Expert Article Suggestion: [Topic]

Hello everyone,

especially @Ulf:

It feels like ages since I last searched the old forum (somewhere in those 11 MB... or maybe extracted somewhere on my hard drives) for information on how to properly break in a TDI engine, and then you, Ulf, presented your method, which worked perfectly for my car.

People often ask about this (not just here in the forum) - what do you think about writing a technical article based on that?

If you like, I could find the texts from the previous thread and post them here as a summary.

What do you think?

Best regards,

Jan.

Jan6K wrote:

. . .after I asked about the meaningful implementation of TDI, you, Ulf, presented your method, which worked perfectly for my car. This kind of question

comes up again and again (not just here in the forum) - what do you think about writing a technical article based on that?

Hi Jan,

When it comes to breaking in a new car, there are almost as many different opinions as there are car models... I wrote to you back then expressing my opinion (which largely aligns with my experiences).

However, I believe that elevating this to a kind of guideline in the form of a professional article, due to a lack of :(established }knowledge base (at least for me), goes too far.

In the "Gute Fahrt" forum, I once asked what actually happens to our engines before we get our hands on them.
} There were answers suggesting that, among other things, the boxes were sometimes already on their way from the factory to the van, etc., during "minor detours," and were either damaged or soiled.

Therefore, a single introductory article alone could not offer the same level of "functional reliability" as other specialized articles.

Hey everyone,


If I told you how things are done in our DC delivery process, where the vehicles are driven across the factory grounds and onto the trains...

but you probably don't want to know that.

Hi,

Hmm... maybe not "technical article," but rather "thoughts on breaking in" or something similar. Because it seems to be working, as your cars and mine show.

@dokatoto: You should write about it... because of the severely damaged LLK (likely referring to a loaner car), I have a rough idea of what can happen before the customer even takes possession of the car.

I also don't understand why the manufacturers aren't taking action to prevent this, because it could easily be proven, and ultimately it only creates costs and damages the image if it results in damage.

Best regards,

Jan.

Hi,
Here in Emden, the Passat has been manufactured for what seems like an eternity. As far as I understand, an external company is largely responsible for the transport of the vehicles from the factory premises to the port (all on VW-owned roads). This company is constantly looking for new employees to help with loading, and they often recruit at the university of applied sciences. This includes the transport from the factory to the port, and depending on the destination, also loading the vehicles onto a ship.
I think one can imagine what happens when an average, not-so-bright student with the intelligence of a cheesecake (sorry, but it had to be said) drives a brand new Passat.
It's probably not the right way to do it, but it's simply the cheapest option.

Best, Andy.

Hey everyone,

I occasionally have the opportunity to observe the journey of a brand-new car from the factory hall to the first parking area at DC in Bremen. I've seen all sorts of variations. Often, there are full-throttle runs (kickdown) where a considerable cloud of smoke (brown-gray) comes out of the exhaust, but also more restrained drives (where a speed limit of 30 km/h usually applies). It seems that the drivers regularly need a burst of acceleration, especially with high-horsepower vehicles. I always find it best when a new car is pulled out of the hall with a tow bar .
They can do whatever they want. If the engine survives, no one will notice, and if it doesn't, then there was probably a material defect...
Regards,

Eike.

Hello.

especially @ Rainer:

Would you consider it useful to post a "getting started" tip online, including some basic information?

To properly break in an engine, aiming for low fuel consumption (meaning minimal internal friction and good compression), optimal performance, and as little oil consumption as possible, you can follow these guidelines.

"1. Each honing process smooths surfaces that rub against each other, even if they are already lubricated. This principle always applies, even though the break-in process is not as strictly enforced as it used to be due to the precision of modern manufacturing techniques."

To prevent the formation of hot spots during the initial run-in period, the operating temperatures should be kept low, meaning avoid running at full power (or, if unavoidable, do so for as short a time as possible, or only for a few seconds).
Attention: At low engine speeds (below approximately 2,500 RPM), TDI engines can deliver almost their full torque even with only about half the accelerator pedal pressed, which can lead to high combustion chamber temperatures. These temperatures should be avoided during the break-in period for the reasons mentioned above.

3. In order to achieve a proper break-in period at the "maximum" stroke (within the elastic limits of the crankshaft and connecting rod), it is necessary to operate the engine at higher speeds, at least temporarily.
Of course, not for such a long duration that the resulting increased frictional heat leads to pressure sores.

4. Based on requirements 2 and 3, the fundamental entry tactic is "allow them to turn, but don't let them pull you in."

In plain language:
Avoid demanding high speeds, especially when going uphill!
Often, briefly (for a few seconds), shift down one or two gears, less than the TDI would normally allow due to its pulling power, and then shift back up. Initially, keep the engine speed up to a maximum of around 3000 rpm.
Starting around 200 km/h, the frequency, duration, and RPM of the "revving" can be gradually increased. However, continue to avoid excessive engine load (= a lot of throttle).
The first Vmax test, which is a longer full-throttle run, should be performed no earlier than approximately 1000 km of mileage, depending on the progress of the break-in period, and preferably later.

Only after that should one gradually transition to the TDI-typical, shift-lazy and torque-oriented driving style[/quote].

Sure, I'm ready. Please provide the text you would like me to translate from German to English. I will do my best to provide an accurate translation.

