I bought a nice 3072.1 this week. It's not intended for heavy use (hey, I'm a retirement home for vintage Märklin - this one is gonna go on display and it'll be treated like royalty). I changed all 4 traction tyres, which were completely solidified - they fell to pieces when I removed them. But even with 4 new tyres, the grip that this loco has on the track is very limited. When climbing ramps, the drive bogey needs to be at the rear, not the front, in order to get to the top of the ramp. That way, the weight of the train exerts a bit of downward pressure which prevents slipping. When the drive bogey is up front, it starts slipping halfway up. To test pulling power, I compared it to a mid-'80s 3075. The difference is striking. That 3075 has 6 times (yes, 6 times) the pulling power of the 3072 before slipping occurs. The engine of the 3072 isn't the problem, it's strong as an ox. But traction, pure grip, is rather limited. The 3072 weighs a lot less than the 3075 and it's wheel diameter is much smaller. That also translates into less grip.

Did anyone ever try to put some lead into a 3072? Similar experiences?

It's a V100 diesel loco. 3075 is the V160/BR216. Both loco have the same configuration of axles (Bo'Bo) but the V160 is a bigger and heavier loco.

To get some extra traction, adding weight is the best cure. Unfortunately there is usually not so much space around the driving bogie of older Märklin locos, because the motor itself takes up a lot of room. If you can put some extra weight in the driving end it is much better than in the center of the loco, since a hevy weight in the moddle adds up to the load the loco has to pull.

I do beleive the wheel diameter matters, because bigger wheels have more surface in contact with the rails. But of course this has more of an academic role, since you want the loco to look like the prototype. In the eras of steam locos actually the wheels were bigger on express locos, since they had to travel with higher speed, and the mechanical parts otherwise would have to move back and forward with a rather high frequency. Freight locos were slower, and they could have smaller wheels. This allowed for more axles to distribute the weight and allow the heaviest freight locos to travel on railroads with less maximum axle load.

Very nice long train you build it.

And also: how good are your cars rolling? Smoothly?

Thank you, Oscar !!

I knew you would like the composition. The freight train in front is, right to left: 3072, 4628, 4630, 4642, 4645 (3 units), 4654 (from MUNICH !!!), 4613 (two different ones with Ford 12 m and Ford 17 m respectively ... note the loose cars on the back waggon ....), 4629 (2 units) and 4640 (3 units, 2 white. one blue) .

And of course I am taking deep interest in your layout progress, don't worry !!! Your every move is watched !!!!

Regards,

Hans

I have the later delta and recent 37x versions of this engine and can sympathize regarding the pulling power but in different areas. Mechanically they are all identical. Neither of mine have problems pulling a long consist up my 3% ramps pulling a consist like the one shown, well perhaps one or two cars shorter. The old tin-plate Silberling control cabs are especially high in friction due to the mechanism used to actuate the light change. Where the engines do have problems is pulling heavier trains up hill and through turnouts (at the same time), especially the double slip switch (there even on level ground at times.The slider seems to lift the engine up, dramatically reducing pulling power. This will also happen on other turnouts but to a lesser degree. I don't think more weight would do the job, but might give it a try. Interestingly enough, my Roco V80 which is much maligned for it's pulling power does a better job.

p.