Some modern cars I've driven have no temp gauge, they have a red light for overheating, and some of them have a blue light for not warmed up yet :roll:

I always struggle with how long to warm an engine up. My manual clearly states not to idle for more than 5 minutes as this contributes to glazing. It also says to idle for 1 minute to lube the turbo before driving. I wait the minute and then drive reasonably until the water guage reads normal and then I just drive normal. However driving reasonably seems to lag the engine more. Is there a good choice?

vk2icj I'd go on the long side of 1 minute, and then drive without labouring the engine. Normal driving within the warm up period is okay, particularly in a 4WD where torque is delivered down low. The key is not to thrash it during warm up.

Idle is very important- but the main reason is to supply the turbocharger with oil. Because the charger is a supplemental external device and the last unit which receives oil.
Don't idle longer than necessary- EGR opens during partial load(including idle) and soot builds up quickly in the intake. I had to scrape out 3-5mm of soot after 100k.
But anything longer than a minute during cold conditions is waste of Diesel.

The shut down prodedure is even more important. You would be amazed to see engine temperatures climbing after shut down!

Water temperature may be ok-but oil temperature will be at a safe operating temperature after the double distance- if you drive without load!

sorry about the boat engine thingy, this thread is titled "myths and fairytails...";) i am adamant that it would still make a good boat anchor if it breaks:mad:

perhaps the engineers should have spent more time modifying the block?
agricultural use in Austria is hardly stop start conditions in an Australian summer.

Deez, would copper head gaskets and a really good low viscosity synthetic oil (changed at same regular intervals) go some way to prevent the VM's dramas?

the toyota boys (in the earlier model 3.0l supras) claim an elimination of blown gaskets while still allowing the head to 'wander'.

and todays modern full synthetics have far greater lubricity at a greater range of temps. they have a lower viscosity for a given application, lubricating internals sooner and evenly spreading heat better.

There's no wally factor on the patrol 4.2 diesel.

The only reason it lasts so long and appears so bulletproof is because it doesn't generate enough power to hurt itself. low boost, low combustion temps and immense exhaust emissions which is why it NEVER saw use in europe.

If you overheat a TD42 you will hurt it same as any other motor. And yes, the TD42 has a very nasty habit of running too warm, there'd have to be hundreds of threads on the internet about it and hundreds of mechanics who reckon they can fix it.

It might be less temperamental than the VM 2.5 in the XJ but there's a big difference in basic design and intended use.

It's all good, bud
-over here they think in fact it is a boat engine,hehehe.

no, copper is simply to soft. You can o-ring the head gasket, but that is race tech and not really cheap, because it's not an ordinary o-ring. It's a nitrogen filled ring and the heads have to be prepared for that.


the "wander" is what kills your head gaskets- because you have 4 of them and pressure of a Diesel is way higher than a gasser- it will "lift" your heads
To prevent that, I switched to ARP studs- the original bolts have to much stretch.
As I already said: the fun gets expensive...

The Synthetic oil has better heat carrier abilities.
I use Mobil1 TurboDiesel 0 W40 during the summer and Mobil 1 Delvac 5W40 in the winter, I can afford to buy it, because I got cheaper 60l drums.
More is less expensive. It is still overkill and I had to reseal the complete engine- it started to drip everywhere.

Be warned!
Before you can use that thin viscosity you have to check bearing tolerances. If the crank is worn out already you get a real dangerous pressure drop!
Rebuilding is questionable.

But you still have to get rid of the oil heat.
The water/oil cooler is not enough to provide sufficient cooling. It also brings heat back into the water circuit- not good at all.

I use an additional oil cooler with 500cm². That seems to be huge, but it is only 10cm by 50cm- BMW uses the same size in their 2.5 Diesels.

Interesting read, it will be interesting to hear what will be said of the humble 4.0 litre petrol....

Wow, 60 litres of mobil 1? That must cost a fortune!!