Engine running temp

[stugee]

After removing the thermostat from the back of the block and replacing it with a dummy thermostat the heaters have felt cool.

Tonight on the way from home I set up the diagnostics in the odometer and the engine constantly sat between 85c and 90c I had the climate set to hi and the temp in the cabin barely got warm.

Is this correct running temp or is my PRT thermostat goosed?

[sraddave]

After removing the thermostat from the back of the block and replacing it with a dummy thermostat the heaters have felt cool.

Tonight on the way from home I set up the diagnostics in the odometer and the engine constantly sat between 85c and 90c I had the climate set to hi and the temp in the cabin barely got warm.

Is this correct running temp or is my PRT thermostat goosed?

Mine runs between 96-100 degrees

[SD1too]

... the engine constantly sat between 85c and 90c ...
Although I don't have the 1.8 engine that does sound too cool to me, particularly as the conventional thermostat is rated at 88 degrees. I haven't seen any official figures for the PRT.

Don't forget that if you use 'econ' mode the evaporator won't be cooling the incoming air, which should make the cabin feel warmer if yours is anything like my car.

Simon

[mick160]

Mine runs between 96-100 degrees

Mine too. :wot:

Cool air in the cabin could suggest an airlock but would expect high coolant tempetatures if that was the case.

Could well be that the PRT is knackered.

[vindaloo]

and me :wot::iagree:

[T-Cut]

What colour is the plastic case of the PRT? The colour is supposed to define the nominal setting and relief spring tension. The default for the 1.8T is buff coloured. Yours seems to be running bit low IMO.

You can get buff PRTs advertised for the Land Rover a lot cheaper on eBay.

TC

[stugee]

Its the buff PRT thats fitted.

The temps were fine when it had the 2 thermostats fitted. Makes me wonder if the dummy thermostat was replaced in error at some point if the temperatures started to do what they are doing now!

[stugee]

Is this the correct replacement?

http://www.ebay.co.uk/itm/Land-Rover-Td5-Thermostat-Housing-PEM100990R-/320867874743?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item4ab53737b7

[T-Cut]

It looks the part to me and is the same item listed by Rimmer for the 75 1.8NA engine. Rimmer have the 1.8 turbo as PEM101020 (http://www.rimmerbros.co.uk/Item--i-PEM101020) but that's a black one and certainly different from the one the turbo came with from the factory. I've wondered about Rimmer's listing for years because the stats do not seem to be numbered correctly IMO. The LR PRTs used to be a lot cheaper than the MGR ones, but it seems they're getting more expensive.

EDIT: To complicate the issue, I found this from a Land Rover forum in Oct 2007:
Both Rover and Land Rover have used the natural plastic coloured one which
was off the Range Rover V8 engines cooling system and wasn't as suitable for the K16 application as it perhaps might have been. Land Rover started using PRT in 2000 and Rover in 2003 on some cars. Today the grey plastic one is recommended for use and has been available since 2005 on Land Rover Freelanders. This was a Land Rover development to make the PRT more suitable for the Freelander application.

EDIT2: And there's this of course: http://wiki.seloc.org/a/Pressure_Relief_Remote_Thermostat
This article actually mentions the part number confusion for MGR's buff and grey/black version.

[stugee]

It looks the part to me and is the same item listed by Rimmer for the 75 1.8NA engine. Rimmer have the 1.8 turbo as PEM101020 (http://www.rimmerbros.co.uk/Item--i-PEM101020) but that's a black one and certainly different from the one the turbo came with from the factory. I've wondered about Rimmer's listing for years because the stats do not seem to be numbered correctly IMO. The LR PRTs used to be a lot cheaper than the MGR ones, but it seems they're getting more expensive.

EDIT: To complicate the issue, I found this from a Land Rover forum in Oct 2007:
Both Rover and Land Rover have used the natural plastic coloured one which
was off the Range Rover V8 engines cooling system and wasn't as suitable for the K16 application as it perhaps might have been. Land Rover started using PRT in 2000 and Rover in 2003 on some cars. Today the grey plastic one is recommended for use and has been available since 2005 on Land Rover Freelanders. This was a Land Rover development to make the PRT more suitable for the Freelander application.

EDIT2: And there's this of course: http://wiki.seloc.org/a/Pressure_Relief_Remote_Thermostat
This article actually mentions the part number confusion for MGR's buff and grey/black version.

Why is nothing ever simple! :confused:

Just a thought, the car seems to get up to 86-88°C relatively quickly, it just doesn't seem to get any hotter, does this point to a defective thermostat, I would have thought that if the thermostat was defective the engine would just take longer to get up to temp?

Just reading the link you posted, it could be the cream PRT with the higher spring rate which makes sense as the heater seem to blow warm once the revs are up!

[T-Cut]

I don't see your heater output as a PRT related problem. The relief spring on the buff PRT starts opening when the engine speed is around 2000 rpm. This causes cooled water to enter the system, not warm. So, when the engine's up to say 95C on tickover, if you increase the revs to 2000+ you see the temperature fall a degree or two. I have a Schaaper digital gauge taking the readings from the K-bus, so you can monitor the way the PRT operates very nicely. A fall in temperature is typically seen when the revs increase. It's balancing the heat output with the pump pressure so the temperature is a shallow curve rather than something less desirable. Having said that, your 86-88C still looks too low for any typical running situation. The usual temperature curves run between the mid-90s to around 100C or so. In stationary traffic it will often trip on the cooling fan at 104C. This takes it down to 95-96C very quickly. On the face of it, it appears that your PRT may have a fatigued relief spring.

TC

[stugee]

Update. It would appear my heaters are heating up but not at the passenger side. Will need to keep an eye on the running temp as I haven't used the car for a few days!

So what does half the heaters working suggest?

[T-Cut]

So what does half the heaters working suggest?

The heater matrix is silted up. Very common issue and frequently discussed.

TC

[steveo]

Hi Stugee

My 1.8t operates between 96 and 101 under normal operating conditions and I can confirm the prt is buff coloured

Hope this helps

Regards
Steveo