Since such or similar entry-level tactics are actually applicable to gasoline engines as well, I believe it would somewhat dilute the character of this "specialized TDI website."

Hi Ulf,

I find this approach quite sensible because many people switching from gasoline engines (who start with the mindset that "everything is different with diesel") might be confused by manual instructions like "no more than 3000 RPM" or even absurd statements like "no more than 120 km/h."

Perhaps it would be helpful to add a sentence like:

"At low RPMs (below approximately 2,500), TDI engines deliver almost their full torque even with only a moderate amount of throttle pressure, resulting in high combustion chamber temperatures, which, in my opinion, should be avoided during the break-in period."

If this sounds familiar... it's from you, Ulf, from that old thread .

The "speed table" from back then could also be included.

"Specifically: Avoid full throttle at the beginning, and instead use a throttle response similar to that of a gasoline engine."
"To break in the engine, drive in the lower gears on flat roads or inclines, using very little gas, and repeatedly rev the engine briefly to around 3,000 RPM. After about 300 km, you can rev it up to around 3,500 RPM, and after about 600 km, you can rev it up to 4,000 RPM."

(Quote from late October 2001)

By the way, you previously indicated a distance of 1500 km as the "endpoint":

"After approximately 1,500 km, you can gradually start enjoying the torque and power."
"Enjoy the powerful boost from the low end."

"In my opinion, this sentence also makes it a bit more specific to TDI engines, because the torque peak is something you typically don't find in a non-turbo gasoline engine."

Best regards,

Jan.

Hi Jan,

I have reworked the text above accordingly.

Deleted upon request.

diesel.gustav wrote:

Of your 4 points regarding "breaking in," only one is absolutely correct. "1. Each entry process..." I completely agree with you on that point.

However, I don't agree with you on the other points.

Hello Gustav.

Then just don't make it so mysterious and tell us what you know about the topic – if it can be explained in a relatively short and easy-to-understand way.

Hi Gustav,

I fully support Ulf's request.

For me, the process worked well... but I'm always eager to learn and explore new things.

Best regards,

Jan.

Hello Ulf, hello Jan,

To be honest, I was also a little surprised by the entry tactic described here.

I think we can all agree that driving at full throttle, both at low and high RPMs, must absolutely be avoided, especially at the beginning.

However, I don't think it's particularly useful to run a (newly installed, warm!) engine with a light load at speeds above 3000 RPM. In my opinion, this doesn't achieve a proper break-in effect, because a certain amount of contact pressure is also needed to smooth the surfaces. And especially in areas where the bearings operate in the mixed friction zone (e.g., piston rings, connecting rod bearings), the high relative speed of the insufficiently smoothed surfaces is initially detrimental.
High load at low RPMs is, in my opinion, unhealthy for the new engine, and so is high RPM at low load.
I believe it's important to break in the engine primarily by varying the speed and load (no cruise control!), in order to achieve a similar break-in effect in the hydrodynamic bearings (main crankshaft bearings). At high speeds without significant load, the shaft floats so much that no smoothing effects can occur.

The startup procedures for our hydraulic pumps are similar. First, the unit is brought up to a medium speed (approximately one-quarter to one-third of its maximum speed) without any pressure. Then, the pressure is gradually increased in small steps until it reaches the nominal pressure. Next, the pressure is reduced back to zero, and the speed is increased. Then, the pressure cycle begins again from the start.
That means the load is increased at a very early stage, but not the speed.

I am looking forward to hearing more opinions on this sensitive topic. Perhaps we can arrive at a kind of "ideal warm-up cycle" through this discussion. I am also willing to revise my views if someone can provide a technically sound counterargument to my statements.

Regards,
Alex.

Hi Alex,

As far as I know, the higher RPMs are primarily intended to allow the piston rings to properly seat and wear in along the entire length of the cylinder bore. It's clear that the piston travels a bit further up and down at higher RPMs. The load involved is likely quite insignificant, and if the load is low, it won't put much stress on the bearings, which is what you mentioned.

Best regards,

Jan.

donalexo wrote:

Hello Alex. However, I don't think it's particularly useful to run a (new, warm!) engine at high RPMs (over 3000 1/min) with a low load. In my opinion, this doesn't achieve a proper break-in effect, because a certain amount of pressure is also needed to smooth the surfaces

.

The higher RPMs are intended to extend the break-in period of the piston rings against the cylinder walls as much as possible (as Jan already mentioned).
The compression pressure is generated there by the piston rings themselves.

Quote:

The startup procedures for our hydraulic pumps are similar. First, the unit is brought up to a medium speed (approximately one-quarter to one-third of its maximum speed) without any pressure. Then, the pressure is gradually increased in small steps until it reaches the nominal pressure. Next, the pressure is reduced back to zero, and the speed is increased. Then, the pressure cycle begins again from the start. That means the load is increased at a very early stage, but not the speed.

Hmm, are these also piston pumps (i.e., fundamentally built like a 4-stroke engine), or are they other designs?

Quote:

I am looking forward to hearing more opinions on this sensitive topic. Perhaps we can reach a kind of "ideal warm-up cycle" through this discussion. I am also willing to revise my views if someone can refute my statements with sound technical arguments.

I join .

Deleted upon request.