Trying To Avoid 1.6HDI Turbo Failure

[Bob L'eponge]

Personally I think the sump design is responsible for a lot of the problems with this engine.

The drain plug is on the bottom of the sump and is recessed upwards by about 10-15mm, add to this the depth of the captive threading inside the sump for the drain bolt and I'm guessing you're looking at approximately 20mm of height.....So even with the car totally level and draining the oil per Citroen's instruction you will be left with quite a bit of old oil left in the sump.

I had the same thoughts, but close inspection shows that there is a drilling through the threads allowing the rest of the oil to escape - assuming that it doesn't become blocked of course.

[Bob L'eponge]

I think the best advice if you have a DPF would be to get it removed and have the car remapped, but that goes for all DPF's as far as I'm aware.

There is now an official statement saying that doing this is illegal, and no doubt the MOT will, sooner or later, be tightened up to check for this being done. Personally I think FAP's are great, given all that cancer and asthma inducing rubbish that comes out a diesel engine that doesn't have one fitted.

https://www.gov.uk/government/publicati ... dance-note

[Bob L'eponge]

Some scary / sobering pics in this report...1.6 HDi turbo replacement

Hardly surprising, given that engine was driven for 60,000 miles on just one oil change!

[uncle buck]

I had the same thoughts, but close inspection shows that there is a drilling through the threads allowing the rest of the oil to escape - assuming that it doesn't become blocked of course.

Thanks for that as I hadn't realised it had that.
Still a very bad design as far as I'm concerned and like you mention it could easily become blocked & more than likely does.

There is now an official statement saying that doing this is illegal, and no doubt the MOT will, sooner or later, be tightened up to check for this being done. Personally I think FAP's are great, given all that cancer and asthma inducing rubbish that comes out a diesel engine that doesn't have one fitted.
https://www.gov.uk/government/publicati ... dance-note

It still comes out...it just saves it up and comes out in one go.


Cheers.

[Bob L'eponge]

There is now an official statement saying that doing this is illegal, and no doubt the MOT will, sooner or later, be tightened up to check for this being done. Personally I think FAP's are great, given all that cancer and asthma inducing rubbish that comes out a diesel engine that doesn't have one fitted.
https://www.gov.uk/government/publicati ... dance-note

It still comes out...it just saves it up and comes out in one go.

Cheers.

Not quite, in that the FAP converts all those particulates into C02 gas, which is a lot less damaging to health, as you might expect given that it is the normal product of respiration.

[Mandrake]

Some scary / sobering pics in this report...1.6 HDi turbo replacement

Hardly surprising, given that engine was driven for 60,000 miles on just one oil change!

Where does it say that ? Check again (a new car will have new oil too)

Its a little bit ambiguous (on page 2) whether the indy servicing was all after the dealer servicing or whether there was some interleaving though. Regardless of how its interpreted the intervals are still far too long.

[Bob L'eponge]

EGR blanking, I found out about with a few searches on the subject. The valve puts soot from the exhaust back into the engine oil.

I have seen this claim before, but I feel the degree to which this happens has been vastly overstated. All the EGR does is divert spent exhaust gas back into the inlet, downstream of the turbo and immediately upstream of the inlet valves, and there is no direct path from here to the oil system. If there was such a path everything else in the inlet, including the compressed gas from the turbo, would go the same way.

It has been proposed that the usual route that this 'soot' supposedly takes is via the piston rings. However, how much gas blows past the piston rings in an engine in reasonable condition? This also seems to be a rather circular argument in that if the exhaust gas fed via the EGR is able to blow past the rings, then surely the rest of the exhaust gas would also be able to do the same, so creating exactly the same problem. Then there is the issue that with modern engine management systems, in most running conditions there is likely to be little soot in the exhaust gas in any case.

To be honest, I think that a lot of the supposed problems caused by EGR valves are talked up by those who don't like the idea of there being anything on their engine that does not aid performance!

Similarly, when people report 'gunge' in the inlet manifold this is almost certainly not 'soot' from the EGR circuit itself per se, but oil from a worn turbo seal or whatever, which becomes baked on the inside of the inlet channels by the extra heat from the hot gas introduced via the EGR valve. For even this to happen a lot of oil would have to be floating about. For example, my wife's Nissan Note has a Renault 1.5 Dci engine with almost 200,000 km on it, and it does use a bit of oil, but the manifold certainly isn't full of 'gunge'.

(By the way, the first versions of these engines also had a bit of a reputation for getting a 'gunged up' EGR valve. The design of these valves was modified about 10 years ago but people still seem to think that it is a concern. Probably the same people who think Volkswagens are the most reliable cars and that Italian cars rust. ) Anyhow, I recently serviced her car and thought to check the EGR for 'gunge'. All it had was a light dusting of soot which washed away with a little petrol and a paint brush.)

I would argue that the real problem here, as in many other cases, is not the EGR valve, which plays a vital role in reducing emissions, particularly nitrogen oxide, but other factors.

[Bob L'eponge]

Some scary / sobering pics in this report...1.6 HDi turbo replacement

Hardly surprising, given that engine was driven for 60,000 miles on just one oil change!

