Disco 2 D2 4.0 V8 Engine Oil, Coolant and AC removal

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tom1979

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Evening all,

Picked up a 4.0 V8 D2 a few weeks ago and going through the usual fixes from previous bodges and also want to give it a good service. I've had a few 3.5 and 3.9 V8's in the past but this is my first D2 V8

Looking at RAVE for the oil specification they give two - one of Low compression engines and one for High compression engines. There is no explanation of which vehicles this applies to. Can anyone enlighten me? One uses 5w30 diesel oil (high comp) and the other 10w40 (low comp).

For coolant they specify the same coolant as for the TD5 - presumably this is just the normal OAT that I use in my TD5's?

I am also looking to remove the air conditioning - this will just be an off road vehicle. I cannot find anywhere any mention of an idler that replaces the AC compressor.

It seems quite sluggish for a V8, anyone have any tips to liven it up?

Many thanks!
 
There’s only one compression ratio for the 3.9 engine that is 9.35:1 either D1or 2, the oil grade is stated in your vehicles owners handbook but 10w40 is okay for that engine if it’s not burning the stuff, my 3.9 has been using that 10w 40 since it left the factory.
OAT antifreeze is what I use and replaced every.

I don’t find the V8 fitted in a D1 or 2 sluggish for what is, but after it’s just a load carrier.
 
There’s only one compression ratio for the 3.9 engine that is 9.35:1 either D1or 2, the oil grade is stated in your vehicles owners handbook but 10w40 is okay for that engine if it’s not burning the stuff, my 3.9 has been using that 10w 40 since it left the factory.
OAT antifreeze is what I use and replaced every.

I don’t find the V8 fitted in a D1 or 2 sluggish for what is, but after it’s just a load carrier.
21 years later the owners manual seems to have disappeared! This is the 4.0 V8 though
 
are you saying the 4.0 and 3.9 are the same engine with subtle differences ? I’ve only seen what rave says.
20w50 Valvoline Vr1 for ngine oil..

And yes the 3.9 and 4.0 are the same, the separation is the crank driven pump of the latter engine, which is much more efficient.

Don't use 5w30..

10w40 isn't recommended, most won't notice any issues until higher mileage.
 
are you saying the 4.0 and 3.9 are the same engine with subtle differences ? I’ve only seen what rave says.
Cubic Capacity is the same, but the D2 Thor engine is more than subtle, if your previous 3.9 engine was in a D1 you will have instantly seen the difference in the two, for a start there’s no distributor on the D2 engine, also Land Rover called it 4.0 just to differentiate between the old and new 1999MY disco, when back in 1998 the D2s were in the showrooms.
 
20w50 Valvoline Vr1 for ngine oil..

And yes the 3.9 and 4.0 are the same, the separation is the crank driven pump of the latter engine, which is much more efficient.

Don't use 5w30..

10w40 isn't recommended, most won't notice any issues until higher mileage.
Suggest U look in the disco 2 owners hand boo, like the D1 there’s a whole range of oil grades listed.
 
It seems quite sluggish for a V8, anyone have any tips to liven it up?
- Check/Replace the air filter
- Check the air intake tube hose isn’t a rats nest
- Clean or replace MAF sensor
- Thoroughly clean both sides of the throttle plate and inside the body
- Thoroughly clean the IAC valve
- Check spark plug condition and gaps at .040”
- Check your HT leads are secured onto both the spark plugs and coil packs
- Check for spark on all 8 cylinders
- Remove the black plastic oil separator piece out of the RH valve cover and clean/replace it
Or
- Totally remove the black plastic oil separator piece out of the RH valve cover, toss it in the bin, THEN remove the black plastic nipple piece from the back of intake manifold and replace it with a metal PCV valve part #V288 and reinstall the hose.
- if you have a dedicated Land Rover diagnostic tester, go ahead and reset the adaptive values for the engine ECU.
 
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The following might help you identify the type of engine on your D2 vehicle -

Capture.JPG
 
For coolant they specify the same coolant as for the TD5 - presumably this is just the normal OAT that I use in my TD5's?
I despise using Dexcool coolant though others seem to prefer it for both the V8 and Td5 engines. I much prefer the Valvoline Zerex G05 HOAT yellow coolant for my Thor V8 (I don't know if Zerex is sold here in England). I've used their Zerex coolant for years in my Toyota Camry (V6) , VW Passat (V6) and BMW X5 (Diesel) with zero issues.
G05 product info... https://sharena21.springcm.com/Publ...2d889bd3/c264d227-0dbd-e711-9c12-ac162d889bd1

I am also looking to remove the air conditioning - this will just be an off road vehicle. I cannot find anywhere any mention of an idler that replaces the AC compressor.
You will need to totally remove the 80mm idler pully for the A/C removal.
If you have don't have ACE you can route the belt like in the below picture but you'll need a shorter serp belt.
ERR6899 is the serp belt LR part number for no ACE/no A/C on a Thor V8.
x40SImE.png
 
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I despise using Dexcool coolant though others seem to prefer it for both the V8 and Td5 engines. I much prefer the Valvoline Zerex G05 HOAT yellow coolant for my Thor V8 (I don't know if Zerex is sold here in England). I've used their Zerex coolant for years in my Toyota (V6) , VW (V6) and BMW (Diesel).


You will need to totally remove the 80mm idler pully for the A/C removal.
If you have don't have ACE you can route the belt like in the below picture but you'll need a shorter serp belt.
ERR6899 is the serp belt LR part number for no ACE/no A/C on a Thor V8.
x40SImE.png
Thanks for that, unfortunately ERR6899 is obsolete at our wholesale supplier. I'm going to try and find the Dayco belt reference and go from there. Edit, just found it, 7PK1766.

20w50 Valvoline Vr1 for ngine oil..

And yes the 3.9 and 4.0 are the same, the separation is the crank driven pump of the latter engine, which is much more efficient.

Don't use 5w30..

10w40 isn't recommended, most won't notice any issues until higher mileage.

It seems that 5w30 oil is for my engine (according to RAVE), and pretty much any other oil is fine too! But if 20w50 is what you recommend then I will go with that. Mileage is around 120k miles. I can get Exol 20w50 mineral oil quite cheaply
 
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Thanks for that, unfortunately ERR6899 is obsolete at our wholesale supplier. I'm going to try and find the Dayco belt reference and go from there. Edit, just found it, 7PK1766.



It seems that 5w30 oil is for my engine (according to RAVE), and pretty much any other oil is fine too! But if 20w50 is what you recommend then I will go with that. Mileage is around 120k miles. I can get Exol 20w50 mineral oil quite cheaply

Rave can be a tad misleading, the auto gearbox rebuild section being among the worst!

You'd be better off filling the sump with cooking oil instead of 5w30 ;)

20w50 is the good stuff, it is an old engine by design :)
 
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