Torsion Bar

[penciltester]

Sweet Jesus! Nothing like having your driver side torsion bar snap while driving down the road to scare the ever loving crap out of you.

So now I get to replace the torsion bar. I have seen the replacement part from DMC but I have also seen the Blue Sky torsion spring. Have any of you purchased the Blue sky product or heard anything about them? What about their strut bracket, worth it? Your opinions are always invaluable.


Thanks again guys.

[DavidProehl]

I've never seen one of the spring bars used, but I've also never heard of them failing so I'm assuming they must either be ok or no one has been using them.

The other option is a DMOCO bar: http://www.dmoco.com/Torsion.html

I had my driver side bar break when driving as well. I thought my engine had blown up until I realized it was still running. Still made me pull over and shut the car off immediately while in a panic.

[mluder]

I recently replaced mine with a used bar from DPI... Your DMC affiliate of choice may or may not have access to used originals too. Give them a call.

Cheers
Steven

[john 05141]

snapping while driving? I did not realize that is possible.
Iguess your skull is safe under that 5mm think fibreglass.

Jan

[penciltester]

Thanks for the info guys. Well if no one on here has a torsion spring spring from Blue Sky I might as well be the guinea pig.

[Dangermouse]

Is "Blue Sky" aka Henninger? I have never heard them called that before

Here is his unit (videoed on a 10x10 pixel camera apparently- ;) )


https://www.youtube.com/watch?v=-73qKHHtSCM

[penciltester]

Yes, they are the same. I read something about their strut/torsion door system being called blue sky. I may be mistaken, sorry for the confusion. Thanks for clearing that up.

[Andrew]

I installed one of Byrne Henninger's door torsion springs on 4194 last year. I can personally attest to the fact that it is a high-quality product which functions well. Installation and setting the torsion was simple and straightforward.

By the way, the torsion spring seems to have the same physics concept as a rotary garage door spring.

[opethmike]

snapping while driving? I did not realize that is possible.
Iguess your skull is safe under that 5mm think fibreglass.

Jan

That is when they are most likely to snap; closed door = max tension.

[JRNY13]

That is when they are most likely to snap; closed door = max tension.


How common is this? It's a scary thought.

[mluder]

How common is this? It's a scary thought.

Not common at all... The torsion bard were tested to over a million cycles or some wild number like that. I just happened to be lucky.
There are a few precautions you can take. Visually inspect your bars regularly for nicks or scratches - That's typically why they fail.
Make sure the rear door hinge is not rubbing on the bar - this is a common source for the above mentioned scratches/nicks. You should be able to fit a playing card or similar between.
There's also a procedure for cleaning off surface rust. I don't know it off the top of my head so I won't even try to guess. It's here on the forum somewhere. Perhaps some one with a better memory can point you to it if a search doesn't turn it up.

All that said, your mileage may very and you could do all of this and it will still snap tomorrow. Like I said it's rare but does happen.

Cheers
Steven

[Rich]

There are a few precautions you can take. Visually inspect your bars regularly for nicks or scratches - That's typically why they fail.
Make sure the rear door hinge is not rubbing on the bar - this is a common source for the above mentioned scratches/nicks. You should be able to fit a playing card or similar between.


+1 on this.

In case an inspection turns up a torsion bar touching the rear hinge a simple remedy is to slip a short length of strong hose or tubing over the bar to cushion it against the hinge. Slit is lengthwise to get it over the bar and orient the slit anywhere but facing the hinge. The bar may bend a bit with the hose there but that won't cause a problem.

Manufacturing variations mean that some bars hit the hinge and some don't. Don't take chances, just prevent any nicks.

PS, the OP on this thread could perhaps tell us at which location their particular torsion bar failed - if not reported already here. Anywhere near the rear hinge?

[Dangermouse]

All the ones I've seen are at the rear of the bar, presumably where the stresses are greatest near the fixed part of the bar.

Just personal theory on this, but I think in the cases where the roof box is starting to separate, that allows the bar to come in contact with the rear hinge and gets a little nick in the bar which acts as a stress crack. I don't think minor surface rust will affect the integrity of the bar, but it may hide a nick.

[papanoel]

+1 on this.

In case an inspection turns up a torsion bar touching the rear hinge a simple remedy is to slip a short length of strong hose or tubing over the bar to cushion it against the hinge. Slit is lengthwise to get it over the bar and orient the slit anywhere but facing the hinge. The bar may bend a bit with the hose there but that won't cause a problem.

