Help with adjusting Torsion bars

[flux3d]

Right, well after trying to adjust the door on 10719 I've come to the conclusion that the torsion bar, for whatever reason, has been slackened off. After reading around I gather that without the strut in place the torsion bar should lift the door the first few inches. Mine does no such thing, in fact the door pretty much stays put when you open it. This explains why even after putting on new struts I have to push the drivers side up the last few inches.

Question is, how is it done? I know its a pretty hair-raising job to do, and can cause no end of damage if done incorrectly. Can anyone give any pointers, or even better help me out with doing it. I'm happy to drive to you if you can spare the time.

[Rich H]

PM Sent...

[Rissy]

Having to push the door that last inch or two at the top end of opening is not down to the torsion bar not being torqued up correctly. The strut both keeps the momentum of the bar going, and also slows down the door that last inch or two to the fully open position, and this varies quite a lot according to ambient temperature. My doors for instance, come up really quite fast in the summer, and if left to hit the top themselves, then they will do the normal thing of a bit of a bump and wobble. However, in the winter, the door wont make it to the top at all without a helping nudge that last couple of inches due to the colder ambient temperature.

You ARE right in saying that with all the sources i've checked out on the net, without a strut, the bar should just move the door out from the closed position by a few inches itself and then stop. This is because the bar itself is only meant for kicking off the movement, and it's the strut which keeps the momentum going after that, helping the bar to straighten out its applied torque.

From a rested position, with the door open to the top and held in place with something to stop it falling back down, when the torsion bar is inserted, it only needs to be turned towards the outside of the car, by about 1/8 of a turn i.e. 45 degress. and then fastened in place with the brace. This CAN vary slightly between bars, but not by much. The brace and the bar is splined, and normally if not torqued enough, or by too much, but close to where it should be, then normally only one more tooth on the spline in the appropriate direction, is enough to correct the torque. It really does need that little adjustment.

However, adjusting the torsion bar should be the last thing you should have to do if it's been done fine in the first place. The first checks i'd make is the strut for one, but your case, you're querying the initial kick from the bar. So, the next thing is, are you sure the door is not sticking on a latch or both latches first of all? Are you closing the door to the point before where it can get stuck on the door seals or the latches? This would be enough to hold back the initial kick from the bar.

I've never adjusted one, so i might be WAAAY off, but i HAVE read a lot about it, looked at quite a few pictures and watched a few videos over the years.

[Rich H]

I don't know where this ridiculous 'initial kick myth' comes from :roll:
The torsion bar is a counterbalance for the door, plain and simple.
There is no way the strut could lift the door on it's own without it.

The bars need to be tightened clockwise on the drivers side and
anticlockwise on the passenger side.

It's an easy procedure to do once you know what you're doing.
It's also very easy to mess up and cause some serious damage when you don't.
There are a few nightmare problems too which can cause major trouble....

[Rissy]

...This is one of my sources...

http://www.pjgrady.co.uk/GenericContent ... _Bars.html

"The DeLorean gull wings are no different. So, the torsion bar is really simulating a manual lift for the first couple of inches – for the gas strut to take over."

Why is it clockwise for the Driver's side and anti clockwise for the passenger? My understanding was that you're loading the bar by closing the door, and the bar is trying to straighten out by opening the door again, but you don't want it to fully unwind by the time it hits the top, therefore you need to still have some load on it at the open position, therefore still with a bit of twist in the bar towards the closing action....? I'm trying to put my mechanics head on and visualise it, and my head keeps telling me that you want to load the bar in the opposite direction from what you're saying? (I'm sure I'm wrong. You're an expert, but i'd just like it explaining to me. In my head, doing it your way would result in the bar straightening out fully before it hits the top, and then try to twist the other way again?)

[Rissy]

Found a video source. You're right, but I still can't get my head around it!??

https://www.youtube.com/watch?v=nUdxbG3qA3g

[Rissy]

...Another source...

"Before removing the torsion bar, it's worth a moment to check to see if any adjustments will be needed when it goes back in. Without the strut installed, the door should hang open by 1-2 inches."

http://www.noroads.com/delorean/3281/?content=20091107

[Dangermouse]

As someone who drove his car for 6 months without a drivers side T-bar, I can absolutely guarantee that the T-bar does all the heavy lifting from Closed to Open. There is nothing quite like opening the door from the drivers seat and getting out, while holding the door above your head (even with a strut attached)

The strut is just a mini-shock absorber that takes the "bounce" out of the end of travel, and holds the door in place.

