs in the hood is not going to magically make all that air flow through it