Garage Door Opener

Question:
I have a Sears screw drive opener, model #953992, 1/2 hp. I had this opener running for quite a while, and then had a bad water leak upstairs...water leaked into the garage ceiling and damaged the opener. I fixed all the water damage and went down and bought the exact same opener, thinking all I had to do was change the motor, and
I wouldn't have to deal with assembling a new rail, door sensors etc.

I put the new motor on as planned and fired it up. All it did was hum briefly and stop, and then gave me 5 blinking lights in the back. I didn't pay any attention to where the trolley was on the rail when I installed it, but (after reading the directions) I learned that it was supposed to be positioned about 9" from the end of the rail, nearest the door. So I moved the trolley, but in the meantime, I turned the heck out of the adjustment screws trying to figure out what was wrong.

So now, the door runs okay, but runs the door all the way down, and right back up til the trolley hits the limit pin near the motor and stops. I try adjusting the limit screws, but it doesn't seem like it's doing anything. My fear is that I messed with them so much that they backed all the way out, or no longer work for some reason.

I'm thinking of calling a pro at this point, but if I could get it back to some kind of reference point to start out, I think I could get it adjusted...right now I have no idea where I'm at.

Any suggestions or should I call a pro?

Answer:
I kind of doubt a pro would be that helpful in this case. Maybe go back to the store and if they have a floor sample, screw the adjustments in all the way, counting the number of turns. I assume they will stop at some point.
If they don't then you might check the installation instructions to see if there is a help number to call. But I would be surprised if they don't stop at some point.

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