So I noticed today that my harmonic balancer is doing the wobble. I have read on this forum that the dealers will say that some wobble is normal but I just cant drive the car knowing that it could cause some damage. I want to stay away from replacing with another oem part that is going to fail again.

So I was wanting to get some feedback on the aftermarket balancers, do they give out as well or are they permanent fixes to the wobble problem?
I'm looking at the ATI and also thinking about going with the SLP underdrive one to free up some extra HP.

heres a short video of my car that i shot with my phone earlier

2007 A6 LS2

 

Seems like the Summit C2501 is becoming more popular. I'm about to install one with my A&A kit as it's the one they recommended. From what I've been reading it's a great stock replacement balancer for the money.

http://www.summitracing.com/parts/sum-c2501

 

That balancer is not wobbling enough to need replacing. It looks normal to me. But what is all that racket going on in the background? That's not your engine making all that noise is it?

 

I'll look into this one, thanks

 

I guess it looks worse in person than in the video, So i shouldn't worry about it until it starts making the chirping noise then? The background was the exhaust echoing in the shop.

 

Anyone running the underdrive pulley? Did you get any noticeable HP increases?

 

it doesnt look likes its wobbling like mine was. Or it might just be the angle.

 

I bought a Jegg's from Summit. Pretty sure it is the same HB as SLP.

I didn't see any noticeable difference with the under drive.

 

just to add, that is what mine looks like and it has for the past two years or so, ever since I started paying attention to it

 

Visible wobble isn't a real problem. When you feel a strong vibration at one engine speed (say, 2000 RPM), that's the time to change it. Be aware that some OEM replacements are faulty. I had to have mine replaced twice to cure a bad vibration.

 

where is the vibration felt, through the steering/feet/body?

 

I just cant drive the car knowing that it could cause some damage.

Your fear is unfounded. The worst that's going to happen is that your belts will start to produce a rhythmic "chirp". And that will probably take a lot more wobble than I'm seeing in your video. Now if you want to spend $600 to $1200 depending on who does the work for a problem that may never occur, that's your call.

 

How many miles on your engine?

 

First under stand the two problems of the factory harmonic balancer.

The first is that GM designed the balancer with a band of rubber bonding the inner wheel part, and the outer belt wheel part. In most cases, one of the two start to separate from the rubber, and what cause the wobble.



The second problem is that GM no longer key cuts the crank shaft, so the balancer is being held on to the shaft from spinning on it via the bolt torque alone (read the bolt is a stretch bolt that can come loose).
Note, GM did away with keying the balancer since they are no longer used for timing, but was a mistake, since the key is what helps to prevent the balancer from rotating on the shaft under high torque loading.

So when looking for a new dampener, you want it to be a solid/bolt together type unit from the center to the belt section, with a internal type of dampening (instead of the two pieces bonded to a center rubber section alone instead). Both the ATI and the above listed balancer are these type of outer/inner bolt together units.

Next, you want to either key, or drill rod pin key the dampener to the shaft. This will prevent the dampener from slip rotating on the dampener shaft, and which helps the bolt to stay tight as well.

This is a pinning type drilling kit for the ATI unit, but don't see why it would not work with the summit unit as well.


So back to your unit, and the fact that I am seeing both the center section and the outer belt section both wobbling, make me wonder if the problem is not the bolt coming loose alone. The downfall, to get to the just replacing the bolt (hours of work, including pulling the steering gear rack), your pretty much at the same point that it best to replace the stock balancer since it has about a 50K life at at most (glue used to bond the rubber to the steel parts fails)..

As for under driven unit, what you are trying to gain in small amounts of HP, you are loosing in the rest of the system on the belt being drive slower instead, such as the alternator and such at idle. Such my be a good thing for a track or strip car, but one that will be sitting in traffic during normal driving may too much of a off set instead.

 

Do a search and try to find a report of center bolt coming loose. The first 1100 cars in 2005 had a potential problem with installed torque because of a problem with the machine that did the torquing. It has not been a problem.

Do the same for balancer slipping because it isn't keyed. Again no problems in stock configurations.

As for the 50,000 mile life for the balancer, where did that come from?

Drive it and forget it.

 

I think the problem with OEM is the rubber more than the key.
As hard as the old one came off and the new one went on, pretty sure it is not slipping on the crank.
I don't see that bolt coming loose if you are using a new one and torque it.

Maybe in a race car. But not my DD.

 

I think I am just going to leave it alone and just keep an eye on it to see if it gets any worse since there aren't any vibrations at any speed or any belt slippage.

My car is a 2007 A6 with 69,000 miles

 

I had a similar wobble with no noise (which is probably a mater of time), and since I track my car i want to be as reliable as possible, so switch it to ATI pulley. Zero wobble present now.

 

 

mine is an 07 A6 with 56k