After a while away (sold TD6 ) thinking of coming back to a TDV8

What puts me off are the turbo issues I've read about...

I don't think I can run to a 4.4, but does the 3.6 have any 'safe' build years, with less problems ?

No....

It's a use and care issue as far as we can tell, have a search around on here, there are several threads on it. There isn't anything inherently wrong with the turbos themselves but it seems to be failing egr valves which can be a main cause of failure, also oil feed/drain problems, the engine needs proper regular servicing. Properly looked after and they can last how you would expect.

Also short journeys are not good for them. They prefer to get up to temperature slowly and cool down properly before being switched off. There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
Fiat 500x 1.4 multiair Lounge 2015
2010 LR D4 Commercial 2.7 TDV6

Like all turbos then........

Mine was lovingly looked after. Longer journeys only. Dealer serviced. Etc. Turbo blew for no apparent reason. Bought a Supercharged  2012 5.0L S/C
Previous:
3.6 TDV8
4.4 HSE
P38 4.6 HSE
Classic 3.9
90 County
Series3 Lightweight

I'd want to remove the egr valves and have them mapped out - as a minimum.

Here's hoping 4.4 tdv8 prices fall a bit, but do we really know if they don't have the same issue ? 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport

NMJ -"They prefer to get up to temperature slowly and cool down properly before being switched off."

I've heard this before. do you mean actual temperature or spinning load? I understand letting the turbo spinning load increase and decrease on start / stop but how do you regulate the temperature drop if indeed you do mean temperature as in heat.

Cheers  405 AB exec seats Baltic and Cirrus
93 RR Classic efi

Remember it's easier to get forgiveness than permission!

Gone in order:
4.4 TDV8 SE - gone to a good home
93 Classic hard dash Plymouth Blue
03 L322 Oslo Blue
2000 Disco TD5 ES Epsom Green
98 P38 Rioja Red
89 Classic Cairngorm Brown

From what I understand, when under load turbos in general generate immense amounts of heat, I always remember the picture of a lotus esprit engine with its turbo glowing white hot.... The idea of allowing them to run at idle for a short while is to let any heat built up in the turbos to dissipate more slowly and reduce the stress caused by the rapid cooling when you simply turn the car off.

I suppose that this is more relevant following a drive where the turbo has been spinning and generating higher boost levels constantly such as a prolonged fast motorway journey, or when towing, rather than popping to the shops. Allowing the turbo to idle for a minute or two after stopping is what I tend to hear is the preffered thing, allowing the heat levels to reduce more slowly rather than driving like a banshee then just switching the car off. This is why some of the more highly tuned turbo cars from Japan have turbo timers on them which will allow the car to idle for several minutes after you have locked the car, allowing the turbos to cool to idle temperature before shutting down.

Whether this makes much difference, or whether the evidence is simply anecdotal, there is certainly no harm in it. I have been doing it for years in all 6 of the turbo cars I have had and have never had a turbo fail. But there is always a first time..... There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
Fiat 500x 1.4 multiair Lounge 2015
2010 LR D4 Commercial 2.7 TDV6

If you switch off when the oil is extremely hot, the residual heat in the turbos effectively vapourises the oil inside the turbo. It can then stick to the turbo shaft (in the form of carbon), impeding oil flow to the bearings

FWIW, never had a turbo failure on any of my own cars

Think I might look at the petrols

Cooling is less of a problem than you think these days and turbo timers are not necessary , the turbo's are cooled by the thermosyphon principle whereby heat from the turbo causes convection currents in the cooling circuit and draws more coolant round . That said there is a lot of anecdotal evidence that the ERG valves need some kind of preventative maintenance . And maybe good luck as well  2008 MY Supercharged
Rimini Red / Jet
four zone climate
remote park heater
and no ugly kid windows.
magnus satis quod turpis satis

But the turbos on a TDV8 are not water cooled

Didn't say they were , just saying turbo heat is dissipated from the turbo's and just as importantly the oil left in them by this cooling effect , It's how all modern turbo diesels are designed , unless of course you have thrashed the nuts off the turbo and then shut off very quickly like ,oh I don't know , every motorway fuel stop anybody would do . The people who make engines have thought this through and have eliminated the need to run down an engine , and if you do need to ; it's a bad engine and there is no evidence the 3.6 TDV8 is . 2008 MY Supercharged
Rimini Red / Jet
four zone climate
remote park heater
and no ugly kid windows.
magnus satis quod turpis satis

Your own 4.2 S/C has an auxiliary coolant pump, to circulate coolant around the engine when switched off, to prevent heatsoak (same principle as allowing turbos to cool down)

Does this make it a bad engine?

