Thermostat or Muff needed?

[Suvvey]

Well it's thick in snow outside and the temperature is not getting much above freezing but unfortunately neither is the motor :-. Noticed that since the temperature has plumetted outside I am struggling to get the needle out of the cold white line. The only time this has been able to move off the line is whilst travelling over 50mph on the clear roads and only if able to do this uninterupted. As soon as I slow to below 40mph it drops right back down again :? Obviously being a draughty defender the heater struggles at the best of times but It's barely thawing inside at the moment.

I checked that the fan coupling is letting it free wheel and it is so I'm guessing this is either the Thermostat stuck open or maybe even just to be expected and time to make up a muff for the front? But surely this is more likely the thermostat as what would happen if it really was cold out there (-4 to 0 out there now)?

[suggs]

i take it you have a tdi, its pretty normal for this weather mines the same, i checked my state and its working fine and dumped the coolant and have filled with new antifreeze no airlocks etc nd still runs cold. i asked this on another forum and most tdi owners said theres were the same...

[Suvvey]

Yes, it's a 200tdi. Only replaced the thermostat, pump and coolant 6 months ago so was a bit anoyed that maybe the stat had gone already. Guess this means I'm going to be cutting up some old carpet tonight then :roll:

[trecfive]

Remove the cooling fan and carry it in the back(with the spanner)that will improve it a bit more,when it warms up outside put it back on again, put a post-it note on the dash to remind you if you tow anything to replace the fan.

[Range Rover Blues]

It's simply that your enghine is nit burning enough fuel to keep warm, or put another way your heater is that efficient it overcools the engine.  The radiator is probably not even getting warm.

I had the same in my Cavalier, It was toasty and warm blasting to Hull every day but when I hit the traffic it would cool down significantly by the time I got to work.  In traffic the 'rad barley got warm.

[Suvvey]

I did try it with the heater turned off and it made a little difference but still no where near what I'd expect. I'm sure the boys in LR knew what they were doing but surely the stat should open at a higher temp than it is, to keep the engine at a healthy operating temperature? I am assuming that the sender is on the engine side of the system and not on the rad side :-. Have to admit I can't picture where it is now :oops: My td5 at work never struggles to get warm.

[william127]

id just be glad its not at the other end of the scale :)

[tack43]

I had a simular problem. Took the stat out and it had "82" stamped on it. Replaced with an 88 deg stat which improved it. I now also have a kenlowe fan which has impoved it more.

Rich

[bogie]

Throw the viscus away and go for a elecy fan!

[graham2306]

The electric fans on Misubishi FTOs are brilliant, they have two speeds and fit on a land Rover rad a treat with a couple of brackets fabricated from dexion or similar.

I have one on my Disco 200Tdi engined Defender and this time of year I never turn it on.

[Saffy]

My temp gauge was in the normal temp with the weekends laning and road travels.  Rad muff was fully closed (nothing to do with the cold but to stop Plains sludge blocking rad). I didn't have the heater on at all, and was mostly driving around with window open (eberspacher diesel furnace keeps things super toasty).

But I still think it's worth checking your thermostat as it not unheard off for even a new/recent one to be duff. Further maybe strap a sturdy plastic sack to front grill - see what happens as easy experiment. I still wonder what the effect is by blocking the flow through the intercooler along with rad... overfueling if pump is previously tweaked? seems to smoke more *Dunno*.
Wouldn't ditch a working viscious fan myself, not with a tdi but that topic usually starts a flame war (someone will come along with CAPSLOCK on and say they circumnavigated the Sun without a fan fitted and even got 45mpg to boot ;))  Same vain I do not think leccy fan belongs in an all-terrain vehicle. Seen a fair amount of leccy fans failing to start on trucks during laning days because mostly they are rarely used and get cruded up with the terrain, others are just bad installations.

[Range Rover Blues]

And leccy fans can't shift anywhere near as much air as a viscous.  The engineers at Kenlowe told me NOT to remove my viscous in favour of twin leccy fans.

Anyhoo, another effect of the cold weather is that the air going into your engine is colder, it should make it more efficient but it also chills the cylinder head.

