Mobil F1 0W40 oil on HDi engine?

Post by **Thunderbird** » 11 Apr 2005, 17:26

Is this a good match?

Kowalski · Post by **Kowalski** » 11 Apr 2005, 18:05

Who knows?
For a Xantia HDI 110 which hasn't been chipped, if it meets the mfrs specs it'll be OK. For a chipped car its a bit of an unknown, are you shortening your service intervals and increasing your oil quality etc?

jeremy · Post by **jeremy** » 11 Apr 2005, 18:12

How long are you going to keep it? What's the mileage likely to be then. What will you get when you sell it?
Use a reasonable quality TD oil! and put your money into something that will produse something positive - like take the wife out!
Complete waste of money unless you intend to keep the thing for ever and even then it probably won't make any difference!
jeremy

madasafish · Post by **madasafish** » 11 Apr 2005, 18:58

I have found Comma semi synthetic oil at £12.99 per 4.5 litres very good and much cheaper.
If you plan to travel 1 million miles in your HDI use Mobil (and spend £000s keeping the suspension and engine belts/pulley being replaced).
if on the other hand you are prepared to replace it at 250,000 miles use Comma:-)
PS is a 0-40 the right spec?

Post by **Thunderbird** » 11 Apr 2005, 20:38

Have done 80.000kms (50kmiles) so far.
Expect to trade it at 200.000kms (125kmiles), in the year 2010, for one of these six-cilinders diesel: Citroen C6 V6HDi, Lexus IS250 (2006 model), or a Merdeces S320CDi (2006 model). [:D]
Till now I have been using Total Quartz 9000 10W/40 or 5W/30 every 10.000kms (6kmiles).
At only 8.000kms (5kmiles) after changing the oil, the engine has lost smoothness and the oil seems to be really burned and old. [xx(] Therefore was considering a better oil than the Total Quartz 9000.
I believe the mobil F1 0W40 is about the same price as the Quartz 9000.
Remember my car is tuned...

Kowalski · Post by **Kowalski** » 11 Apr 2005, 21:29

I doubt that the Mobil F1 will be much different to the Total Quartz 9000, they're both premium synthetic oils. Typically with Mobil you pay for the brand name where as with Comma you pay for the oil.
If the engine oil is looking tired after 5k miles you should be changing the oil long before it changes noticably in performance otherwise 125k miles might be an optimistic lifespan for your engine.
The turbo will run a lot hotter chipped and your cylinder temperatures and pressures will be much higher than standard too, the oil has a much harder life than in a non-chipped car and you live in a relatively hot climate (compared to the UK).

jeremy · Post by **jeremy** » 11 Apr 2005, 21:53

125,000 miles by 2010 isn't much. I tried semi synthetic in my BX TD and thought it was slightly noisier so changed back to ordinary TD oil next time and it did seem smoother.
You want some body in the oil especially in a hot climate os he first figure for starting performance isn't so important as somewhere colder.
If the car seems to have lost its sparkle I should think its something more serious than the name on an oil can!
Incidentally my BX TD has done 197,500 miles and wouldn't seem to have any special treatment so far as servicing goes. Oil consumption - minimal and about the same or less than our 70,000 mile ZX 1.9D. Change both at 5 - 6000 miles or once a year.
jeremy

Post by **Thunderbird** » 11 Apr 2005, 21:54

Kowalski, the summer in Portugal and Spain is really hot. Sometimes the tempearature passes the 40 Celcium degrees and usually keeps well above 30ºC after lunch hour.
Don't know the oil temperature, but the coolant temperature often reaches 100ºC. When that happens, the two fans activated at high speed bring the temberature down to 90ºC.
When working at high temperature the HDi engine becomes a little unstable.

Post by **Thunderbird** » 11 Apr 2005, 21:58

Jeremy, I agree with you - a 10W40 oil will be more appropriate on hot summer, as the startup oil temperature will be about 25ºC.

Kowalski · Post by **Kowalski** » 11 Apr 2005, 22:00

The oil temperature usually gets higher than the water, the oil cools the pistons and the turbos so it can get pretty hot.
Petrol turbos had to have water cooling on the turbos otherwise you got coking on the turbo bearings and a short life for the turbo. If your performance mods take the HDI too far you could end up in the same problems because the turbo isn't water cooled, its oil cooled and the oil cooler isn't massive.
Did you get the same high temperatures and "unstable" engine before you had the car chipped?

Post by **Thunderbird** » 11 Apr 2005, 22:09

Kowalski, yes, especially in the city and hard traffic situatins. The Xantia cooling system is not adequate for hot summer days.
My previous Saxo 1.6 16V had the same problem on Summer while driving in the city; stopped with engine at idle; or while travelling at speeds over 200km/h continuously for more than 10 minutes. Interestingly, at continuous 180km/h it stayed cool.

jeremy · Post by **jeremy** » 11 Apr 2005, 22:32

Your Saxo problem was probably fuel vaporisation which would go away with some airflow over the engine. Diesel won't do the same.
As a matter of interest I wonder if the bearing loads (and probably others) are greater in a HDi than they are on the old TD. My reasoning is that the injection is phased - hence quieter running but also a smoother initial ignition point and so less of a hammer blow on the crank bearings. The HDi engine dumps less heat into its cooling water as it has no pre-combustion chambers in the head. I accept that a hot turbo will dump a load of heat into the oil but this only happens when its running hard which probably isn't very often as I imagine you have speed limits that are about the same as ours and if you keep it running forever you'll be doing about 120!
jeremy

Kowalski · Post by **Kowalski** » 11 Apr 2005, 22:37

The bearing loads will depend on the peak cylinder pressures at full throttle, mechanical injection does phase the injection to a degree but not in the same way that HDI can control and profile it. At lower accelarator settings the loads will be smaller because of the lower compression ratios.
I wonder whether you could change the thermostat on your HDI to improve its tolerance to hot weather. They still make the Xantia in Iran, so I'd expect that they've sorted out any temperature related issues that there may be...

rossd · Post by **rossd** » 12 Apr 2005, 03:42

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"> At lower accelarator settings the loads will be smaller because of the lower compression ratios.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Not in a diesel where the air volume and hence compression ratios are constant surely? (Of course, not including turbo boost)

Kowalski · Post by **Kowalski** » 12 Apr 2005, 04:00

The HDI has a compression ratio of about 18:1, the TD has a compression ratio of close to 22:1.
The HDI turbo wastegate is vacuum controlled, so only the boost that is needed for a given throttle opnening is applied to the engine. The TD turbo is mechanically wastegated so it can (in theory) give full boost even when the throttle is closed, in any case it gives more boost than is needed to match fueling all of the time.
The HDI 110 produces more power and the HDI 90 has no intercooler so it's not entirely straight forward but at part throttle the HDIs will be less stressed which is where the vast majority of their driving is done.