Hi All, this is my second post regarding the temperature of my landrover 200TDI. (1991), (90) I recently posted a thread that spoke about high tempreture whilst on road trips. The advise I kindly recieved was to repalce the RAD.

It was great advice and I really appreciate your help, I have another question, which I would like your expert advise on.

When I replaced my RAD, it was rotten through, when I lifted it out the whole bottom section fell away, so clearly more knackered than I had thought. I drained the system and flushed the coolent until the water ran clear.(only problem is I didn't remove the thermostat). However now, the temperature runs at around quarter of the way up the guage. It sometimes gets near half way when put under load, off roading, long periods in first and second gear.

My gut feeling is that the thermostat may need to be replaced, or is this normal operating temperature for Land Rovers?

Can anyone advise

Thanks JB

That's a good one to answer! A new radiator will obviously improve the cooling efficiency of your engine, and as such, the whole system will run a little cooler, or perhaps a whole lot cooler. My 2.5 N/A runs at between 1/4 and 1/2 all the time, and has recently dropped to 1/4 whilst running down hills! It was running at 3/4 before I flushed the system thoroughly (I also found a blockage).

The thermostat mainly ensures that the engine maintains its temperature (which varies slightly depending on which thermostat you have fitted), and in a diesel engine it is important for efficiency (and heating) that the engine runs at temperature. Obviously too high a temperature and it's going to do some damage.

I would recommend that you replace the thermostat, they're cheap enough and it will more than likely make the difference. It's more than likely that it's sticking open, but generally I wouldn't say that you've got too big a problem on your hands. If it starts dropping below 1/4 you have a problem, because it should be running quite a bit hotter, preferably on the half way mark, or just below. It could also be the temperature sender that's broken, another cheap part to change.

-Pos

200tdi's naturally run cool. It's fine.

My original 1998 rad did exactly the same thing. The fins had corroded away and the cross tubes had dropped until they were resting on the front cross member. It was so delicate that it could not support its own weight when I removed it.
Now my TD5 runs between 1/4 and 1/2 on the gauge with no fan fitted and a bloody great intercooler blocking the new rad.
Problems with the stat normally show up as temp never getting hot (stat stuck open) or temp way to hot (stat not opening).
From what you say it sounds like your stat is fine if the temp is varying but if you have a new one then why not change it.
I changed the rad, the heater matrix, all hoses, and the stat so should have a few years of trouble free use ahead of me. I also used some commercial central heating sludge disolver/remover in my engine for a few weeks before flushing with a pressure washer and putting the new parts on. Probably overkill but I'm happy I got as much crap out of the system as I could.
Winter time will be the big test when I see how hot the heater gets.

Whilst we're on the subject of winter heating, I slept in the back of my 90 last week at a friends party (even though I know its Summer). I used a sheet of MDF across the benches in the back and then put my quilt on top of that (as a matress) and my sleeping bag on top. I actually had a good nights sleep and my 90 seemed to retain most of the heat (even though I can see the floor from the inside in some places). I left the engine ticking over for about ten minutes with the heater on and it was like an oven. Really warm and cosy. It was actually like a treat because my bedroom is permanently cold and drafty. The window is knackered and never closes!

Just thought you'd like to know
-Pos

I have central heating, double glazing, warm quilt, and a kettle but my bedroom is still cold and drafty.
If er indoors aint nagging then shes moaning about something or other.