Manufacturing variations mean that some bars hit the hinge and some don't. Don't take chances, just prevent any nicks.

PS, the OP on this thread could perhaps tell us at which location their particular torsion bar failed - if not reported already here. Anywhere near the rear hinge?

my car has a zip tie in that spot to prevent rubbing.

[David T]

my car has a zip tie in that spot to prevent rubbing.

All the ones I have ever seen break where they pass by the rear hinge. My guess is that they rub it and get scratched creating a stress riser where it finally breaks. I just take a piece of rubber from an old inner tube about 1" by 2" and pull the bar away and stick it in between the bar and the hinge.

[opethmike]

Kind of like has already been mentioned several times, eh Guru?

[Patrick C]

Cinching a plastic zip tie around the bar where is nears the rear hinge is the best preventative fix for the bar rubbing the hinge. It works well and looks better than an old piece of rubber scrap.

[mluder]

Interestingly (or maybe not) mine broke near the front of the car. Hard to tell if there was a nick or not as when it breaks it essentially shatters and pieces chip off.

It's the most sickening sound. I had arrived at the gym. Parked, closed the door and as I was walking away heard a loud pop. I knew right away what it was. Got back in to the car and immediately went home. Exercise motivation deleted.

Cheers
Steven

[Delorean3610]

Interestingly (or maybe not) mine broke near the front of the car. Hard to tell if there was a nick or not as when it breaks it essentially shatters and pieces chip off.

It's the most sickening sound. I had arrived at the gym. Parked, closed the door and as I was walking away heard a loud pop. I knew right away what it was. Got back in to the car and immediately went home. Exercise motivation deleted.

Cheers
Steven

You could have done a few sets of door lifts at home anyway.

[Rich]

All the ones I've seen are at the rear of the bar, presumably where the stresses are greatest near the fixed part of the bar.

Just personal theory on this, but I think in the cases where the roof box is starting to separate, that allows the bar to come in contact with the rear hinge and gets a little nick in the bar which acts as a stress crack. I don't think minor surface rust will affect the integrity of the bar, but it may hide a nick.

It turns out the stresses along a circular bar of constant diameter are equal from one end to the other, assuming the torsion loads are only at the ends, as in this application.

Yes, a nick or scratch that's deep enough can create the stress concentration that can eventually lead to a failure at or near the point of the defect.

[penciltester]

Thanks everybody for chiming in. The bar broke off center near the rear hinge. Some have mentioned roof box separation being a probable cause for added stress on the bar. Has anyone reattached their roof box themselves? Or is this a road trip to DMC Midwest kinda thing?

Thanks again everyone.

[opethmike]

Reattachment is perfectly do-able DIY. If you want to replace the roof box, that's an entirely different matter.

[Andrew]

Reattachment is perfectly do-able DIY. If you want to replace the roof box, that's an entirely different matter.

+1 4194's torsion bar failure was the result of roof box separation. The reattachment was not too difficult of a job, but did entail removal of the t-panel and interior headliner. I decided to err on the side of additional precaution and strength; thus, I ended up using a total of 8 5/16 lag bolts combined with fender washers which I placed in a 4 bolt square pattern approximately 2 inches from each torsion bar. Obviously stay far away from the torsion bar passage when drilling any holes. After securely tightening the nuts, I carefully used a die grinder to trim excess from the bolts. BTW I used a towel to shield the rear window from any flying debris while using the die grinder. Upon the reinstallation of the headliner and the t-panel, the repair is 100% undetectable.

I posted the pictures on Today under the topic "4194's Torsion Bar"

Best of luck!

Andrew
4194
5052

[opethmike]

+1 4194's torsion bar failure was the result of roof box separation. The reattachment was not too difficult of a job, but did entail removal of the t-panel and interior headliner. I decided to err on the side of additional precaution and strength; thus, I ended up using a total of 8 5/16 lag bolts combined with fender washers which I placed in a 4 bolt square pattern approximately 2 inches from each torsion bar. Obviously stay far away from the torsion bar passage when drilling any holes. After securely tightening the nuts, I carefully used a die grinder to trim excess from the bolts. BTW I used a towel to shield the rear window from any flying debris while using the die grinder. Upon the reinstallation of the headliner and the t-panel, the repair is 100% undetectable.

