Vent window play - '64 convertible

[Jean Cadenhead (40193)]

How much play in a vent window is acceptable for Ops judging?

When my vent windows are say half way open, I have play of betweem 1/2" and 3/4" at the unframed edge of the glass. When moving the glass back and forth, the regulator handle remains stationary. I just replaced the coupe regulators that were in the car with correct convertible regulators. A similar amount of play could be induced with the old regulators even though now that they are out of the car, the old regulators seem tight as can be. Because the rotating shaft of the vent window fits tightly in a slot in the regulator driven shaft, I am at a loss to determine the source of the play.
Thanks,
Charlie

[William Clupper (618)]

Re: Vent window play - '64 convertible

If you disassemble the regulators, I believe an inspection of the internals will show wear on the soft gear that is causing the broblem.

[Jean Cadenhead (40193)]

Re: Vent window play - '64 convertible

Thanks for the reply Bill. I had already rebuilt the incorrect (coupe) regulators and installed new gear sets in each and the play persisted. Now, with new correct (convertible) regulators purchased and installed I continue to have the same problem with play. I do not think it is a gear problem.
Cheers,
Charlie

[Robert Schenkel (42286)]

Re: Vent window play - '64 convertible

I think Bill in on the right track. If you think about it, the play can only be between the two gears, either due to wear or spacing between the two gears.

A less likely option would be the vent frame to gear shaft or if there is play between the gear(s) and shaft(s) they are mounted on.

[William Clupper (618)]

Re: Vent window play - '64 convertible

also look for excessive play in the case where the gear attached to the shaft for the handle is contained. I've used a wave washer behind the gear in some cases.

[Jean Cadenhead (40193)]

Re: Vent window play - '64 convertible

Thanks Bob. I also thought the gear set would be the first place to look but that doesn't seem to be the problem. That is why I was surprised when I first replaced the gears in the regulators and the play was still evident. In the regulators that I rebuilt, with the regulators on the bench there is just about zero play in the gear set when I hold the output shaft and try to turn the input shaft. Perhaps this minute amount of slack translates into a lot of play at the window. Beats me!
Cheers,
Charlie

[Jean Cadenhead (40193)]

Thanks Bill *NM*

[Tracy Crisler (40411)]

Re: Vent window play - '64 convertible

Hope you can get an answer to your question Charlie. Is a quarter turn of handle freeplay OK or is more or less the norm?

tc

[Jack Humphrey (17100)]

The answer is in the book...

How much play is too much for vent window operation? From the NCRS 1963-67 Corvette Operations Manual & PV Guide:

"Vent windows should open and fully close easily and not exhibit excessive wear or play in the regulator assembly. Typically, a regulator within specification will operate the vent window within on quarter turn of the regulator handle...."

[Jean Cadenhead (40193)]

Re: The answer is in the book...

Thanks Jack, but my book sprouted legs and walked off our Chapter's table at our Flight Judging meet in Feb. Maybe one of the civilians attending the Corvette Expo must have thought it was an autographed freebie. Who knows.

Regarding my original post, I have zero play between the movement of the handle on the regulator and movement of the vent window. The play I was concerned with is only in the vent window itself. When partially open, the window has 3/4" of loose movement, i.e., play, slop, whatever, without the regulator handle moving. Based on you comment and other info I have received, I believe this amount of play to be within the allowance.

Thanks,
Charlie