Time to reach normal engine temp - M59 2.0Ltr HDi ?

[ghost123uk]

From another thread =

Sounds good news. Might be worth checking that the thermostat is working and getting the engine up to temperature quickly - it may be opening early and keeping the motor cool during warm up. Mine would run at the correct temperature, eventually, but when I took out the stat. is was part open when cold.

That made me wonder, roughly how long does your M59 2.0Ltr HDi take to get up to operating temp, assuming this time of year, and commuter driving, ie mostly B roads and stop start (rather than 60mph main road driving) ?

[oilyrag]

Hi John, most bigger diesels tend to be a bit slow to heat up as they aren't doing much work - a couple of miles should see something approaching normal position on gauge. I 'invested' in an infra red heat gun a while back which has been put to quite a few uses from finding a binding brake to checking whether my log burner was up to temp (!) - you can point it at the stat housing/rad hose and see if warm water is getting past the thermostat when it shouldn't, and it is easy to see the temperature at which the stat opens is correct. Very cheap, but does the job http://www.ebay.co.uk/itm/Laser-LCD-IR-I...SwGYVXBjN1
Cheers
Joe

[geoff]

Just so folks are aware the cheaper laser thermometers are only really indicative in terms of temperature and best used for differential testing, the reason for this is that all material types have differing rates of emissivity which affects the temperature reading attained.
The unit linked to above has a fixed emissivity setting of 0.95 which covers the common darker / oxidised surfaces.
Lighter and shinier surfaces won't give as accurate a reading so the way around this is to place some masking tape on the material to be measured and take the reading of the tape, this will then be accurate ( give the tape time to warm up of course ! )
Just for reference I used to work with thermographic imaging before retiring so the above " tip " is a good one and can save money on expensive equipment.

[ghost123uk]

Hey, I've got one of those infra red temperature measuring guns, I will try your method of seeing if the stat is leaky when it should be closed.

Mine takes at least 10, more likely 15, minutes of country lane driving to reach 80 (degrees that is, not MPH lol)

[ghost123uk]

Cheers for that heads up Geoff.


.

[polar]

2.0hdi are notoriously slow to reach normal running temperature as they are very thermally efficient. The subject gets discussed at the beginning of every winter on the French forum.

[geoff]

As a comparison my 1.6Hdi was, on one occasion, started up from cold and left to idle on the drive to attain correct oil change temperature whilst I was busy doing other things and it took an hour to get there, the type of use / engine load / driving style influences hugely the warm up times.
Your 15 mins sounds normal to me.
Old school vehicles would have the radiator partly blanked off to achieve quicker warm ups / less wind chill effect which worked well but I wouldn't recommend those methods on modern vehicles, just in case you were tempted !

[oilyrag]

Geoff,
I didn't think about different surface effect, so a useful bit of info there thanks , but luckily there's nothing shiny under the bonnet of my Berlingo anyway! As you say, they are an indicator rather than a definitive temperature reading - better than touching a brake disc through a hole in the wheel and hearing the hiss as your fingertip makes contact (I've done that, possibly more than once!). Also useful for seeing if the rads indoors need bleeding -cooler at the top than in the middle - the uses are (almost) endless - I reckon a vet could see a use, and keep their hands a bit cleaner in the process (but I digress).

[ghost123uk]

Re infra red thermal monitors thingies.

Over on the VW T25 forum the subject of tyre pressures often comes up as folk often fit very non standard wheels and tyres. Someone suggested using one to measure the temperature across the width of the tyre to determine if the middle of the tyre was warmer than the edges (after a good run of course). I find that it works. A tyre with too higher a pressure is hotter at the centre of the tread than the edges.