Thread: What's wrong with my temp gauge?

These things are notorious for playing up and it usually relates back to a bad earth for the instruments.

Can't recall where the instrument earth is, it's in behind the dash there somewhere, but that's where i'd start.

Mine started to climb one rainy day crossing the range here and I near pooped myself as I thought I'd cooked the engine.
Turned the wipers off and the temp dropped

I just couldn't be bothered chasing it so installed a VDO mechanical gauge years ago, it eliminates the problem.
The VDO thermowell screws straight into the OE spot, then the feeler bulb screws into that.

Originally Posted by rick130

These things are notorious for playing up and it usually relates back to a bad earth for the instruments.

Can't recall where the instrument earth is, it's in behind the dash there somewhere, but that's where i'd start.

Mine started to climb one rainy day crossing the range here and I near pooped myself as I thought I'd cooked the engine.
Turned the wipers off and the temp dropped

I just couldn't be bothered chasing it so installed a VDO mechanical gauge years ago, it eliminates the problem.
The VDO thermowell screws straight into the OE spot, then the feeler bulb screws into that.

Rick, I like the idea of that. Where do I get such a thing? Any chance of some part numbers?

VDO part # 180 077 022

52mm OD, 1600mm capillary.
The correct thermowell comes with it from memory and the gauge just slots into the dash, replacing the existing one.
I killed one by having the capillary rub through on an injection line it was cable tied to and it wasn't cost effective to get it repaired so ran the capillary through some corrugated tubing next time.

I also smeared some thermo paste/heat transfer paste all over the feeler bulb before inserting it in the thermowell. Probably just being a pedant, but I felt better doing it

You might have to hunt around for a VDO stockist but most spare parts stores should be able to get them in, might even be a list on the Siemens/VDO Australia website.
I bought mine through an instrument repairer in the nearest large town.

Excellent. Much appreciated Rick.

Rick you are a champ i will be doing the same to the county now

I recently fitted a VDO temp sender and gauge to my Defender. It is much more accurate and was partly prompted by the OEM gauge showing normal until it finally gets to the upper limits. The cause was mud that filled in between the radiator fins and dried.

For those interested I have listed the part numbers below. I purchased mine from Ringwood Speedo's Maroondah Hwy Ringwood Victoria.

Now for the interesting part. The gauge shows 90°C In the morning on the way to work but 95°C on the way home. I've yet to work out why. Any ideas? Its a new thermostat too!

VDO cockpit vision Temperature Guage



Part No. Range
310 010 014 K 40-120°C


VDO Water Temp Sender



Part No. Range Thread
320.002 40-120°C 1/8”-27 NPTF

You will notice that you have to change the connector on the sender wire to a female spade electrical connector instead of the bullet type.

I am pretty sure i have the same gauge in mine. Are you running lights when you drive home?? I find that it shows around 90 (just under normally) until i turn the lights on then it instantly jumps to 95ish then if i turn more things on (ie indicators or windscreen wipers) it goes up a bit more. I'm thinking I have a dodgy earth on the gauge. Yet to investigate however.

Originally Posted by MinniTheMoocha

Now for the interesting part. The gauge shows 90°C In the morning on the way to work but 95°C on the way home. I've yet to work out why. Any ideas? Its a new thermostat too!

VDO cockpit vision Temperature Guage



Part No. Range
310 010 014 K 40-120°C


VDO Water Temp Sender



Part No. Range Thread
320.002 40-120°C 1/8”-27 NPTF

It just might be. I will have to check the earthing on the weekend.