Eccentric Bolts on Weltmieter Sway Bar

William Miller · 04-29-2005, 06:44 AM

I installed their adjustable sway bar on my 83 911.
On the right side, one of these bolts snapped on installation with little torque.
Much less then the 45 ft.lbs specified.

I got a replacement and all seemed fine.

Yesterday when I was home, my brother noticed something hanging down. It was the likage from the left side.
The left bolt broke.
Since installation I did have a full alignment done, so it's possible it could have been stressed. Since the alignment I did go to HPDC.

I've ordered replacements because I need to get back on the road.
I am concerned that this will happen again.
The original eccentric bolts seam a lot stronger and of course they arn't attached to the sway bar.

I don't think the weltmiester bolt is as strong and I don't think the torque setting is as high. It's probable that the alignment guy torqued it to factory specs. Also possible that it was bad metal.

I'm just looking to see if others have had this experience. What's the solution? Is there a better place to connect the sway bar links that will work with the weltmeister bar. It appears there is another weak area in the design. There is 5/16" bolt that goes thru the bottom eye on the link and screwes into the eccentric bolt. 5/16 seem small, but it appears that that bolt is hardened.
It doesn't seem like it's enough metal to twist the 22mm sway bar.

Thanks for any comments or ideas!

Jeff Alton · 04-29-2005, 07:21 AM

Does this setup use an eccentric with a hole that the upper link bolt passes through, or is it an eccentric with a stud sticking out of it to mount the drop link on. It it is the one with the stud, my suggestion would be to locate a new eccentric, like the ones available on quality sway bar kits, that have a hole to allow a hardened bolt to be bolted through it to fasten the drop link. Chuck at Elephant Racing should be able to help you out with two, I think.

Jeff

HarryD · 04-29-2005, 08:37 AM

Bill,

Similar thing happened to me when I was assembling the parts. I was tightening the nut on the eccentric and it stripped. Wanting to get on the road, I brought it to my machine shop to get it turned down and rethreaded. To make a long story short, they ended up machining a new one from stock since the original piece has a hard spot (piece of ball bearing maybe?) in the cast metal used to make the piece. The shop's cutting tool jumped when it hit it and cut the rest of the piece.

As in most things, you get what you pay for and Weltmeister is, unfortunately, a lower cost supplier.

William Miller · 04-29-2005, 08:50 AM

Thanks, I'll look into those Ideas.
I think I've seen someone mount them to somewhere else other than the eccentric. Maybe it was one of the 3 bolts holding the bannana arm and the spring plate together.
I wonder why they didn't use the location on the bannana arm for the stock sway bar. When I take a closer look it will probably be obvious!
I'll take a look at some other bars and see how the hardware is mounted.
Any other ideas are greatly appreciated!

Jeff Alton · 04-29-2005, 09:25 AM

The eccentric mounting location gives a better angle with the sway bar, especially if the bar is adjustable and you move the link forward to stiffen the bar.

Jeff

William Miller · 04-30-2005, 06:37 AM

Thanks!
I'm going to look into these ideas. I went to the elephant racing site, but didn't see parts listed. I'll contact them when I get some time.
It seems their drop links are longer, but that might just be the picture.

89911 · 04-30-2005, 08:52 AM

From what I've seen, the Weltmeister hardware is severly underdesigned for the stress they incur. I've had these bolts snap repeatedly until I switched bars to SmartRacing.

Shown is AJUSA brand bolts shear, similar problems.

Jeff Alton · 04-30-2005, 10:21 AM

Just PHONE Chuck at Elephant, and I am sure he can help. The other option is to grind off that "stud" and center drill the eccentric and put a bolt (hardened) through it. That should only take a few minutes with a drill press.

Jeff

HarryD · 04-30-2005, 12:19 PM

Quote:

Originally posted by 89911
From what I've seen, the Weltmeister hardware is severly underdesigned for the stress they incur. I've had these bolts snap repeatedly until I switched bars to SmartRacing.

Shown is AJUSA brand bolts shear, similar problems.

You are saying that the bolt that connects the drop link to the eccentric sheared off. To me, that is indicative of a mis-specifed bolt strength.

What bolt grade was used for this service? I would think a grade 5 would be normally spec'ed but a grade 8 may be needed for severe applications. Here's an article of unknown quality for your reading pleasure on this topic http://www.rockcrawler.com/techreports/fasteners/index.asp.

If the Weltmeister casting was the weak link, I would have expected it to shear at the threaded end that goes through the springplate.

