Rising oil level

[HerNav]

Hi, sorry if this has been asked but I cannot find anything.

I have an 07 D40 2.5ltr. I purchased with 126k (freshly serviced) After 2.5k I noticed the oil level had risen and it was starting to get a little noisier.... Sent it back to the dealer. They apparently tested fuel pump and injectors, finding 1 faulty injector and cleaned the others. got it back and from about 1k it started rising again after convincing them it wasn't in my head by taking photos and measurements they took it back in.

I purchased from another branded dealer and they have now sent my Nav to a Nissan dealer. They have reported a leak from a seal on the side of fuel pump (seal being replaced) also they want to re test the injector lines.

So I guess my question is; has anyone had this trouble? And should I expect ongoing issues in the motor because of the diesel having been mixed with the oil?

Thanks!

 

[Old.Tony]

Welcome to the forum.

Yes, it's happened before and it's usually that seal. If the sump is drained, filter replaced, oil refilled and perhaps repeated once more, any remaining diesel will be harmless.

The greater danger is if it's undetected and the level rises enough that excessive amounts of diesel vapour are passed out through the PCV. This will cause diesel overrun which (if you don't stop it) is fatal to the engine.

If diesel overrun does commence, there are two ways to stop it:

1) Block the air intake. With a well-sealed snorkel it's easily possible but NEVER use your hand, it could remove the flesh!

2) Detach the PCV hose from the intake. Not so easy when the engine is revving at 5000rpm+ and the exhaust manifold is radiating so much heat the engine bay fills with smoke. It's a little easier if you have a catch can fitted and mounted at the front of the engine bay.

 

[HerNav]

Thank You Old.Tony!

WOW, I am glad I didn't listen to them! How long between "service' would you recommend?

I have attached a photo of the dipstick, just encase it can somehow help other people. (this is where it got to around 2k after injector replacement and oil/filter change)

 

[bods]

Well at least the bearings will be clean haha. A couple of thousand km would be the most I'd let it do before changing the oil and filter again.

 

[Old.Tony]

Yeah I'd inspect the dip stick fairly frequently until you're satisfied that it's been resolved.

Service interval opinions vary greatly. Some opt for 5,000km intervals on the basis that the oil gets fairly black fairly quickly in a diesel and may not be lubricating as well. However, many have noticed that blocking the EGR seems to have a profound effect on oil colour - it stays cleaner for longer!

Then there's the new cars with 15,000km intervals. Engines aren't vastly different, they still pump diesel into the tank and get smoke out the back, so where do you settle?

The book for mine recommends 10,000km intervals so that's what I give it. With yours though, I'd suggest a close eye on the dipstick levels (measured in the same position with the engine at full temperature but wait about 10 minutes after stopping it for the oil to run back to the sump).

 

[HerNav]

Well at least the bearings will be clean haha. A couple of thousand km would be the most I'd let it do before changing the oil and filter again.

Thanks Bods, I was thinking 1k-2k change just to be sure!

 

[bods]

Good luck with it. Hope it is all ok once nissan fix the fuel leak

 

[HerNav]

Yeah I'd inspect the dip stick fairly frequently until you're satisfied that it's been resolved.

Service interval opinions vary greatly. Some opt for 5,000km intervals on the basis that the oil gets fairly black fairly quickly in a diesel and may not be lubricating as well. However, many have noticed that blocking the EGR seems to have a profound effect on oil colour - it stays cleaner for longer!

Then there's the new cars with 15,000km intervals. Engines aren't vastly different, they still pump diesel into the tank and get smoke out the back, so where do you settle?

The book for mine recommends 10,000km intervals so that's what I give it. With yours though, I'd suggest a close eye on the dipstick levels (measured in the same position with the engine at full temperature but wait about 10 minutes after stopping it for the oil to run back to the sump).

We have a great Nissan dealer close to us who we had spoken to before purchasing just to make sure the type of vehicle would live up to what we wanted (not expecting that this would turn out the way it has) They told us not to touch one that has had the EGR blocked off... Not really sure why this was.

Mine also recommends 10,000km servicing, I had never had a common rail before and was a little shocked that the oil has to be checked at running temperature! Anyway, the oil on the dipstick was at the same level cold and warm... strange....

So I had a call from the dealer today, The Nissan dealer that is repairing it is also changing the injector lines... Apparently there is nothing wrong with them but they may leak when put back in the car... Again, seems strange to me! By the time I get my car back it will be almost new haha! (fingers crossed)

I have owned this car for 12 weeks and 3 of them it has been back with the dealer I love and want it back!

 

[Old.Tony]

Replacing the fuel rail is just being careful. I agree with their action there - the rail supports incredible pressures. I thought my Jaguar was dangerous at 80 psi, then I find out that the Navara doesn't just get to 100psi, or even 200psi. My Navara idles around 4,000psi and is capable of a staggering 30,000psi in that rail.

20,000psi of water jet is capable of cutting through concrete like you're stabbing warm butter with a knife. Replacing that rail is a good move and saves you another potential leak.

EGR blocking isn't actually detrimental to the engine. EGR stands for "Exhaust Gas Recirculation" which is just a fancy way of saying that the engineers have designed your car to suck its own farts. It's designed to reduce the temperature of combustion - and the most common argument against blocking it is that this saves the engine from excessive temperatures at full throttle. It is also illegal to do and the fine if you're caught is something over $13,000.

What's interesting about THAT is in knowing how the EGR system works. At idle, the EGR valve is closed because dampening combustion when the engine is just gently ticking over will stall the engine. At full throttle, when the engine is producing its maximum power and heat - the EGR valve is also closed! It's only actually opened during mid-range throttle.

So the argument about blocking EGR being dangerous actually falls flat when you know how the system works.

EGR will reduce greenhouse gas emissions - absolutely no doubt about that. At high combustion temps (not at the highest range the engine can produce, but "high" anyway) the engine can produce nitrogen oxides. Our atmosphere is 79% nitrogen and nitrogen (being an inert gas) doesn't easily react or oxidise. It takes a fair bit of temperature to make it happen, and EGR does reduce (doesn't prevent) the formation. The question of how much NOx it reduces is still hanging there ... and whether the unburnt diesel (black smoke) being emitted is any better for the environment than a bit of NOx!

 

[steel d40]

Also interesting that VW dodgied the EGR (and got busted) for what purpose? Extending engine life, reducing servicing and improving performance seems the only real explanation. Had mine blanked for 150K. Still running sweet with oil change every 10K.

 

[Old.Tony]

I think the primary reason is performance. Because EGR dampens combustion, each power stroke isn't as effective as it could be, so when measuring power output and economy, a vehicle with active EGR will perform more poorly than a vehicle with the EGR disabled.