Thread: what temperature - watchdog

Hi, I have my sensor at rear spare thread but on the inlet side very near fuel regulator and my range is 74-88 between winter and summer average whether towing or not. Standard auto with EGR removed. Full cooling hoses, radiator and pump are new. with no spotties etc blocking I set mine early at 95 and up it a tad to 100 max.

This driver side appears cooler but I checked the Nanocom and getting similar but slightly higher readings. Hope this helps but I found from reading forums mine is slightly lower than normal conversations here.

We were pedal down locked 4th with two tonne on the back and way west of lightening ridge in mid summer with 42 degrees on external temp button and had the motor running on 88 and I would slow to keep it under 90-92. We all remember that day well as was too hot to stop and I made a comment that the block is only 40 degrees hotter than outside air. Even the water tanks at the end of the day under the van were to hot to shower with. Pretty impressive motor I reckon from this test

Just drive it for a while and monitor occassionally as there will be differences from sensor points. Maybe I have a low thermostat installed and I don't even know it here

I helped a member out with my nanocom and found his engine watchdog with dry sensor at the back of the head was 9c cooler than nanocom reading. So I think the back of the head is cooler.
My dry sensor is on the factory wet sensor housing bolt and reads same as nanocom.
Regards Philip A

Originally Posted by shamirj

hi all,

D2a with Td5 and engine watchdog. this is mounted on rear of cyl head above turbo. new rad, thermostat (not sure which temp it opens at) and re cond head. so all must be in good cond. new hoses as well.

whilst cruising on roads the temp ranges from approx 90 to 100 under normal cruising 100kms speeds, is this normal or should i get a lower thermostat installed. i have the engine watchdog 2nd edition set to 106 for alarm to go off. would like it to be running somewhat cooler hence the idea of fitting a 82 degree thermostat but dont want to pull out the rad for access.

what temp do others record using the watchdog mounted in similar position. cheers

Hi,

That seems a bit hot to me, my V8 runs cooler than that.

I tested my Td5 last week and it ran at 77 round town and about 82 on a run.

Hope that helps.

Cheers Jerry

Anything over about 92 or 94 I think is too hot and shows lack of cooling,
I'd check the existing thermostat it's easy to do if you have a thermometer .
I once had a car with a 98 deg thermostat, can you believe that in Australia?, got rid of that pretty quick.!
But watchdog warns in the fitting instructions about not fitting the sensor anywhere near the turbo or the exhaust pipe. It's a surface temperature measuring device, so its affected by the ambient temp to some degree. When your car is working like towing etc the metal surface temperature on the head near the exhaust is higher than metal inside The exhaust manifold surface temp is probably close to 500 deg C so big radiant heat , big local heat transfer by convection hot air passing the sensor. If you can move the sensor to the back, front or other side of the head, then see how you go.

The temperature on the watchdog is almost irrelevant and may not relate to actual temperature of the engine as its relevance is its rate of change as load/outside temp changes. Depends where the sensor is.

You need to get your engine up to correct operating temp after a long drive. The water temp will most likely be 90 - 100 but depending where the Watchdog sensor is it may only read 70 - 80 degrees - say 75 (this is not a fault in the system as it it reading the temp on the outside of the engine unlike water temp inside). You need to note this temperature and then set the alarm somewhere about 10-15 hotter.

When you drive - then the actual temperature on your watchdog should always be around your noted temperature. Exceptions will be when stopped on a hot day at lights etc when under bonnet temps rise or genuinely engine temps rise. If the coolant system works the coolant temp will rise and fall and so regulating the temp of the engine and if doing this correctly the watchdog temp should be constant.

Watchdog temp is no use to determine the actual temp of the engine so is no use to determine if you have the right thermostat fitted - you will need to be guided by coolant temp for this.

On my V8 101 vehicle at operating temp of 95 coolant temp the watchdog reads 71. On a cool day it will drop to about 68 and on a hot day maybe 75. When stopped at lights or in traffic on a very hot day maybe up as high as 80 as under bonnet temps rise - coolant temp stays around 95. So in normal use if my watchdog goes outside the range of 68-75 I know I may have an issue. Likewise I can often see coolant temps rise and fall as load etc changes and the thermostat opens and closes but the watchdog remains relatively constant highlighting the coolant system is doing its job.

Cheers

Garry

I have the madman hose adaptor temp probe, runs 88c only rising when pushing up a hill, but back to 88c

Your temperature probe/sensor isn't measuring at the same point as the thermostat is. From what I'm reading it's not even installed into the cooling system. It sounds like you are measuring your engines head temperature rather.

If you want to accurately measure the water temperature you require something like this - Coolant Adapter - Land Rover Td5