[Suvvey]

Well unfortunatel I've noticed that my average mpg has gone from a healthy 31/32 to 27 so I think the engine is struggling as it never warms up properly. I'm convinced the stat must be open so will get one today. Even if it makes no difference at least I will still have a spare :roll:

[denviks]

i just had the same on my 300 tdi disco..... i swapped out the stat for a 89 degree one and i now have a nice warm heater again.... so much so i need to turn it down now  :lol:

if you change your stat atleast you should have peace of mind its done

[Suvvey]

Well I went to local moto factors today and they didn't have one :roll: Thought I'd try Halford's for a laugh and they did :shock: Only thing is that when I checked it at home it was an 82 degree one rather than 88 and also was missing the sprung flange on the bottom :-k. Bit pee'd off but guess I should off checked before I left, but at least I now had a gasket so decided to did out the old (6 months!) one.
There was a small deposit stuck in the stat but don't think this would of been enough to cause much if any coolant to pass through. Took it inside to test and it seemed fine. Didn't have a thermometer to test it accurately but it seemed to be reluctant to open far even in freshly boiled water.
Any hoo's it's all back together now. Just popped in to have a bite for lunch and then out to give it a test drive so fingers crossed [-o<

[V8MoneyPit]

Didn't have a thermometer to test it accurately but it seemed to be reluctant to open far even in freshly boiled water.

Noooo..... you shouldn't really dump it in boiling water. I understand it can damage them. You should bring the temp up gradually and check it opens before the water boils. in the same vein, ff your car boils for some reason, it is always advisable to change the stat in case it has been damaged.

[Suvvey]

Well maybe it was what the doctor ordered as it seems to be working now :lol: Just have to keep an eye on it when the weather warms up and make sure it doesn't start overheating if I have knackered it.
Got up to just over 1/3 on the gauge which is where it usually sits and didn't deviate too much after that. Definately never got down to the cold mark once it had warmed up and the heater was much warmer (notice I didn't use the word 'hotter' :lol:) although admittedly the ambient temp outside is probably 5 or more degrees warmer than it has been.
On the downside I do now seem to have an issue with the sender or possibly the wire from it as there is now the occasional sudden drop in temp on the gauge that is far too fast to be an actual reading. Obviously I did have a good look around the area whilst doing the stat and I did notice that the sender does seem to move very slightly in it's housing which may be the issue, also the spade connector looked like it could of done with a tighten up and probably a clean. I don't think this was the original problem as I can definately feel more heat from the heater but more likely from me knocking around in the engine bay :oops:

[Suvvey]

My earlier optimism was short lived and probably self induced as I don't think anything really changed much other than maybe a few degrees warmer outside :roll: Decided to give a muff a try and luckily found an old tent bag that was exactly the right size and even came with clips that fitted the grill in just the right way to keep it secure and tight with no modification Infact I was very impressed with my quick handywork (aka 'bodge'). Also it did make a lot of difference during road use, keeping the needle above the cold line and usually around the 1/4 way mark. Unfortunately when I went laning on Sunday in particularly cold weather it struggled to get above the line again.
Yesterday I was lucky enough to have to drop my work Td5 off at our not so local independant LR specialist so bought another stat. Fitted it today and thought I'd take the long way home to see if it got up to temp.
I DIDN'T EVEN GET A MILE FROM WORK before it was sitting on the half way mark AND it was -2 outside :shock: Firstly I thought something was going terribly wrong and it was going to over heat but it stayed bang on half way all the way home no matter how fast or slow I was going and even when I parked up for a while it only dropped a fraction. Now this tells me that the old stat had been duff from the moment I first installed it 6months ago as it would only ever just get off the cold mark by the time I'd done the 4 miles to work in the morning and this was during the summer :doh:
Toasty hot in the cab now :dance: So much so I actually had to turn the heat down by the time I got home. Not a day to soon either looking the weather that is meant to be coming in :twisted:

[pondy653]

Nice one mate,
Thanks for Sunday by the way you did a stirling job.

TC

[bogie]

GO FOR THE MUFF!!!!!!!!!!!!

[zulublue]

I don't run a fan on a 200Tdi, digital stat never goes over 83 enen in the summer, 200's run cool normally

[bogie]

Same here mate!

[mudplugger01]

same here  no fan  200 tdi  100 % veggie oil lol

[bogie]

LAUGHIN WIT YA!!!!!!!!!!!!!!!!!!!!!!