Just a couple of quotes from a search on "Turbo Cooldown"

Quote:

Finally when you've finished driving you need to let the oil cool down to a reasonable level before shutting off, otherwise it can coke up on the turbine spindle and cause turbo problems down the line. You can allow the oil to cool by driving gently for the last few miles, or by using a turbo timer to keep the engine running, or by just sitting in the car until it's cooled down. The best method is to drive gently if possible, as the oil will cool much faster with the airflow from the moving car (vs. sitting static on a turbo timer or you sat in it).

Quote:

My understanding is that it allows the oil to circulate and cool the bearings rather than the hot bearings baking the non circulating oil dry, which then does not do the bearing any good when you next start the engine.

Quote:

The official Subaru sticker on the inside of the door on my first Impreza said "allow to idle for 1 minute after high speed driving" or some such. I thought the reason was to let it cool enough so the oil wasn't taken over temperature when it's stopped from circulating?

I was merely pointing out why modern diesels don't need "spooling down " they are built to cope . two pieces of hearsay and two unassociated petrol engines have nothing to add to this whatsoever  2008 MY Supercharged
Rimini Red / Jet
four zone climate
remote park heater
and no ugly kid windows.
magnus satis quod turpis satis

Would this information, direct from Cummins, be satisfactory for you?

http://www.cumminsturbotechnologies.com/ct...Procedures

Quote:

Operating Procedures
Good engine operating procedures are essential to prolong turbocharger life.

Most frequent operating problems

Particular attention to oil system and air system faults will eliminate the two main causes of turbocharger failure. To prevent this Operators/Owners must ensure that :-

1. Air and oil filters are checked regularly to the manufacturer's specifications
2. Engine maintenance intervals are adhered to
3. Engine and equipment are operated in such a way that is not harmful to the life of the turbocharger.

Good operating practices

Operators and owners can help themselves to get maximum service life from their turbochargers if a few good practices are followed:-

Start Up
When starting the engine use minimum throttle and run in idle mode for approximately one minute. Full working oil pressure builds up within seconds but it is useful to allow the turbocharger moving parts to warm up under good lubricating conditions. Revving the engine within the first few seconds of start up causes the turbocharger to rotate at high speeds with marginal lubrication which can lead to early failure of the turbocharger.

After Servicing
After servicing the engine or turbocharger ensure that the turbocharger is pre-lubed by adding clean engine oil into the turbocharger oil inlet until full. After pre-lubing crank the engine without firing (engine/fuel pump stop out) to allow oil to circulate through the full system under pressure. On starting the engine, run at idle for a few minutes to ensure the oil and bearing systems are operating satisfactorily.

Low Air Temperatures & Inactive Operation
If the engine has been inactive for some time or the air temperature is very low, crank the engine first and then run at idle. This allows the oil to circulate throughout the full system before high loads and speeds are applied to engine and turbocharger.

Shut Down
Before shutting your engine down, let the turbocharger cool down. When an engine runs at maximum power/high torque, the turbocharger is operating at very high temperatures and speeds. Hot shut down can cause reduced service life which is avoidable by a minute or two of idling. Most mobile equipment applications include an adequate cooling period during parking or mooring procedures.

See hot shutdown graph.
Hot shutdown graph

Allow your engine to idle for 1-5 minutes to allow the high temperatures and speed to reduce and so prolong the life of your turbocharger.

Engine Idle
Avoid running your engine for long periods in idle mode (greater than 20-30 minutes). Under idling conditions low pressures are generated in the turbocharger which can cause oil mist to leak past seals into the two end housings. Although no real harm is done to the turbocharger, as load is applied temperatures increase and the oil will start to burn off and cause blue smoke emission problems.

There is a recurring theme here. If you cant spot it, I'll highlight it again for you

Quote:

Allow your engine to idle for 1-5 minutes to allow the high temperatures and speed to reduce and so prolong the life of your turbocharger.