Renault Scenic 1998

[s7er]

Seaching for right oil for
Renault Megane Scenic 1.9 dTi 1998(diesel, not turbo diesel, don't know what letter 'T' stands for)
From owner's manual:
European countries:
CCMC-PD2 15W40 ACEA B2-96/B3-96
CCMC-PD2 10W40 ACEA B2-96/B3-96
CCMC-PD2 5W30 ACEA B2-96/B3-96
CCMC-PD2 5W40 ACEA B2-96/B3-96
Other countries:
API CF 15W40
API CF 10W40
API CF 15W30
Recommended oil: Elf Prestige Diesel T 15W40
Location Estonia near Finland temp: summer: +15..+25, winter: 0...-20(rarely -30)
Car is mainly used at weekend(shopping) and for road trips in summer (one way 2000+km, at place 1000+km(temp can be up to +35 at summer), back 2000+km approximately 5000-6000km)
Driving mainly about 2000-3000 rpm
Car problems: hard to start(especially when temperature below 0), long spins of starter(spins quite good), blue smoke when started
Current oil Castrol Magnatec 10W40 diesel
Planning to change it to 5W40 maybe starting will be easier but which one?

 

[user52165]

FWIW - temps listed are C, not F.

Are you sure your starting problem is oil related? How many miles (K), condition, etc?

 

[s7er]

Well not for sure about cause of starting problem it was just a guess, but diagnostics at dealer center showed nothing - everything works good.
mileage is about 180000
condition of vehicle is good - if something wrong trying to fix it as soon as possible, all what is needed maintain in time(oil change every 8000 km).

 

[Jim Allen]

If the engine spins fast, that pretty much eliminates the oil. (Slow cranking can inhibit cold starts, but it's rare.

White or gray smoke is an indicator that perhaps the glow system (intake heater if it's a DI diesel or precombustion chamber glow plug if it's an IDI) is not working well, or that there is air in the system. If the probelm doesn't occur at all in wrm weather, that points to the glow/ intake heater system and you should have that rechecked. If it happens at any temperature, that leaves air as the more likely possibity.

Small leaks on the suction side of the fuel system can introduce air into the system. If the car is harder to start the longer it sits, that's a good clue. In your case, when the technician saw the car, it had been started and had been bled of air... no symptoms for him to trace back. We wpould assume he properly checked the glow/intake heater system.

I would test this myself. Run the car and then let it sit in the cold until it has completely cooled off ( 5-6 hours in cold weather at least). You might drive it in the evening and start it in the morning. If it starts well after a few hours of sitting but not after days of sitting, that might be a good indication of air. Try that a few times and if no trouble, let it sit longer until you experience the trouble. If you get trouble right away, you may have a big air leak but it also point bclk to the glow/intake heater system.

I don't know your car at all but the way I test for air in diesels is to install a loop clear plastic line in the low pressure part of the fuel system, just before it enters the injection pump, bleed all the air, then observe it for significant air bubbles. If your diesel is a common rail, electronic system with no injection pump, this will not likely apply.

No matter what, if it's spinning over fast, I doubt it's the oil but it still never hurts to get better cold weather oil flow.

 

[OpelFever]

Given -20c temperatures in winter, I'd use a 0w oil like Mobil 1 0w-40 or Shell Helix ultra 0w-40 for fast cranking and wear protection.

In relation to the starting problem, have you recently changed the air and fuel filters? Many diesel-guys change the fuel filter every fall as it can collect moisture and combined with non-arctic diesel, freeze easily.

A product I've found to be effective is Forte diesel fuel conditioner: http://www.forte-nwe.com/SE/Forte+products/Fuel+System/Advanced+Diesel+Fuel+Conditioner.html

When changing the fuel filter, fill it with the Forte and pour the rest into the tank. It does a good job of cleaning the injectors and pump, often making the engine run smoother too.

 

[s7er]

Thanks for suggestions. At least i know have starting point for solving problem.

Well trying change filters as well when changing oil, so it could be air/glow intake system problem.

BTW, could be used "simple" 0W40 or there should stand "diesel" mark?

 

[Brons2]

Wow, those are really old oil specs that your car quotes. I would think any B3-2001/2004 oils would be fine. Or under 2008 specs the Ax/Bx specs
http://www.acea.be/images/uploads/files/20090105_081211_ACEA_Oil_Sequences_Final.pdf

Confused? Me too. Hard to go wrong with M1 0w40 and it is API CF rated as your specs also allow for.