Where does it say that ? Check again (a new car will have new oil too)

Well the word 'change' does imply that there was something to be changed, so a car with one oil 'change' in 60,000 miles would have had two lots of oil in total, but only one change of oil. That report does say

Serviced by a main franchised dealer 2 times from new, at every 30,000 miles approx

So in my book this implies that at 59,999 miles it was still running on its first oil change.

Also, the car did 107,800 miles before being stripped, so it seems that those 3 services at an independent dealer at '15,000 mile intervals' must have been done at around 75,000, 90,000 and 105,000 miles. No?

P.s. Another point of note here is that PSA have upgraded the spec of the oil to be used with this motor since 2007. It is quite possible that the change done at 30,000 miles, and perhaps even the factory fill, used semi-synthetic oil, the mineral oil component of which will in no way last 30,000 miles!

[uncle buck]

Not quite, in that the FAP converts all those particulates into C02 gas......

Yes on paper it does....but in the real World !

Similarly, when people report 'gunge' in the inlet manifold and EGR this is almost certainly not 'soot' from the EGR itself per se, but oil from a worn turbo seal or whatever, which becomes baked on the inside of the inlet channels and the EGR valve by the extra heat from the hot gas. For even this to happen a lot of oil would have to be floating about.

Absolute rubbish....

All Diesel engines will have a residue of oil in the inlet manifold, it gets there from the crank case breather pipe that is tapped into the inlet pipe work / manifold. On engines fitted with Turbos fitted this will be tapped into the inlet pipe work before the Turbo on the suction side
Because Diesel engines have high compression there is a lot of piston blow by (a lot more than a Petrol engine), this goes into the crank case and exits via the crank case breather pipe. The exiting fumes pass through an oil separator but this never removes 100% of the oil particles from the fumes so they end up being distributed over the inlet pipe work as a fine oil residue.
Now add dirty exhaust gasses to the inlet manifold from an EGR system and it's obvious what is going to happen....Yes the dirty exhaust gasses are going to stick to the oil residue in the inlet manifold etc.

Make no mistake the thick gunge you see in a Diesel engine manifold fitted with an EGR valve came from the exhaust gasses...nowhere else.


Cheers.

[Bob L'eponge]

Because Diesel engines have high compression there is a lot of piston blow by (a lot more than a Petrol engine), this goes into the crank case and exits via the crank case breather pipe.

Yes, there will be some blow by, but I would hesitate to say 'a lot' on an engine in good nick. And surely what blow-past there is will put dirt directly into all that oil that is flying around inside the crankcases? So it is wrong to think that the EGR valve is wholly, and perhaps even significantly, to blame for putting dirt into the oil, which is pretty much what I argued.

add dirty exhaust gasses to the inlet manifold from an EGR system and it's obvious what is going to happen....Yes the dirty exhaust gasses are going to stick to the oil residue in the inlet manifold etc. Make no mistake the thick gunge you see in a Diesel engine manifold fitted with an EGR valve came from the exhaust gasses...nowhere else.

In the above case I would say that the 'gunge' is not just from the exhaust gas, but is a product of both the oil and the exhaust gas. It also follows that if there is little or no oil there will be nothing for the passing gas to 'stick' to / little oil to be carbonised by the exhaust gases. Crucially, I think that you overstate the amount of oil that will by pass the oil separator and end up in the inlet in an engine in good condition. For example, any such oil will be lost from the lubrication circuit and burnt, yet on my car (and the Fiat diesel that I had before it which had 160,000 miles plus on it) there was no discernable oil use between changes.

Also, the inlet manifold on my car (80,000 miles so far) and my wife's car ( 120,000 miles plus and which does use a little oil), both of which are diesels fitted with an EGR valve, are pretty much 'as clean as a whistle', so it is not universally true that diesels with EGR valves will have 'thick gunge' in the inlet manifold. (Probably, as I have argued, because they are in good condition, without large amounts of oil leaking past the turbo seals, excessive blow-past due to worn bores and so forth).

[Peter.N.]

The oil in the inlet manifold can't come from the turbo as its downstream of the EGR.

Peter

[uncle buck]

Yes, there will be some blow by, but I would hesitate to say 'a lot' on an engine in good nick. And surely what blow-past there is will put dirt directly into all that oil that is flying around inside the crankcases? So it is wrong to think that the EGR valve is wholly, and perhaps even significantly, to blame for putting dirt into the oil, which is pretty much what I argued.

There is always a lot of blow by on a diesel engine, even when they are new.

The blow by does put dirt into the oil within the engine, and because a diesel engine has a lot more blow by than a petrol that's why the oil turns black a lot quicker.

On a diesel engine WITH NO EGR system you will find a film of black oil in the inlet pipework / manifold, this is perfectly normal & I have seen this for years.

On a diesel engine WITH an EGR system you will find a thick build up of gunge that looks like black soil, sometimes this is a dryish consistency sometimes its wet. This has only started to happen since the introduction of EGR systems.

