Stewart Model 114-A horn repair

[Mike Royster]

Has anyone here repaired one of these plunger type horns? It works on occasion, the plunger will go down 3/8 of an inch and stop. If you move it around a bit it might work a few times then stick again. I have taken the horn shell off and lubricated the gears but to no success. Anyone familiar with this horn? I see no missing teeth and no obstructions. To take it further apart you can remove the 4 screws that hold the body in place, but the plunger would have to be removed some how. Thanks much for the assistance!
Mike

[Rich Eagle]

I don't know if anything here would help but here it is:
https://www.mtfca.com/discus/messages/8 ... 1542653969

[ThreePedalTapDancer]

I bet an inner gear has come loose from its mooring. You have to look carefully at which gear is binding. The back inner gear can go off it’s tracking and bind up the gears, especially if the gear housing is damaged or cracked from forcing the plunger. The plunger is removed after pushing it all the way down and removing a stop screw at the bottom of geared shaft. Then pull out plunger and remove gear housing. The red arrow points to where the back gear axle rides, and this can be cracked or worn to the point that the gear goes off kilter and binds others. You can’t see up unless you pull gear housing out.

IMG_1846.jpeg (62.1 KiB) Viewed 511 times

[Mike Royster]

Thanks to both of you for the info, I really appreciate it!