PeachParts Mercedes-Benz Forum - Front crank dampener delete?

It is hard for me to imagine anyone actually removing a harmonic balancer from an engine.

PUMPISH said “All our cars runs with a triggerwheel instead the balance wheel and we never had any problem. All cars run over 7000rpm and several of this cars has allready been runing over 3 years. Check DTM 190-2.5-15v , all of them run without balance wheel at 12000 rpm. Balancewheel is made most like a heavy flywheel to make smooter curve of the engine when RPM goes down”.

Where do I start?
- Harmonic balancers do NOT act like a flywheel. Too small in diameter and barely any mass.
- Because a car ran for 3 years, tells very little. What are the bearings like? Did anyone run 2 identical engines (one with damper and one without damper) for 3 years and see what the bearings looked like?

Here is what Wikipedia thinks of harmonic balancers http://en.wikipedia.org/wiki/Harmonic_balancer

Then PUMPISH contiunues with “And about all this talk that you can not replace stock damper and people on the internet allways only "belive" that it does not work and you can damage you crank. I wanna se 1 person who damaged his crank by removing the damperwheel from his Mercedes”.

I agree with PUMPISH that it will be pretty hard to find the Mercedes with the damage crank due to a removed harmonic damper. I would guess that in a run of 200,000 engines maybe 20 customers remove the dampers (who knows, maybe it is really popular to remove balancers and I am completely wrong). That is 0.01% of the engines in a particular long model run would have a removed damper (but could be 0.02% or even 0.03%). The type of person that would remove a damper is going to be the type that is a) boy racer b) forgetful on engine re-assembly. The “A” type will often “blow” an engine and just think it is because of pushing an engine too hard from Turbo/Nitrous and will probably not try to find the root cause. The “B” type can’t remember he left the damper off, so he will not even look for root cause.

In general, I do not think removing a damper will make an engine crankshaft snap in short order. I do think it will make an engine bearings wear in ways you could not imagine. I do think these bearings will wear out quicker. Not for me.

The very good response by WHIPPLEM104 as he had a good and logical response that a damper will not impact performance when he wrote “It is very small in diameter and the effect would be almost impossible to detect. Rotating mass at this diameter does not take very much energy to spin.”.

I also applaud RBYCC response. Very accurate.

The NHRA (the governing body of drag racing in the USA) states that crank dampers are MANDATORY for all drag racers that run faster than a 10.99 ET. That is just about any drag racer you will see on TV or anywhere else. Seems these guys think it is important, and most likely does not affect performance.

I just did a quick Google for NHRA rules on dampeners, and here is the link http://my5ltr.tripod.com/NHRArules.html

The rules do not dictate very much about what goes on an engine, except it states that it is mandatory for a damper (harmonic balancer) to be present. See paragraph 1.1 called “Engine” where the only words in this section are “Only one internal-combustion reciprocating automotive-type, one motorcycle or one snowmobile engine permitted. Motorcycle or snowmobile powered vehicles without reverse may not burnout across starting line. Harmonic balancer meeting SFI spec 18.1 mandatory in any car running 10.99 (*6.99) or quicker. Maximum height of crankshaft centerline 36 inches (914 mm) on O.E.M. trucks; all others 24-inches (610 mm).”

Hot Rod magazine also refers to the NHRA rules for cars that ET less than 10.99. Take a look at this article and search for “harmonic” to see the reference: http://www.hotrod.com/techarticles/nhra_legal_rules_regulations_time_brackets/index.html

You may not have heard of ATI, but they are based in Baltimore, Maryland (yeah!!) and they have about 90% market share on the big boy harmonic dampers (for racecars).
- Here is a link to their main damper products http://www.atiracing.com/products/dampers/index.htm
- Link to ATI “crankshaft vibration dampers 101” http://www.atiracing.com/products/dampers/101/index.htm
- And “ATI damper technology” is here http://www.atiracing.com/products/dampers/damper_tech.htm
- An interesting article about confusion on power pulleys and dampers is located here http://www.atiracing.com/products/dampers/damper_dinan.htm
- An interesting PDF in regards to drag racing and dampers http://www.atiracing.com/pdf/Balancing_Act--Drag_Racing_Action.pdf

If you look around on Google, you will see there are dampers on a huge variety of car engines for the last 50+ years. I can tell you that Mercedes, Ford, Volvo, Honda, Toyota, etc… do not put excess items on their cars unless they are needed. If PUMPISH was correct in saying “Balancewheel is made most like a heavy flywheel to make smooter curve of the engine when RPM goes down”, the manufacturers would have put on bigger/heavier flywheels to make a “smoother curve of the engine when RPM goes down”. OEMs would not waste their money engineering, making, installing, having spare parts, distributing spare parts, training global maintenance teams on harmonic dampers if they were not necessary parts. Or do we think that OEM manufacturers of 4-6-8 cylinder engines of many configurations and from many different countries all got together and did something dumb in a collective manner? Possibly, but highly unlikely.

When cars are made, there is a lot of variation from crank to crank, piston to piston. Each item weighs a little different and has weight distributed a little different on every part. It is interesting to see how much an engine is “out of balance” and therefore even have an impact on the torque induced harmonic vibrations an engine has. Some engines (of the same model) will have more tendency for harmonic vibration than other engines will. Jake Raby is the genius of the VW world, and has supplied some real world information on how far out of balance a crank/pistons/rods can be, and if properly balanced can lower possible contributions to harmonic imbalances. See article here: http://www.aircooledtechnology.com/index.php?option=com_content&view=article&id=73&Itemid=86

In summary, keep the harmonic balancer.