warrior

Well-Known Member
I'm not convinced my 300 tdi temp gauge is reading correct,

Its a 300 tdi defender ( genuie) but had then engine changed for a newer 300 at done point in its life,

I've read that disco sender in a fender will read high, how can I tell which I've got?

Or what resistance reading should I get?

Next step to put my digital gauge on out of tool box from work and go fir a drive,

All is new, head gasket just done snd head tested rads bin changed water pump has bin changed
 
if you have a look they are ringed. 300tdis are green (AMR1425) or black(AMR3321)

black is defenders iirc
 
Just had a quick look, it looks black but it's well set back into the sensor in it that makes sense, not as I obvious an in pictures I've seen on google
 
Just had a quick look, it looks black but it's well set back into the sensor in it that makes sense, not as I obvious an in pictures I've seen on google

mine went faulty,ohms resistance was all over the place, i can measure my new one from cold tomorrow if it helps
 
which temp sender is fitted, there are 2, both have a plastic insert around the terminal

Green is AMR1425

Black is AMR3321

From the web ...

"the temperature sensor ( green top ) will not work with earlier instruments and 200TDI or V8 sensor will not fit in the 300TDI engine, the solution is to use the white top sensor from the little MPI petrol engine no YCP10019 or no 8510273 that goes straight in the 300 TDI and works perfectly no need to change dial or anything.

More likely works when putting a 300TDI in an earlier Defender

This will give -
-middle of gauge 88deg c opening of thermostat

-little over middle 95 fully open thermostat

-full deflection just before red 108 boiling point of 50\50 antifreeze water with cap off

-well into red 120 boiling point of 50\50 with cap on

- the 300TDI alternator runs faster than the 200 TDI one and therefore the revcounter reads about 6% fast.

The solution is replace the 49mm pulley with one from the Range Rover V 8 with AMR 2938 alternator which is 52 mm over the grooves which approx 6 % large , problem solved
This more than likely works when putting a 300TDI in an earlier Defender.
- the rest of the conversion is easy but it is best to use a donor 300TDI Discovery to get all the parts necessary, ie gearbox support bracket for 380 gearbox , exhaust brackets (the chassis locations are the same ) and lots of small parts

-Use a 300TDI engine harness and starter cable and connect the generator to the battery through a 300TDI fuse box "
 
I'm not convinced my 300 tdi temp gauge is reading correct,

Its a 300 tdi defender ( genuie) but had then engine changed for a newer 300 at done point in its life,

I've read that disco sender in a fender will read high, how can I tell which I've got?

Or what resistance reading should I get?

Next step to put my digital gauge on out of tool box from work and go fir a drive,

All is new, head gasket just done snd head tested rads bin changed water pump has bin changed

Fit the sender unit and the gauge from the original engine. They are matched.
 
which temp sender is fitted, there are 2, both have a plastic insert around the terminal

Green is AMR1425

Black is AMR3321

From the web ...

"the temperature sensor ( green top ) will not work with earlier instruments and 200TDI or V8 sensor will not fit in the 300TDI engine, the solution is to use the white top sensor from the little MPI petrol engine no YCP10019 or no 8510273 that goes straight in the 300 TDI and works perfectly no need to change dial or anything.

More likely works when putting a 300TDI in an earlier Defender

This will give -
-middle of gauge 88deg c opening of thermostat

-little over middle 95 fully open thermostat

-full deflection just before red 108 boiling point of 50\50 antifreeze water with cap off

-well into red 120 boiling point of 50\50 with cap on

- the 300TDI alternator runs faster than the 200 TDI one and therefore the revcounter reads about 6% fast.

The solution is replace the 49mm pulley with one from the Range Rover V 8 with AMR 2938 alternator which is 52 mm over the grooves which approx 6 % large , problem solved
This more than likely works when putting a 300TDI in an earlier Defender.
- the rest of the conversion is easy but it is best to use a donor 300TDI Discovery to get all the parts necessary, ie gearbox support bracket for 380 gearbox , exhaust brackets (the chassis locations are the same ) and lots of small parts

-Use a 300TDI engine harness and starter cable and connect the generator to the battery through a 300TDI fuse box "

Where did you copy that from? I've already seen that tonight somewhere eles

Fit the sender unit and the gauge from the original engine. They are matched.

