Remove/replace garage door bottom roller?

Hi all.
I want to remove. for cleaning or replacing, the bottom roller on my garage door. There is no problem with removing the brackets on the other rollers, but on a torsion-spring door the bracket for the bottom roller is hooked to that cable with a grillion pounds of tension in it.
Does anybody know what the trick is?
TIA

wrote:
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When the door is up the tension should be released. My cables hang slack when the door is up

On Tue, 09 Aug 2005 12:22:09 -0400, snipped-for-privacy@aol.com wrote in alt.home.repair:
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Hmmm. I'll have to meditate on that for a while. My cables are still under some tension in the full-up position. They're very short at that time, so it's difficult to guesstimate how heavy the tension is.
I just recalled - a while back I loosened the lock bolts on one of the pulleys to even out the door. I bet I can do that (on one side at a time!) to replace those rollers. I'll have to ponder that.
Thanks for the reply.

On Tue, 09 Aug 2005 17:33:08 GMT, Dick Yuknavech
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Lift the door further than the regular open position. Jam a 2x4 under it to keep it up.

snipped-for-privacy@aol.com wrote:
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Sounds like you're talking about extension springs and he's got torsion springs. Fooling with the tension on torsion springs is considered dangerous by most people, and not a weekend handyman job.
Ken

Here's the difference http://www.clopaydoor.com/spring.asp
One's above the door opening, and the other runs along the sides of the open door.
Ken