Inline mod. I run 210f going 70mph in 100f weather with the a/c on and 200f with it off. Around 50mph i will run around 198f with ac and 195 without again in 100f weather. I'm trying to figure out why having the ac on may my temps go up so much. Oh btw i used an Airlift coolant tool to fill my coolant system and it works way better than burping th system IMO. Here is a video of a guy using it.

 

I bet the coolant mix has more to do with liners coming lose than engine temps, to much water.

A Rover can with stand temps of 210, 10 miles or 300,000 miles, seen it.

I've also seen slipped liners improperly diagnosed more than you think.

When you pull a truck up to a shop and the rover has a tick or noise, when the mechanic says slipped liner engines junk with out as much as touching it, find a new shop.

 

does atlantic british sell the 180 tstat? if so what is the p/n? i am doing a coolant flush and inspection of lhoses in the coming weeks and would like to source the best possible parts and coolant.

 

What was the reason for this?

Lower temps are obtainable without swapping or mods.

 

Yep I live in the SETX region of TX where it's extremely humid and hot during the summer months. I have seen plenty of LR V8's run 210-215F range max and have zero issues. I am completely happy with the 180F LR OEM soft spring thermostat which has brought the range down to the 188-200F range.

Like I said earlier to cool of a thermostat WILL confuse the ECU and it WILL have side effects. Now on old carb setups with no ECU or O2 sensors the engine is clueless as to the 160F thermostat. On any modern OBDII vehicle it has a specific operating temp range in the ECU and without being able to modify those parameters you will not just have a perfectly happy engine or emission system.

Keep the cooling system checked at all times level, coolant condition, and check for signs of any leaks. If you do that and keep an eye on your normal temp range and watch for any sudden spikes you will be fine.

 

One thing that doesn't seem as often discussed is the radiator. Obviously it plays a big part in maintaining low temps. New OE radiators are $700+... but there are some aftermarket ones from AB, Roversnorth, Lucky8, etc for $200-300. Does anyone have one of these and can comment as to their effectiveness?

My radiator is looking like its due for replacing. The fins are pretty beat up, and the left half (I know weird, it usually fails top to bottom?) is much much cooler than the right (driver side). I can keep my hand on the left when temps are at ~205.

 

My 99 is running 188-200F with a $90.00 Ebay D2 Radiator (previous owner of my 03 D2 parts truck had just bought it).

 

The in line mod gives multiple advantages. More stable temperatures is number 1, but there is the added benefit of ease of swapping thermostats, cost and availability of replacement Chevy style thermostats, and even the ability to run without a thermostat if you are back in the mountains and yours seizes up.

 

My temps are the same as yours only it usually doesn't hit 210 at any time.
Swapping stats is a benefit...

 

Previously replied with O/C temperature readings. Monitored more closely today and closed loop kicked in and temp was 119 F.

O2 sensor temp likely has more influence on fuel loop than coolant temps.

Interested in knowing how the engine ECU varies fuel/MPG based upon ECT and if being "cool" negatively affects my MPG.
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