[fdm2000]

I have a Craftsman 1/2 hp garage door opener and just had the cables replaced and the door worked perfectly. Today I have a problem;

The door closes to the correct position but immediately reverses and the trolley rides all the way to the stop bolt and hits it with extreme force.

I have decreased the down travel (turned the down screw clockwise) to correct a door that reverses upon closing as the manual suggests and no matter how much I turn the down adjustment screw it seems to have no effect. Could this be a defective adjustment component? Would this also explain why the trolley is riding so far that it slams into the stop bolt

There is nothing binding or interfering with the door or sensor. And the sensors are aligned

Any suggestions would be appreciated.


Frank

[wowzer]

Are the two trip switchs still in place on the trolley?

The sensor are there only to reverse the door when coming down if the beam is interupted.

[fdm2000]

Thanks for the response, wowzer. I removed the motor cover and discovered that the gray wire to the center limit contact was somehow cut in half. I have no clue how this could have happened, I restored the connection and adjusted the up and down screws and hopefully it will continue to function - otherwise I may have to purchase a new limit switch assembly.

The nylon gears appear to be in good working condition and undamaged so I will just buy some lithium grease and lub them.

Frank

[wowzer]

Hopefully that will solve your problem...