Thread: TDi Thermostat

I have been making the same enquiry know for a couple of weeks, and keep getting told NO. Even in the UK. If you can find one let me know Too PLEASE!

Why ?

I don't know where to get one but I have seen an 82 degree one once so I know they exist

Originally Posted by 1disco

I have been making the same enquiry know for a couple of weeks, and keep getting told NO. Even in the UK. If you can find one let me know Too PLEASE!

Curious to know if your reasons are the same as mine. In my case I find that the temperature rise on the Tdi 300 rises a lot quicker when under load than all the other vehicles I drive. Having the water circulating via the heater core full time doesnt help as its out of motor and back in via the heater core with no cooling. The 1/2 inch hole in the header radiator tank dont help much either.( Blocked mine off, radiator in place, reached own via top radiator plug.) did seem to improve it a bit. Thermostat is new & tested, radiator clean etc.

yes the cooling is marginal in a defender 300tdi. Im pretty sure my thermostat in my 2.8 is one I sourced and has 82c stamped on it. I will try and find out info from it.

The Tridon replacement for the standard Disco 300 Tdi thermostat is a TT388-190. The 190 refers to the temp in deg F which equates to 88 deg C.

What you need to order is a Tridon TT388-180. 80 deg F = 82 deg C

Thanks Ron,

your numbers may be spot on, but be aware when buying a Tridon from your local auto supplier. If you look in the Tridon cataloge they have 2 different spec'd T/stats for the Disco 300tdi and the Defender 300tdi. One is the correct physical size and design (dual) the other is not....

back when I was trying to sort a T/stat I came across this and contacted Tridon, they didnt take any notice.......

Hmm. I just had a look at the Tridon catalogue again. Under Defender, they show the 200Tdi as needing a 54mm dia thermostat. They don't mention the 300Tdi but they show two high flow thermostats, both 54mm in diameter.

Under 200Tdi Disco they show the same thermostat.

The TT388 I mentioned before for the 300Tdi Discovery is 52mm diameter. Did you see also that the aftermarket parts supplier showed the 52mm TT388 for the Defender. Whom do we believe?

So we need to clarify for which vehicle is the thermostat required for starters. I suspect it might be a good idea to pull the thermostat and measure it.

Like you infer, uninformed, the Tridon catalogue is, in my opinion also, now suspect.

I doubt I have a spare thermostat in the garage from the time I owned a 300Tdi Disco.