Automatic Garage Door Opening/Closing Problems

[GG.and.UN.]

My wife closed one of our garage doors on our child's toy.

If I unhook the garage door from the chain and close it half way the garage door stays in that position so the springs are good. If I re- hook the garage door while in this position and try to close/open the door with the motor it does so just fine until it either closes or opens all the way; at this point the motor starts grinding and rattling loudly and won't stop until I push door button.

If I start with the garage door hooked in the fully open position the motor will start the noise and the garage door won't move.

If I start the garage door hooked in the fully closed position the garage door will open just fine until it hits the fully open position in which the motor starts making the noise.

I unhooked the the garage door and left it fully closed and then tested the movement of the chain without the garage door attached and it moved fully from end to end without any problems.

I hope I exhausted all possibilities and gave enough information to garner some insight.

[RBM]

It sounds like the limit switches need to be readjusted. At the moment the door reaches bottom or top, a limit switch should stop the motor

[Joseph Meehan]

Or replaced. In any case that seems to be the problem. Take a good look at the wires to make sure they are intact.

[buffalobill]

buffalo ny: mine lasted thru the 2 kids growing up. then it was doing that so i screwed around and adjusted and complained about it and ordered a part and installed it and complained more about it. i even had a real garage door opener guy for a tenant, and he have it his best. between the 2 of us we wasted more time on the old unit, should have just bought the replacement unit for him to install at first. has modern safety sensors, outdoor keypad, quiet quiet quiet compaired to old chain drive. i predict that the child's father's toy will be his new quiet rubber belt driven garage door opener professionally installed by [home depot/ lowe's] with extra matching remotes purchased at the same time. and his mom will immediately agree to this safety item for your home.

[trader4]

I don't think there are limit switches in any current vintage garage door openers. They measure movement by counting pulses from the gear drive.

[trader4]

Also meant to say, it doesn't sound like an adjustment issue either. If the limits are out of whack, the unit should still stop after going a bit farther than it should. You would also think the force sensing system would stop the door He says the motor won't stop in either direction unless he hits the switch. I guess he can try backing the limit adjustment to min in each direction an see what happens.

[GG.and.UN.]

Hey everyone, I fixed it.

I took apart the motor housing and noticed that the spur gear was not lined up properly with the worm gear (the spur gear was at about a -45 degree tilt from the horizontal plane. I put everything back in place and everything works great.

Thanks for all the replies!

[Joseph Meehan]

I just checked the Genie site and they still show limit switches on their description of how they work.

[trader4]

Interesting. I wonder why they still use them. I've had several Craftsman over the years as well as a 20 year old LiftMaster. Neither brand used actual switches on the tracks to set the limits. I think they track movement by counting pulses from the gear train, which sounds like a simple design, less wires to run, switches to go bad, etc.

[Joseph Meehan]

I would guess because they work?? It would be interesting to know what the various failure rates are but the switches are relatively simple devices and do seem to work well and reliably. Pulse counting could certainly work, but I see some potential problems with it.

[Bob M.]

There sure are down and up limit switches on my 2005 Genie screw drive.

[doordoc]

The Liftmaster/Chamberlain/Craftsman still use limit switches & always have. The limit switches are under the motor cover & not on the track.

There are/were some units that counted motor revolutions but they were a real pain & had to be reset (re-learned) every time the power went out.

Doordoc www.Acti> >