I aquired an Elgin convertible yesterday.16 size,11 jewels,serial number 1492373.Winds right up and runs with good motion.Gained 30 minutes over night.Would needing cleaned make it run that fast?It doesn't look that dirty.Thanks for any help.Norm

Norman,
First..I would check to see if maybe one of the screws on the balance wheel is missing..Look to see that each screw on the balance has a matching screw on the opposite side of the balance wheel...

In addition to what Gary suggested, demagnetize the movement, check to see if the outer hairspring coil is between the regulator pins, make sure the hairspring isn't touching the bottom of the balance cock or balance arms. Make sure none of the coils on the hairspring are touching or have any oil or residue on them.

I've had a couple watches where the hair spring had coils stuck to each other reducing the effective length of the spring, making it run fast.

A careful cleaning and inspection of the spring fixed them right up. The Navy Watch Makers Manual TM9 helped a lot.

Upon close inspection I found the hairspring wasn't between the regulator pins.I'll let it run another 10 or 12 hours and make sure that's what it was.Thanks guys for your help.I'll post some pictures later.It's a nice watch.Regards.Norm

Since its an 11 jewel movement some of the pivots are in metal. Unless you know the service history I wouldn't run it a lot without a cleaning.

Good advice Jim.That's my next project.Here are a few pictures.It is in Jas.Boss dust proof,spring back case. I tried to get a shot of where it is signed.I've not ever seen one before.No other screw marks,looks original to case.Norm

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