You should be able get good prices and reasonable shipping from UK sources...

Surely the UK outfits like Rimmer Bros ship to CA...

 

So did you actually flush the heater core?
As mollusc pointed out, coolant flows through it all the time, and having good heat doesn't mean it's clear.
If it's gummed up, coolant slows down, and could cause the temperature to rise.
It needs flushed out with water from a garden hose, enough pressure to push any built up crud out.
It's also not directional, so you can flush it through both pipes coming through the firewall.

 

You said 108*C (226*F) in city,
now what is your temp if you drive study at lets say 50mph for 10-15 min, & also mention at what ambient temp,

 

I have honestly never personally had a single issue with the Motorad 180F thermostat for the D2. In fact it’s the main one I used on customers/friends D2’s this year as the good Britpart 180F thermostats stamped at 78C are apparently a thing of the past. If any black thermostat has a dull color & the mount for a Freelander = RUN AS FAST AS YOU CAN!!!

The 180F Motorad thermostat is available at any Auto Zone for 33.00 and it works excellent. 90% of all thermostats made are actually motorad & then shipped off to their final vendor & slapped into say an AC Delco, Gates, or Murray box.

 

A few reports in the last 12 months that new 180 thermostats from suppliers such as lucky 8 have been bad out of the box.
I had a bad one from lucky 8 and they do ship to Canada as I’m in Ontario
I however bought 3 soft spring warm weather thermostats from Atlantic British and never had a problem
boiling the thermostat in a pot of water in my case my opinion doesn’t give you full picture and is not a accurate test
I boiled the lucky 8 180 stat and yes it opened at 180-190 etc. But your boiling the body of the stat as well. It’s not a good test
in my case I put in the Atlantic British tstat and bang it worked

 

@Tristan Stumpf If you old rad was clogged with some kind of stop leak the odds are your block is too, an over the counter flush can not l always get rid of it. It is hard to diagnose, but I am in the Fraser Valley just a long ferry ride away. I ran 212 to 220 with a stock thermostat, with 180 I have from Atlantic British I run 188 to 194 - moving.

So a couple of things,

• use fahrenheit it is easier all round I know we use Celsius but the bulk of the users here are in the US and you can get faster response if you use fahrenheit
• how are you measuring the engine temp

As noted can you supply 3 readings

1. driving at around 1800 rpm 50 KPH - you may have to use 3rd gear
2. short idle like a traffic light
3. long idle only do this if you are using ODB software to watch your temps - what you should see is a climb then drop as your fan clutch really kicks in

.

 

While I am not a fan of cooling system flushes you might want to investigate this product or something like it .

http://irontite.com/thoro-flush/

 

the boiling pot of water test = doesn’t matter if the entire thing is submerged. You are looking inside of it and beaming the IR gun directly on the internal metal thermostat. You monitor the temp when it starts to open & what temp is when it’s fully open.

All you want to know with the test = when it starts to open & when it’s fully open.

The units Lucky 8 was selling opened, but they DID NOT start to open or open fully like a true 180F thermostat. They are generic el cheapo knock off’s which are incorrectly marked as 180F, but in reality they perform like 190F thermostats.

I never received a single “bad” thermostat to test from anyone, but I’m willing to bet they were simply so cheap they were marked wrong, sold to Lucky8 at probably 10.00 each & then sold for 33.00 like the 180F Britpart 78C unit they had been selling. I bought an identical 180F el cleapo with the freelander mount for 11.00 shipped on ebay & it tested as a 190F. Then 8 months later I ordered the so called Britpart & received a bubble wrap package with the identical el cheapo tossed in it & yep it tested identical to the POS I got off of ebay as en experiment/test unit.

I only trust a true 78C stamped Britpart, white motorad 180F, or an OEM LR grey unit in a LR box. Anything else is honestly crap!

 

Hmm, Ill try and do a drive to the highway tonight and get up to 50mph and see what happens. Ambient temps here are about 50f

 

You know what, perhaps you are right. I have a motorad 180F in my other D2 and it seems to work great. I have a few spares and I am going to swap one out tonight and see if that changes anything. I was under the assumption that some of the aftermarket ones would be "Good enough" but they might just be no good at all.

Ill post with temps and progress a bit later tonight.