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!!

heh heh ....

I'm thinking the "humble 4.0l petrol" might survive the blitzkrieg but its cooling system might not. ;)


Good stuff deezelweazel .... keep it coming ..... :mrgreen:

i use cat deo in mine

@davesta:
That's what I thought too, but it's less than 50% (320€ incl. tax)compared with a single liter.
Maybe mil. discount does play a role, too.;)
Trust me, I couldn't afford it otherwise.
My first thought was it might be to thin- and I expected rattle of the hydraulic valve lifters but after checking clearances it is ok- not more noise than usual.
It does help while starting.

Maybe you are going to ask why is he using a thicker oil during the winter? Simple explanation: I try to avoid use during winter. Salt on the road is to aggressive. So it's parked the most time in a garage.
Just trying to cut the corners with "cheaper" oil during storage.

@murray: Isn't cat deo an ACEA E5 oil? Good stuff, must be horrible expensive as all CAT stuff.


But after all oil is not the problem in this engine. The oil circuit can and must be used as an additional cooling aid take take off the heat load of the coolant cuirciut!
Do not remove the built in water/ oil cooler. It isn't a real help to get heat out of the engine bcause the heat of the oil is transferred back to the poor coolant layout.
It does help to warm up the oil during cold start.

Remember first heat law: Heat is always transferred from the hot medium to the cold, never vice versa.

You must grab for every advantage you get:
most people don't know:
A silver radiator surface has only 90% of the heat transfer capability of a black one.
So which one are you going to choose the next time? An alloy radiator?
You are just wasting 10% heat transfer...

You can't afford waste of heat transfer, if you want to drive that Diesel!

Do not replace the stock water pump with trick or high flow units. Just make sure it is in good working condition.
High flow also means a short heat transfer time in the radiator. That results in higher heat preload as the coolant comes back into the engine.
This rule is also transferrable for the gasser. ( By the way: It also consumes a lot of hp!)
The second dangerous thing about it is cavitation. The coolant pump starts to add air bubbles at high speeds. Here we go again- bubbles are big trouble.

You don't believe that?
Get a water pump for the electric drill and attach some clear plastic hoses and start to pump water- 1.try: low speed, 2.try: high speed
ups, were do those bubbles come from during high speed?
Caviation!

Do not decrease the amount of coolant- it is also lubricant for the waterpump!
The coolant circuit does contain a lot of different materials.Copper, brass, iron and alloy- not really an ideal combination.
So make sure to keep the coolant fresh- it does also contain corrosion inhibitors.
You need them!

Flush your coolant system! You need an aggressive acid to get rid of the dirt! I already mentioned it, I got a tablespoon of dirt out of the heater only!! It does work afterwards! It is also a welcomed aid during high load conditions. If the needle climbs into the red zone, turn on your heater- you need every assistance you can get.
Windows can be pulled down, by the way...