Genie screw drive garage door opener - gap in the screw

[Mother Fussbudget]

I moved into a house in December, and soon repaired the old Genie garage door opener so that it worked.  But after a month of use, the 'runner' that slides down the track driven by the 'screw drive', now hesitates at a point 18" from the top of the run, and 'grinds'. 

After some investigation, I notice that the point at which the sled/runner stops and grinds is exactly where there's a gap in the screw teeth.

Q:  has anyone run into something like this?  Is there something I can do to adjust / repair the gap in the screw drive?

[zolotiyeruki]

Can you post a picture?  This sounds interesting.

[DragonSlayer]

We had this exact problem (if I'm understanding your problem correctly). The carriage that rides up and down the screw had lost a few teeth. Problem solved by a $15 part, like this:

http://www.amazon.com/Genie-20414R-Carriage-Screw-Operators/dp/B000JFFEFW/ref=sr_1_45?ie=UTF8&qid=1424881103&sr=8-45&keywords=garage+door+opener

You'll need to research your exact model of opener, as there are several different kinds of these.

(Although, now that I reread your post, it might not be the carriage, but the screw itself that's somehow stripped? If that's the case, I don't know what to do other than see if you can get a replacement screw, although I'd still check the carriage to make sure it's not missing teeth. No sense taking the thing apart twice.)

[Mother Fussbudget]

Thanks for the tip - I'll take the carriage apart this weekend, have a look at the teeth, and report back.
And I *will* post a picture at first opportunity. 
Yes, there is a 1-inch 'gap' in the screw itself where the screw spirals are missing.  I'm not sure if this is normal or not.  Someone I work with said 'that's normal, and that the carriage would normally span across this gap without problem'.

FYI... the gap on the screw is approximately 14-inches from the 'limit switch' (the one closest to the motor) on my door drive mechanism. 

[Tyler]

The lead screw is usually not a single continuous rod (which would be too large to package and ship).  My Genie is broken into three segments, and the joints have a gap with no thread.  That's normal. 

The carriage seems like a good place to start.  I'd also make sure that everything (screw, carriage, door rollers, spring, etc) is properly lubricated, as friction can cause problems.  It's very easy -- just make sure you use lithium grease and NOT WD-40. 

[Mother Fussbudget]

Solved!

Yes, the 'gaps' (there are 2 on my screw) are designed into the mechanism.  I found an on-line installation guide that showed they were correct.  So I tightened a couple of loose track brackets... and replaced the carriage. 

The carriage replacement did the trick - the first two (2x) teeth in the old one looked like a crack addict's canines. 
Now the entire door moves more smoothly, and all is good.  New carriage, and new remote control <$50

Thanks everyone for the suggestions!