In the above case I would say that the 'gunge' is not just from the exhaust gas, but is a product of both the oil and the exhaust gas. It also follows that if there is little or no oil there will be nothing for the passing gas to 'stick' to (or to be carbonised by the exhaust gases). Crucially, I think that you overstate the amount of oil that will by pass the oil separator and end up in the inlet in an engine in good condition. For example, any such oil will be lost from the lubrication circuit and burnt, yet on my car (and the Fiat diesel that I had before it which had 160,000 miles plus on it) there was no discernable oil use between changes.

Yes the gunge is a product of the film of oil that lines the inlet pipe work / manifold & EGR gasses...that's what I'm trying to tell you.

I'm not overstating the amount of oil that gets past the oil separator...you're assuming how much I mean !

It doesn't take a lot of airborne oil to coat the inlet pipe work / manifold, we're probably only talking about a few tablespoons worth, maybe a bit more with a Turbo engine...this is because the turbo is sucking the air in so it follows it is also sucking the gases from the crank case faster than a normally aspirated engine. It's not uncommon to remove an intercooler and stand it on end to let the oil run out of it, granted we're not talking gallons here but an egg cup full or so.

Also, the inlet manifold on my car (80,000 miles so far) and my wife's car ( 120,000 miles plus and which does use a little oil), both of which are diesels fitted with an EGR valve, are pretty much 'as clean as a whistle', so it is not universally true that diesels with EGR valves will have 'thick gunge' in the inlet manifold. (Probably, as I have argued, because they are in good condition, without large amounts of oil leaking past the turbo seals, excessive blow-past due to worn bores and so forth).

So you have somehow mannaged to buy two diesel cars that both have next to no blow by..... both have EGR systems but neither of them has any oil or EGR deposits in the inet manifold....both manifolds are clean a whistle.....


Can you give me the winning lottery numbers for next week please !


Cheers.

[Bob L'eponge]

The oil in the inlet manifold can't come from the turbo as its downstream of the EGR.

Peter

Not sure what you mean here. Surely, oil from the turbo does reach the inlet manifold where, as part of the inlet charge, it is introduced to the recycled exhaust gas, which itself reaches the inlet manifold via a separate circuit controlled by the EGR valve?

I would agree that deposits in the EGR itself can't come from the turbo.

[Bob L'eponge]

I'm not overstating the amount of oil that gets past the oil separator... It's not uncommon to remove an intercooler and stand it on end to let the oil run out of it, granted we're not talking gallons here but an egg cup full or so.

I had thought that most of the oil that sometimes collects in an intercooler usually comes from the seal on the inlet side of the turbo?

There is always a lot of blow by on a diesel engine, even when they are new. The blow by does put dirt into the oil within the engine, and because a diesel engine has a lot more blow by than a petrol that's why the oil turns black a lot quicker.

So, are we in agreement that when it comes to combustion products getting into the oil, the main culprit is blow-by past the rings, rather than the operation of the EGR valve?

On a diesel engine WITH NO EGR system you will find a film of black oil in the inlet pipework / manifold, this is perfectly normal & I have seen this for years.

On a diesel engine WITH an EGR system you will find a thick build up of gunge that looks like black soil, sometimes this is a dryish consistency sometimes its wet. This has only started to happen since the introduction of EGR systems.

Ok, so here we are talking about a build up of residue in the inlet manifold. I still don't see how any deposits get from here into the oil.

Sorry!

[uncle buck]

I had thought that most of the oil that collects in an intercooler usually comes from the seal on the inlet side of the turbo?

Incorrect....and a very common misconception.
The oil that collects comes from the crank case breather (it gets through the oil separator) it gets sucked into the air intake of the Turbo and blown out through the pipe work from the Turbo to the intercooler and then on into the inlet manifold.

There is always a lot of blow by on a diesel engine, even when they are new. The blow by does put dirt into the oil within the engine, and because a diesel engine has a lot more blow by than a petrol that's why the oil turns black a lot quicker.

So, are we in agreement that when it comes to combustion products getting into the oil, the main culprit is blow-by past the rings, rather than the operation of the EGR valve?

Yes. ....I have never said that the EGR gasses get into the engine oil.


I said the EGR gases cause a build up of gunge in the inlet manifold to which you dissagreed and said:

....when people report 'gunge' in the inlet manifold this is almost certainly not 'soot' from the EGR circuit itself per se, but oil from a worn turbo seal or whatever, which becomes baked on the inside of the inlet channels by the extra heat from the hot gas introduced via the EGR valve. For even this to happen a lot of oil would have to be floating about....

On a diesel engine WITH NO EGR system you will find a film of black oil in the inlet pipework / manifold, this is perfectly normal & I have seen this for years.

On a diesel engine WITH an EGR system you will find a thick build up of gunge that looks like black soil, sometimes this is a dryish consistency sometimes its wet. This has only started to happen since the introduction of EGR systems.

Ok, so here we are talking about a build up of residue in the inlet manifold. I still don't see how any deposits get from here into the oil.
Sorry!

They don't......I never said they did.


May I suggest you read up on EGR systems...just google it and you will see the deposits they cause.



Cheers.