Pajero Owners Club of South Africa

Gents,

After the wonderful feedback I got (almost a year ago now), when my SWB 3.8V6 needed an oil change – I’m back with another oil question/mystery.

I took my daughter’s new Nissan Micra turbo diesel for it’s first service (15k km) yesterday morning. The oil of choice is Caltex Delo 400 Gold 15W40. On return to my house the afternoon I popped the hood for a quick post service check. My disgust levels (not to mention blood pressure) went into the redline when the dipstick was covered in black oil.

The blessing with a small place like Barberton is you know everybody. I called the owner/service manager to complain about the car not getting new oil at the service. He immediately came to my house and we considered the problem. The gent that did the actual service is a very good friend and I trust him 100% with my vehicles. We asked him about it and he said he was as surprised after the oil change, when he saw how black the new oil was. The oil on the dipstick was “clean” in the sense that it didn’t leave any residue on the fingers when rubbed. The oil filter was also nice and clean and new looking. The owner/service manager doesn’t know what oil the cars arrive with from the factory – except that it is a multi-grade mineral oil.

End result is we arranged for me to return the car for another oil service this morning. I drove to my office first and then to the dealer (15km round trip). I took it in and stood chatting to the techs while they quickly drained the oil and replaced the filter again. New Delo gold went in again. The oil that came out of the motor was pitch black.

Now for the results after the second oil change:
1) The first time we checked the dipstick the oil was black.
2) After a few checks the oil started looking lighter
3) When I arrived at my office (7km later) and checked again, the oil was as clean and clear as my conscience.

What caused this condition (if we accept that new oil was put in during the original service yesterday)?

The tech says he didn’t use the suck-machine, but the drain plug. The Micra requires a specialized tool to undo the plug and the tech had it on hand – so no problem there either. My daughter’s Micra was also the first(only) “new generation” diesel Micra they had serviced – so they have no experience to fall back on. The incident is going to be logged on their system though.

I paid for the extra oil and filter – because I firmly believe they did replace the oil and filter at the service. After some discussion a decision was taken to run the car for the next 15k km and then do a Delo Gold change again, if the new oil goes black we will replace it with full synthetic oil. The other consideration is to reduce the service distance, I quite like a 7.5k km interval – like my DiDs used to have. Problem there is the inconvenience to my daughter who lives in Witriver.

Is it possible for the new cars to arrive with such rubbish oil that the Delo goes black immediately as it tries to clean up the mess?

Any thoughts or advice will be most welcome.

My pajero gets 10'000km intervals.

I use delo 400 Multigrade - NOT the gold one.

It turns black immediately after an oil change.

However, I spent a bit of extra money on the last change. I drained the oil, poured in new oil, ran it for 5 minutes, drained the new oil and put new oil in again. The oil stayed golden on the dipstick for about 600km.

But, rule of thumb is that a diesel's engine oil will be black after an oil change unless you use extremely short intervals to flush the black oil out.

remember that the colour is not an indication of a problem. The oil will still work regardless of colour as it is working as it should keeping the muck in suspension.

My previous pajero, passat and jetta (all petrol) had golden oil through the entire 10'000km oil change intervals.

pajero + jetta - delo 400
passat - shell helix fully synthetic

Oil that turns black is an indication that the oil is doing its work!
If there is sludge in the engine (due to bad oil or infrequent services), the Delo will dislodge the sludge, which will be evident in the oil (black colour).
The larger particles of the sludge will be caught in the filter.
The filter might have to be replaced sooner than usual, until the Delo has de-sludged the engine.

Diesel engines' sump oil turns black very soon, petrol engines take a bit longer.

If the oil stays clear for a long time, it does not necessarily point to good oil!
On the contrary, it could be oil which does not keep residue in suspension, which means it will settle somewhere to form sludge!

Delo Gold is good, but Delo 400 is the best!

This is my camshaft (oil condition) approximately 2000km after last change.

NB : Last change was a drain, fill with fresh oil, run for 5 minutes, drain again and fill with fresh oil.

The reason I ran the little Micra to my office and back before the second oil change was for the flush effect.

I am aware of oil turning black due to it's cleaning activities . What threw me was the immediate reaction of the Delo Gold as it hit the motor - a new(15k) motor at that. If it was an old motor, with a mysterious service history, I would have understood the immediate reaction.

Do you gentlemen think the following service; Delo Gold on Delo Gold will have the same immediate blackening effect?

On the bright side: where the 3.8V6 sits on 16L/100km after a office and home return run, the little Micra sits at 4L/100km - WOW!

RoelfleRoux wrote: Do you gentlemen think the following service; Delo Gold on Delo Gold will have the same immediate blackening effect?

Only time will tell!
Some engines are more prone to sludging than others. The Nissan / Renault engine might just be one of them.
What I would suggest is an intermediate oil filter change (between the two services).

'Black' oil is not necessarily a 'bad' thing.
Bad oil is!
A blocked oil filter is even worse!

Gerhard,

Getting the Micra to a dealer for a service is quite a schlep for us, that is why the 7.5k interval is second choice at the moment. I'd rather go full synthetic at twice the price, but half the frequency.

Like you say, time will tell - the Micra runs its little tail off all over the Lowveld, where it helps the daughter with her work, so I don't think it will be a long wait.

Any form of Diesel oil will turn black soon after being changed. The reason for this is Diesel oil has a carbon break down effect. This is also the reason oil changes are supposed to be done more often on Diesel engines than they are done on Petrol engines.

black oil is normal for a diesel. It goes hand in hand with the combustion properties of a diesel.

The reason for shorter oil change intervals is due to the sulphur in the diesel. The blowby past the rings of the sulphur's combustion acidifies the engine oil and over time breaks down the properties of the oil.

That is why old diesel (5000ppm +) required 5000km oil change intervals or less and modern european diesel (less than 5ppm) can go up to 20'000km oil change intervals and beyond.

I agree with you gents,

What had me worried was the speed with which the new oil went black - it was immediate. When the tech pulled the dipstick for the first check - even before the motor had started - the oil was already pitch black. He was also surprised and called a fellow tech over to show him as well.

The second batch of Delo didn't turn black at all on the first day. I haven't seen the little car again, so have no idea how long the oil remained clear.

It is still my opinion that the original oil was badly contaminated and left too much contamination behind after being drained. I'll wait for the next service and see how Delo Gold replacing Delo Gold manages the contamination issue.

This incident just adds fuel to my opinion that new cars should get a first oil change soon after being commisioned - like in the good old days

When I follow Marius over to the dark German-underbelly side of motoring (and if it happens to be a new one) I'll insist on an early lube change.

Oh the joy of driving a V6 petrol machine - the Pajero oil is still a clean honey colour after 7 000km of use.