William Miller · 05-01-2005, 03:54 AM

Just to clarify, mine snapped on the casting. Right at the point that the off centered threaded portion meets the encentric portion. The first time was when I was tightening it up. It seemed to me like it was bad / weak metal. I don't think I got the specified 45# on it. It was before I put the torque wrench on it, so I'm not sure. The bolt in my kit appeared to be a hardened bolt. It didn't snap yet.
The second side snapped when the car was on the road, I know for sure that I did not overtourque it, although I had the car in for alignment and it could have been over tourqued and weakend and then snapped later when driving.

Before posting this thread, I already ordered replacements and they should be here Monday. This time I'm going to install them very carefully and then see how long they last. I think it's only fair before I bash them too much. I do still think that it's a weak link and could have been designed or made better without raising the cost much.

In the mean time, I'm looking for alternatives. Hopefully I can find one without spending huge money on a complete new setup.

HarryD · 05-01-2005, 08:08 AM

Quote:

Originally posted by William Miller
Just to clarify, mine snapped on the casting. Right at the point that the off centered threaded portion meets the encentric portion. The first time was when I was tightening it up. It seemed to me like it was bad / weak metal. I don't think I got the specified 45# on it. It was before I put the torque wrench on it, so I'm not sure. The bolt in my kit appeared to be a hardened bolt. It didn't snap yet.
The second side snapped when the car was on the road, I know for sure that I did not overtourque it, although I had the car in for alignment and it could have been over tourqued and weakend and then snapped later when driving.

Before posting this thread, I already ordered replacements and they should be here Monday. This time I'm going to install them very carefully and then see how long they last. I think it's only fair before I bash them too much. I do still think that it's a weak link and could have been designed or made better without raising the cost much.

In the mean time, I'm looking for alternatives. Hopefully I can find one without spending huge money on a complete new setup.

Bill,

Sound like your failure was like mine due to the low quality material used for the casting. An alternative may be to bring the unit to a machine shop and have them make you a set of duplicates out of tool steel.

911pcars · 05-01-2005, 10:05 PM

In regards to the snapping bolts, I would suspect counterfeit bolts and/or overtightening. Try sourcing them from a reputable fastener supply house. Socket head bolts are the strongest, off-the-shelf fastener one can commonly obtain - typically around 160,000 psi strength whereas Grade 5 is around 120,000.

The socket head bolt is borderline in terms of size (5/16"). I would much rather see a 3/8" (or equiv. metric) bolt to make this connection to the suspension. Yet I still have the 5/16" fastener still intact on my rear setup. Tarret uses a larger bolt as part of their drop link setup. The bolt clamps on their eccentric with a nut. If they or Chuck are able to sell you just the eccentrics, let us know.

Sherwood

304065 · 05-02-2005, 03:38 AM

The other point that hasn't been mention is the ABSURDITY of having to use a 5/16" SAE bolt instead of a METRIC bolt. Now you have to carry an SAE wrench for the ONE bolt on the car! Also, for a bolt mounted in single shear that's going to be taking huge loads from the suspension, I think 5/16" is a little small.

I just bought these eccentrics from Performance Products when I re-did my rear suspension, they were not that expensive, though, so you could carry extras and bolts to the track.

My solution? I'm saving my money for Smart Racing bars.

jaydubya · 05-02-2005, 06:26 AM

Sorry for my ignorance but where exactly does that bolt go? Front or rear sway bar? I don't remember seeing anything like that on my charlie bars.

304065 · 05-02-2005, 06:37 AM

It's the toe eccentric, goes in the forward hole on the spring plate.

89911 · 05-02-2005, 06:42 AM

Quote:

Originally posted by john_cramer

My solution? I'm saving my money for Smart Racing bars.

All the bolts I used were from Weltmeister. I also switched to SmartRacing, since their hardware much more durable.

jaydubya · 05-02-2005, 06:55 AM

Quote:

Originally posted by john_cramer
It's the toe eccentric, goes in the forward hole on the spring plate.

That explains why I don't remember touching it. Here are pics of the Charlie Bars rear mount.

Edit - looks like my bar has backed out a bit! Better get on that.

HarryD · 05-02-2005, 04:49 PM

Quote:

Originally posted by jaydubya
That explains why I don't remember touching it. Here are pics of the Charlie Bars rear mount.

Edit - looks like my bar has backed out a bit! Better get on that.

That is the factory mount location. For cars like mine that did not come with a rear bar, that mount needs to be added. I assume you can weld one in?

HarryD · 05-02-2005, 04:51 PM

The Weltmeister install looks like this:

jaydubya · 05-02-2005, 05:06 PM

Quote:

Originally posted by HarryD
That is the factory mount location. For cars like mine that did not come with a rear bar, that mount needs to be added. I assume you can weld one in?

Probably not worth the trouble. Also, on my car i think the arm is aluminum which would further complicate the welding.