I've owned the Landy for 3 years and have had over heating problems, never boiled over gauge just climbs up and it's random, some days it's ok some days it creeps up,

50 on the motorway about 0.8 bar of boost it will go a shade over half just sits a shade under half around town, push to 60/65 1.1 bar of boost and temp gauge climbs to just over 3/4 then I have seen it and backed off, don't know if it will keep climbing if I keep my boot down, put the heaters on and I don't think its overly hot and it cools down within a mile,
 
Where did you copy that from? I've already seen that tonight somewhere eles



I've owned the Landy for 3 years and have had over heating problems, never boiled over gauge just climbs up and it's random, some days it's ok some days it creeps up,

50 on the motorway about 0.8 bar of boost it will go a shade over half just sits a shade under half around town, push to 60/65 1.1 bar of boost and temp gauge climbs to just over 3/4 then I have seen it and backed off, don't know if it will keep climbing if I keep my boot down, put the heaters on and I don't think its overly hot and it cools down within a mile,

it kinda sounds like it's the actual cooling. next time it gets hot, go and feel your rad for cold spots, top and bottom pipes and make sure you still have fins.
 
How hot should it run in degrees c?


Ie, it will idle up to temp, if I check that and my thermometer it's say 50 deg but my gauge is at half way I have a problem? Should the middle of the gauge be around 85 deg ish?
 
I've installed a VDO system, temp runs at about 90/92 degrees. it has a 88 degree thermostat but the temp sender is before the stat and measures cylinder head water outlet temp. If you are using a thermometer are you putting it in coolant tank? if so then you are measuring water outlet temp from radiator which will be a lot cooler. Use an IR thermometer gun right up against sender unit and that will give you an idea of the water temp the sender is sitting in (and therefore roughly what the gauge should read). Be aware that LR gauge is pretty pants, it was only when I fitted the VDO that I noticed it was running cool (about 78) due to duff stat, LR gauge had always read just right of centre. New stat and temp went up to 90 and the heater worked a lot better too!
 
yeah 88ish

if 50 degrees on a ir therm is halfway then your sender and gauge aren't matched.
 
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Where did you copy that from? I've already seen that tonight somewhere else

It's from LZ somewhere, prolly 300tdi engine section...

I've owned the Landy for 3 years and have had over heating problems, never boiled over gauge just climbs up and it's random, some days it's ok some days it creeps up,

50 on the motorway about 0.8 bar of boost it will go a shade over half just sits a shade under half around town, push to 60/65 1.1 bar of boost and temp gauge climbs to just over 3/4 then I have seen it and backed off, don't know if it will keep climbing if I keep my boot down, put the heaters on and I don't think its overly hot and it cools down within a mile,

Maybe got some sludge or scale on the sender end...
 
I cleaned everything when I did the head gasket so should be clean,

I but my digital gauge on it and!!

Left idling it gets to 56 deg gauge just under half way,
68CE635A-0586-4E06-B22C-C5EFC2C81119.jpg


Then off for a drive up the motorway it got up to, 86/89 deg and hers the gauge,

97E9EA83-FD2A-48E2-A6EC-DAB92E6B27C6.jpg


I suspect my over heating might just be a bad gauge or sender
 
has it just started happening?

a bad earth can allow current to go via the dials and bump them up. try turning your heater blower on full and see if it makes the gauges rise.

earth point is on the bulkhead right of the brake servo
 
has it just started happening?

a bad earth can allow current to go via the dials and bump them up. try turning your heater blower on full and see if it makes the gauges rise.

earth point is on the bulkhead right of the brake servo

No it's been happening since I 1st bought it, well not long after I took it to billing and that's when it happened,

If I turn my heaters on it doesn't change anything, I think I've cleaned the earth up not to long ago
 
Won't be going anywhere this week I smashed the passenger window on a tree and bent the door handle and blew my rear diff to bits need to sort them out 1st
 

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