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Old 11-02-2008, 01:02 PM
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"Basics of Basics" Sprung door repair.

"Basics of Basics" Sprung door.
By Brian Martin

This is one of those tricks that after you see it in action, you just can't believe you can get such a huge result from such a little action.

First off, what is "Sprung"? This is when the door is opened beyond it's normal operation bending the hinges and or mounting. It usually results in the door being too far forward. It will also put the door up or down in the back depending on if one of the hinges was effect more when the door was pushed too far open ("sprung").

So after this happens you can have a door that is hitting the front fender (or the front door in the case of the rear door in a four door being sprung) or it can be much less with the door being simply a little further forward or up or down in the back if it wasn't sprung that hard. It can happen when the door is opened as the car comes to a stop, or someone simply pushes on the door opening it further than it is designed to open. Or in extreme cases it is bent badly being sprung by driving the car backwards with the door open and the door hits a post, garage wall, fence or another car.

I have seen doors that were bent so bad you couldn't even think of closing them, with the door WAY forward or WAY high or low in the rear being fixed with this little trick. I have also seen them where they are folded over the front fender with the hinges ripped in two so it isn't going to work every time.

Here is goes, look at "Fig # 1" and you will see where the door has opened "E" and the stop built into the hinge ("1") and did it's job stopping hinge from swinging too far. One problem, the door bent at "B" and "D" and the hinge/cowl pillar bent at "A" and "C". At "A" it bent into the hinge/cowl and at "B" it bent into the door. And at "C" and "D" it bent pulling the metal away from the hinge/cowl and away from the door.


In "Fig # 2" you can see how if you put something into the hinge to block the movement of the hinge from closing at #2 and pull the door onto it, applying pressure "E", you are going to bend the door IN at "B", IN at "A", and OUT at "C" and OUT at "D", exactly opposite what happened when the hinge was held from opening too far. Is that cool or what? Remember the hinge is VERY strong and you are not going to damage it by doing this, at least not before the metal on the door and cowl bend first.


This can be done with something like a socket as in photo #1 on this Ford Windstar. There is very little room so something like this works well.


Or it can be done with a piece of wood or what ever else you can find if you have a little more room like on this 65 GM A body, Photo #2. In this case, the wood still is a little big and if I were to close the door on it, the 2x4 would be resting on the cowl it's self right next to the hinge. This would likely cause some damage at that point on the cowl being the forces created by all that leverage would be localized right there. But sometimes this works to your advantage because the cowl IS pushed out right there. But most of the time you are going to want the item you put there to be touching nothing but the hinge so it is focusing the forces on exactly the same points the hinge did when the door was sprung.


You would be surprised how often you can make minor adjustments on door fit when the door hasn't even been sprung. If you are fitting a door and it is at the end of the adjustment holes on the hinge and won't go back any further, a little "tweek" like this can do the trick.

Now, is this "hack" work or something, not on your life. It is no different than "massaging" metal in any other way to get it to do what you want it to do. And how do you like this, this exact method is used at the factory every day! Yep, right on the line over at the NUMMI plant where they build Toyotas and Pontiac Vibes in Fremont California there are people doing this very thing as the car is on it's last few stations before it rolls out of the plant. I have to assume it happens at many other assembly plants.

Of course, if your car uses a "Check strap" of some kind to limit door travel then that check strap is likely damaged. Some cars have this limit built into the hinge as the two I have provided photos of. But many cars don't have this limit built into the hinge, or at least it not designed to limit the travel as well and the door would hit the fender before the hinge stopped it. The check strap is usually on lighter cars where the hinges are made lighter. These were first found on early cars in the form of a strap of leather or something screwed to the door and to the hinge/cowl panel, hints the name "Check STRAP". Of course these days it is in the form of a metal or plastic piece that sticks out of the front of the door and bolts to a pivot on the hinge/cowl pillar right in the middle between the hinges. Many times a door will be "sprung" and this strap will get damaged inside the door. So you want to be sure to check to see if the strap is still working properly restricting the movement of the door. If not, it needs to be replaced.

And to figure out which hinge to do if the door is up or down, this "Basics" on panel alignment will spell it all out. http://autobodystore.com/ms1.shtml

Last edited by MARTINSR; 11-02-2008 at 03:59 PM. Reason: Forgot some good info.
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