I posted the pictures on Today under the topic "4194's Torsion Bar"

Best of luck!

Andrew
4194
5052


That is the EXACT same repair I did on my car. It's a rock solid fix, that I think every DMC owner should consider.

[PJ Grady Inc.]

It turns out the stresses along a circular bar of constant diameter are equal from one end to the other, assuming the torsion loads are only at the ends, as in this application.

Yes, a nick or scratch that's deep enough can create the stress concentration that can eventually lead to a failure at or near the point of the defect.

If you're speaking hypothetically about this, based on a text or your education, I can agree based on my personal experience. Over the years I've seen, heard, or otherwise replaced a couple dozen bars that have broken suddenly. They usually come in to our shop broken but I've had a couple break while sitting in our shop and one break on a road test 25 to 30 years ago. If are you in the car when it happens I can tell you it sounds like a large caliber rifle firing inch's from your head and is alarming to say the least! Fortunately this is extremely rare as it only happened to me once in 35 years while road testing over a thousand Delorean's and many personal/business road trips in my own cars. It's not likely to ever happen to you!

In a side note when an original coolant tank blows apart at its seams under pressure, which has also happened once while road testing, it sounds about like a 22 cal. round going off behind you. It's comparative piece of cake on the alarm scale!

Delorean's, like their creator, tend to make large theatrical noises even in failure mode! Most of the T bar failures are caused by rubbing on the rear hinges but I've seen failures towards the middle and front hinge areas as well. Sometimes it starts as a tiny hairline fissure that shows signs of previous rust once the breakage occur's. Usually but not always it starts where the surface was rubbed, scratched, or otherwise breached which compromises the bar's integrity under load. On all failures I can recall there is always some preexisting rusted crack of varying depth that precipitates the outright failure of the bar. I have never heard of a failure when the door was open. I have some broken bars laying around and if I get the time and can take a clean pic I may try to post one or two of the more interesting "breaks".
Rob

[Rich_NYS]

Cinching a plastic zip tie around the bar where is nears the rear hinge is the best preventative fix for the bar rubbing the hinge. It works well and looks better than an old piece of rubber scrap.

Pat, would you post a pic please? It sounds really simple, but I'd like to see it before I do it so I know I totally have it right.

Thanks!

[Patrick C]

Pat, would you post a pic please? It sounds really simple, but I'd like to see it before I do it so I know I totally have it right.

Thanks!

My car is in storage, but basically open the door, get the zip tie, gently pull the torsion bar away towards you and away from the hinge (it will move), wrap the zip tie around the bar and cinch it, and release the bar. The snug zip tie will now be a protective "layer" around the bar, so to speak, and will prevent the metal bar from ever touching the metal hinge.

[Rich_NYS]

My car is in storage, but basically open the door, get the zip tie, gently pull the torsion bar away towards you and away from the hinge (it will move), wrap the zip tie around the bar and cinch it, and release the bar. The snug zip tie will now be a protective "layer" around the bar, so to speak, and will prevent the metal bar from ever touching the metal hinge.

Thanks Pat, I have a lot of different width zip ties...maybe even one that's close to 3/4". Did you use the widest one you could find?

[PJ Grady Inc.]

My car is in storage, but basically open the door, get the zip tie, gently pull the torsion bar away towards you and away from the hinge (it will move), wrap the zip tie around the bar and cinch it, and release the bar. The snug zip tie will now be a protective "layer" around the bar, so to speak, and will prevent the metal bar from ever touching the metal hinge.

My favorite method of insulating the bar against the rear hinge is to do it with the bar removed and installing a 3/4" piece of 3M heat-shrink tubing or the equivalent. Looks very subtle and rather neat in appearance but requires removal and therefore a bit of expertise to execute but it's de rigour if the bar happens to be out for roof servicing.
Rob

[Ryan S.]

Roof box repair photos.
http://www.deloreanreborn.com/index.php?itemid=96
A couple of years ago, Clint fixed mine.

[pk2678]

How about that:


http://www.ebay.com/itm/222015037005

[mluder]

You could have done a few sets of door lifts at home anyway.

:strongman:

[mluder]

How about that:


http://www.ebay.com/itm/222015037005

That's a pretty good price... Of course you gambling on the condition.
I bought mine from Josh at DPI and he gave me a fair price, assurance the bar was inspected, and a warranty.

