"sterben" moderne Dieselmotoren noch? | Posts 48+

Hello,

Here's my experience with diesel cars. My first Golf 1, a 1.5L diesel, lasted 275,000 km before suffering a complete engine failure due to overheating. The second, a Golf 2 GTD (JR), reached 317,000 km. It had a cylinder head problem caused by corrosion in the aluminum casting. It had a latent coolant leak from the beginning. I didn't repair the engine due to experiences with the first one. The Golf continued to run for another 170,000 km with a replacement engine, until it was abruptly stopped by a driver turning left. The replacement engine then ran for another 80,000 km in a Jetta without any issues.
I currently own a Passat 1.9 TDI, manufactured in 1998 (engine code AFN), with the original engine, the second mass airflow sensor, and turbocharger, and it has a mileage of 365,000 km. Well, you could say that modern diesel engines "last longer."

Regards,
Peter.

Hello...

I don't know what Volvo does differently, but they've been building a 12-liter truck PD engine with four-valve technology and an overhead camshaft, driven by spur gears, for at least 10 years. It works perfectly and lasts more than five times the lifespan of a car without failures --> maintenance-free .

Best, Olli.

Well, have you also considered that a truck engine might only reach a maximum of 1800 RPM, and that its maximum power is already achieved just above 1000 RPM?

As I mentioned, my Mercedes also has a high mileage and is running well, but according to the on-board computer, it's running at 5300 RPM.
The TDI engines are only now reaching that level because previously, the pumps and the injectors were the problem. However, all of that is becoming more reliable now.

Don't two-stroke engines, due to their different fuel-air mixture process, inherently have a higher rotational speed?

Best regards, WarLord.

Don't two-stroke engines, also known as pre-combustion chamber engines, inherently have a higher RPM due to their different mixture formation?

Greetings, WarLord.

Hello,
What is 'Drehvermögen' in your context?
Best regards,
Günther

Hmm, the ability to spin higher. Or is that another term? (If so, please forgive me).

Best regards, WarLord.

Hello,

@Warlord

I don't think so. My experience, please don't penalize me for the missing license plate numbers, is as follows:

My first car, a Golf II 1.6 TD, revved up like a gasoline engine; it really started to accelerate and become 'angry' above 3000 RPM.

My second Golf III 1.9 TD was so slow; it wouldn't go above 3000 RPM in higher gears, and especially going uphill, it was practically undriveable.

My current SUV combines the strengths of the 1.6 and 1.9 TDI engines, offering unrestricted agility and responsiveness across the entire rev range.

The 1.9 TD and the 1.9 TDI engines hold up well in comparison, as they both utilize the same displacement and, above all, the same stroke.

At high speeds, in both cases, the piston lags behind the leaner oil combustion.
This explains the drop in the torque curve at the top dead center (TD) position.
The very fine atomization achieved with the TDI creates a larger surface area, leading to faster simulated combustion compared to the pre-chamber principle, which is why it remains powerful and agile up to 4500 rpm.

Even if it were the case that the timing belt represents the best possible solution, one could still control the valves directly via pushrods or electrohydraulically.


Hello everyone...

You're not entirely wrong...
AVL and Bosch are actively testing electric-hydraulic valve control systems.
There are already long-term tests available for gasoline and diesel engines.
Perhaps the engine generation after next will already feature this type of control system.
Whether it will be a blessing or a curse remains to be seen...

Regards,
Steve.