Annoying topic: Agricultural Land Reform...

Hello everyone , as you can see, I'm new here, but I've been browsing this forum for quite some time and have received really good and useful tips. First of all, a big 'THANK YOU!!!'

The topic of AGR has been discussed here many times before, and surprisingly, it has been explained in a fairly plausible way.

Now my question:

When the EGR system fails, as I have already read, it increases the back pressure for the turbocharger, which means that the engine has more power at partial load because the boost pressure builds up faster. The turbocharger reaches its operating speed more quickly without the EGR system.
When the engine is cold, it should be warmed up (which makes perfect sense *g*). Warming up the engine is certainly also important for the turbocharger. Less gas with the EGR system active = lower turbocharger speed.
Ist das AGR nun Defekt liegt ja nun schneller der Staudruck an d.h. der Turbo ist schon bei wesentlich geringer Drehzahl auf max. Speed.
Therefore, the concluding question:
Isn't a malfunctioning EGR valve harmful to the turbocharger when the engine is cold during the 'warm-up phase,' because it reaches its operating speed faster or EARLIER, and thus achieves its maximum RPM sooner than with an active EGR system, which is only deactivated in the full load range?

Thank you all - keep it up .

Hi there.

1. It is called "DIE Führung" - and therefore also "DIE Abgasrückführung" .

"Warming up should never involve full boost pressure; therefore, you won't even reach the areas you described."

And if it does, what does it matter to the turbocharger whether it reaches full boost at an engine speed of 2000 rpm or only 2500 rpm?

Generally, your considerations are probably correct, but you will likely find it difficult to estimate the effects without conducting extensive measurements.

A motor that is never started, by the way, has less wear and tear . So, go for a bike ride .

Okay, please provide the German text you would like me to translate into English. I will only provide the translation.

Thank you for the quick response!

Hmm.
Regarding point 1, you are correct (*g*). I probably confused AGR with AGV because AGV should be the relevant valve.

Here's the translation:

'Regarding point 2: It's true that the turbocharger is more or less indifferent to when it reaches its maximum RPM. However, wouldn't a faulty EGR system cause it to spool up faster and therefore reach its maximum RPM at a lower engine speed? This could potentially make cold starts slightly 'riskier'.'


The latter is also worth considering - so, getting married and letting the wife do all the pushing .

Quote:

The latter is also worth considering - so, get married and let the wife take care of everything.

Or get rich and marry someone, and then just ignore the turbocharger. The V10 TDI already has two turbos anyway .


As I said, these are borderline considerations. If you're worried about it, just leave the AGR valve open.

Okay, please provide the German text you would like me to translate into English. I will only provide the translation.

Marry rich... and let them take care of everything.

Border considerations are also important .

In other words:
No one has ever had to replace a new turbocharger as a result of a faulty EGR valve.

schnuffelvieh wrote:

Warming up is certainly also important for the turbocharger. Less gas WITH ACTIVE EGR = lower turbocharger speed.

I consider this to be largely insignificant because the turbocharger will undoubtedly reach operating temperature much faster – many times faster – than the engine itself, coming from the hot exhaust side.

Only within the first ~20 seconds after a cold start do I try (without having thought about it in detail yet) to protect the cold engine -> LDA rules .

Hmm - your statement makes sense: 'Heats up faster than the engine itself.'

However, I'm also secondarily concerned about the oil temperature. Is long-life oil with a viscosity of 0W-30 good or bad? While it's low-viscosity, it should still reach a 'normal' operating temperature. Since the turbocharger is lubricated and possibly pressure-lubricated by the oil, this is also a reason why it needs to be brought up to temperature, as mentioned before. Or is this not really significant in relation to the turbocharger?
I've read – and even seen it myself! *g* – that the oil temperature is still far from 80 degrees Celsius when the water has reached its normal operating temperature. And the water temperature depends on the engine, since the turbocharger is not water-cooled.

So, to put it briefly again: Is the oil temperature secondary in importance regarding the turbocharger, or is it actually important?

Okay, sniffle.

I think you're mixing up the dimensions.

Of course, a scratch isn't bad, but if I dislocated your arm, that would hurt much more. However, concluding from this that scratches are deadly (and must be avoided at all costs) would be an exaggeration.

