Lotus Elan

Plus 2 window mechansim spring

PostPost by: lotuselan2 » Sun Sep 15, 2013 7:07 pm

To remove the motor and levers, I unbolted the motor from the lever arm and most know what came next! The spring popped off the lever and only caused a small cut on my hand.

My question is how much does the spring have to be "pre-loaded" before installing on the lever? I know the function of the spring is to adjust for the weight of the window so that it will go up and down at about the same speed (slow and a bit slower but that is another story well posted on this forum). I can easily pre-load the spring a half turn by manipulating the lever and using a vice-grip. Is that enough? How would you turn it more before fitting?
Ken
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PostPost by: DavidLB » Mon Sep 16, 2013 7:27 am

Workshop manual shows a pair of holes that when lined up on the operating levers to hold the spring in tension 1/4 bolt I think will do the job
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PostPost by: stugilmour » Tue Sep 17, 2013 5:43 pm

DavidLB wrote:Workshop manual shows a pair of holes that when lined up on the operating levers to hold the spring in tension 1/4 bolt I think will do the job



That's how I did it, but can't recall details. Might have shoved a screw driver in the holes. Window taped in the up position. Have a magnet wand ready to fish the fasteners out of the door when dropped. :)
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PostPost by: lotuselan2 » Fri Sep 20, 2013 12:03 am

Will check shop manual, DUH!
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PostPost by: bob_rich » Sun Sep 29, 2013 10:46 am

Hi Ken

Been there did that as well!
with the plate off the motor I recall I held the blade in a vice then rotated the plate until the spring looked like the other motor's spring and then used a bolt to hold the plate to blade in tension while I reassembled onto the motor

Have attached a picture of the spring on my other motor as its out of the car at present

Hope this helps best of luck

Bob
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window_lift_motor_spring.JPG and
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PostPost by: lotuselan2 » Sun Sep 29, 2013 11:03 pm

Bob
If I get this right, you do not need to add an extra rotation to the spring which would be a real task. I put plate in the position that would give the least tension and then forced the spring on with a screw driver. All changes in plate position would be higher tension. I think I got it! Next weekend will tell.
Ken
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PostPost by: bob_rich » Mon Sep 30, 2013 5:27 pm

Hi ken

I am going from memory but I think it is about 1.5 turns. I put the blade in a vice held near the far end so the plate that holds the motor could rotate through a full 360 degrees ( Motor was off 4 this) The spring is put on so that it is unwinds on lift and tightens on lower. I put the spring on with the plate over the blade and then turned the plate a bit over 1 turn until I cold drop a bolt through from the motor side to lock it in position. then fitted the motor and then the holding bolts could be removed. I used garden gloves and turning the plate through a full turn and a bit was had but not unreasonable.

I have another thread on a related subject as I am reassembling my passengers door at present

Hope this helps best of luck

Bob
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PostPost by: LotusEngineeringBuff » Mon Mar 18, 2024 5:08 pm

bob_rich wrote:Hi ken

I am going from memory but I think it is about 1.5 turns [... I used garden gloves and turning the plate through a full turn and a bit was had but not unreasonable. [...]

Bob


Well. I beg to disagree. I managed to turn the spiral spring about a half-turn +45 degrees from idle until the arm lined up with the motor support bracket. Then I tried to add another 1/2 turn to see if I could add more pre-load but no. The spiral spring was so tightly coiled over itself that it blocked before the half turn was reached. (You can try in 1/2-turn increments because there are 2 positions at 180 degrees where you can locate the spring)

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