The bars were twisted in opposite directions during manufacture, depending on which door they are for. They are keyed to prevent installation in the wrong side.

Note that in the video, the rear panels are taken off. Makes the job easier, but not really necessary. It's straightforward to do, but a helper is very beneficial. Better yet is if that helper has done this before.

[Rissy]

Ha-Ha! It's just clicked why I had it the wrong way in my head. I forgot it's the rear which is fixed and the front which twists, so this correct torquing would put the load on the bar which I was expecting, on the front of the bar! sorry for the confusion, but trust me when I say you weren't half as confused as me! ha-ha!

Anyway, what about the two sources of the 1-2 inches of necessary "initial kick"/"initial simulated lift" from the bar before the strut takes over the travel momentum and then deceleration at the end of travel?

I'm not saying the torsion bar isn't required for lifting the door, of course it is, but i'm saying that without the strut, then you'd have to assist the torsion bar in opening the door all the way to the top, and then slow it down at the top as the weight of the door moves perpendicular to the roof before it runs away with you. (if you get me)

[Rissy]

I'll tell you what would be nice. If Rich H is going to hep you out with a torsion bar adjustment (since we don't know what was PM'd), is if you could video the whole thing, and maybe take photos at each stage. Good for people to watch, and good for the magazine... :wink:

[Rich H]

There's already a video of me doing a drivers side torsion bar at the DOC Norfolk event here:

https://www.youtube.com/watch?v=dXl0t4wffdA

Starts at about 2:00 Unfortunately it doesn't show me checking out the balance of the door to see whether it needed adjusting. It had been fitted with new struts but failed to open fully.

It is indeed right that the door should hang open by a couple of inches without the strut, but that's not an 'initial kick' - it's a good rule of thumb for checking the tension of the bar - the 'proper' way of doing it of course would be to use a torque meter, but that would be overkill.

Quote:Anyway, what about the two sources of the 1-2 inches of necessary "initial kick"/"initial simulated lift" from the bar before the strut takes over the travel momentum and then deceleration at the end of travel?

See my previous post...there is no 'initial kick' or 'simulated lift' if you close the door without the strut, it doesn't pop open. The strut doesn't 'take over' it does all the lifting of the counterbalanced door - without the torsion bar the door would simply be too heavy for it.

If you'd like, I can set your torsion bars so you don't even need the struts - but that's a different story...

[Rissy]

RichH Wrote:The strut doesn't 'take over' it does all the lifting of the counterbalanced door

Ah, right. Gotcha! It's the force in the torqued bar which is equal in force to that of the weight of the door, except, with the door opening, the weight of the door moves from being directly against the opposing force of the torsion bar, to perpendicular to it, meaning less and less resistance the higher up it moves, and this is why the strut also acts as a brake at the top end to dampen the movement of the door at the top end....

...correct?

...and to torque the bar so that there is no need for a strut at all, would in effect be over torquing the bar, and reduce its life.

[Rich H]

Quote:...correct?

Yes! Although the torsion bar doesn't truly counterbalance the door, otherwise it would hover midway between open and shut, needing to be either pushed closed, or pushed open.

Quote:...and to torque the bar so that there is no need for a strut at all, would in effect be over torquing the bar, and reduce its life.

It was designed like that.

See this post I made way back in 2005 on the DOC Yahoo Newsgroup when I met a chap called Roger Cowman at one of the first local shows I went to...

http://www.projectvixen.com/dmcuk-archive/msg15299.html

You can't beat first hand information eh?! :wink:

[Rissy]

...why is it everyone speaks in riddles and half the information in this club.....?

Right, ok, so for the shear entertainment of it all, please explain then, why not torque up the bars to do this then, and either do away with the struts, or just have them there for softening of the door opening procedure then?

[Rich H]

Quote:...why is it everyone speaks in riddles and half the information in this club.....?

I don't! Did you read the page :?:

Quote:....the early "slidey window" cars worked exclusively on the torsion bar, but fears were expressed about what would happen if it broke with your leg half way out!

I'm not sure I can add any more to that...