Cheers
Steven

[DavidProehl]

How about that:


http://www.ebay.com/itm/222015037005

Right side bar. That would be passenger side. The OP needs a left side bar.

[pk2678]

Right side bar. That would be passenger side. The OP needs a left side bar.

Sorry for the misinformation. I should have read the first post more carefully.

[Lwanmtr]

I've heard of these snapping, so since mines not running and sitting in garage i just have my doors open...plus it helps save the struts a little.

On a side note...I wonder if the sound you guys describe is comparable to a rear wheel coming loose and the car dropping down onto the rim while driving...lol

[dn010]

I wouldn't gamble on that bar, if you look at the 11" mark you can see the bar has been scratched/scored.


How about that:


http://www.ebay.com/itm/222015037005

[SS Spoiler]

Possible to polish the bars to a mirror finish? Would that help?

[dn010]

I try to leave the bars alone as much as possible, from what I understand any nick or ding on it weakens it and increases the chances of breaking.


Possible to polish the bars to a mirror finish? Would that help?

[PJ Grady Inc.]

I try to leave the bars alone as much as possible, from what I understand any nick or ding on it weakens it and increases the chances of breaking.

Agreed...apart from being the wrong side it looks too rough to take a chance on anyway.
Rob

[penciltester]

Thanks again everyone for the replies and the help. Also, sorry for the late reply. My life kinda went sideways for a bit. I'm thinking about getting the torsion spring, http://deloreannewparts.com/store/page11.html . Partly for price and partly for curiosity. And yes I know what curiosity did to the cat. :)

[81dmc]

Thanks again everyone for the replies and the help. Also, sorry for the late reply. My life kinda went sideways for a bit. I'm thinking about getting the torsion spring, http://deloreannewparts.com/store/page11.html . Partly for price and partly for curiosity. And yes I know what curiosity did to the cat. :)

If the finish ever begins to crack, you can repaint it with a flexible aircraft paint.

[content22207_2]

Byrne's torsion unit uses the same principle as the big spring that holds your garage door up. I'm pretty sure one day he looked up in his garage and said "hey, that'll work".

I bought a set for #5939 but haven't gotten around to installing them yet. I'm pretty sure Steve Rice installed his if anyone wants to see them in action at DCS'16.

Bill Robertson
#5939

[AugustneverEnds]

I know it's not good etiquette to resurrect dormant threads but I was wondering what happened with the OP's situation. I presently find myself in a similar place.

[Maritime-elf]

I had to have my passenger side torsion bar replaced about a year ago....Jesus was it expensive. The best price I found was at Delorean Auto Parts(Special T Auto) I have never seen the springs in action. I tried to find them when my Torsion bar broke but I couldn't find them for sale anywhere.

[Dangermouse]

FWIW, Byrne retired and the spring type are therefore no longer being manufactured

[Maritime-elf]

Although I try to keep my Delorean as original as possible. It would be awesome if someone was able to get in touch with him, and get the plans/schematics. As torsion bars run out, it might be the future cost effective solution.

[Andrew]

FWIW, Byrne retired and the spring type are therefore no longer being manufactured

I'm running one of Byrne's units on 4194. I've been really happy with it.

Has anyone contacted Byrne to inquire as to whether he would be willing to sell the design of the torsion spring unit?

Andrew
4194
5052

[DMCMW Dave]

I'm running one of Byrne's units on 4194. I've been really happy with it.

Has anyone contacted Byrne to inquire as to whether he would be willing to sell the design of the torsion spring unit?

Andrew
4194
5052

Byrne is no longer in business nor available. Not sure what happened with his products other than being sold off.

http://dmctalk.org/showthread.php?15201-Byrne-Heninger-deloreanupgradeparts-com-officially-closed-retired

Website is gone.

[Lwanmtr]

Its too bad someone couldnt have gotten the designs for the torsion bars before he disapeared...though clever folks could prolly reverse engineer it.

[Rich_NYS]

When I saw the Byrne torsion on his website I thought it was unattractive, but when I saw it installed on Andrew's car I was pretty impressed at how good it looks...I'd totally put them on my car.

I was going to get a few to put on the shelf, but then things changed with Byrne.

I think Bill was pretty close to him, he might be the best source of intel in regards to remaining stock and/or design plans.