Eventually, the engine, including the turbocharger and oil, needs to warm up first.
If you handle it too gently, the most you'll get is scratches.
If you keep pushing it, eventually the "arm" will break off.

In this spirit,
With that in mind,
In that sense,
Best regards,
Sincerely,
Kind regards,
(depending on the context)
m,

schnuffelvieh wrote:

Since the turbocharger is lubricated by oil and also utilizes pressure lubrication for its bearings, this is also a reason why it needs to reach a certain temperature, as mentioned before. Or is this not really significant with regard to the turbocharger?

A loader would definitely have problems with honey-infused oil.

However, the exhaust heat from the turbocharger also quickly warms up the oil inside it.
Sure, cold oil will initially be added, but probably at such a slow rate that it can practically reach the bearing temperature.

Or does anyone know any details about the (high-speed?) oil flow rate in the loader?

Here's something I just found regarding oil flow in the turbocharger...

The storage is achieved using floating sliding bearing bushings, or with ball bearings.
Für die Schmierung der Lager und dem Abtransport der Hitze wird diese Lagerung mit Motordrucköl versorgt.

Since the turbocharger is partially equipped with plain bearings and additionally floatingly mounted in these bushings, the pressure will certainly not be low. It's certain that the pressure is not dependent on the flow rate of the medium, and you likely won't have even 1 mm of clearance in the bearing. The gap is filled with 'high-pressure oil' - but if I were to assume that the flow rate is low, it would not be possible to compensate for the heat that the turbocharger receives under normal driving conditions (RS6 turbochargers are sometimes even white-hot) using new, 'colder' oil.While ball bearings lack the floating mounting feature, cooling through lubrication is still necessary.

Okay, sniffle.

Have you ever had your charger outside? Well, I have, and it probably has more than 1mm of play (I quickly put it back in and forgot everything I saw).

"Our diesel turbochargers don't get as hot, which is why we can use a variable geometry turbine (VTG) – because VTGs would seize up in gasoline engines."

By the way, the turbocharger from the Golf 2 TD LLK is water-cooled, if you're interested }.

Okay, please provide the German text you would like me to translate into English. I will only provide the translation.

Have you ever had your charger outside? Well, I have, and it probably has more than 1mm of play (I quickly put it back in and forgot everything I saw).
}

Could this issue be related to the lack of oil pressure circulation lubrication when the system is expanded?
After all, it's floating, and that floating mechanism relies on oil pressure.

I completely agree with Ulf.

The oil flow rate in the loader is so low that there is no risk of a 'cold oil surge.' The oil quickly reaches the operating temperature of the loader, which is usually above 80°C. In fact, under full load operation, not enough fresh oil flows in to cool the bearings. But we all know this, and the topic was about cold starts.
A loader can handle cold oil perfectly well because the very low flow rate always results in a warm/hot oil mixture. What a loader cannot tolerate is absolutely no oil flow at all.

Best regards, Georg.


P.S.: In many ¼-mile vehicles with turbochargers, the oil line to the turbocharger is preheated electrically before the engine starts because the turbocharger is cooled by the engine's water circulation system. There's probably a good reason for that, right? However, this is a completely different league...

Hmm, George. According to your statement, the 'warm-up' phase is less important for the turbo itself and more important for the actual engine.

So, you don't have to worry about the turbo 'spinning too fast' in the lower RPM range (the lower RPM range for me is below 2000 RPM) during a cold start due to a faulty EGR valve?

I believe that the oil temperature doesn't play a significant role because, with sufficient oil pressure, only fluid friction occurs in the turbocharger, and the shaft does not come into contact with the bearing bushings.

Georg-TDI wrote:

Ein Lader kommt also bestens mit kaltem Öl klar, da durch sehr kleinen Durchsatz immer eine warme/heiße Ölmischung vorhanden ist. . .

... and conveniently, hot oil generally flows faster than cold oil:
-> With a cold loader, there is less oil flow, which results in a longer warm-up time for the loader.
-> With a hot charger, increased throughput is achieved along with improved heat dissipation.

@schnuffelvieh (what does your username actually mean?):
So, really focus your main concern on the engine block rather than the turbocharger .