How to join (mend) a wire in a motor

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Deadeye

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I've been trying to mend this motor by changing the capacitor...but only buzzing. So opened it up.
The starter mechanism was pretty badly clogged with sawdust but the main issue is that one of the wires to the starter has broken and the sheath is very brittle.
The break is just below where the other wire inserts; apologies for poor camerawork.

Two questions:
1. Am I looking for a start capacitor or a run capacitor?
2. What's the best way to mend the wire? I can cut a couple of the brown bandings and get a short length clear I think, but soldering isn't my forte and seems likely that the remaining wire will also be brittle?

Many thanks! I have ordered a new motor for the saw, but shame to bin this one.
 

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1. Am I looking for a start capacitor or a run capacitor?
2. What's the best way to mend the wire?

Work out if the capacitor is switched out of circuit when the motor is running. If it is, it is a start capacitor.

An alternative way of saying this is if there is continuity in the capacitor circuit when the motor is stopped, it is a start capacitor.

The wire has likely failed due to fatigue caused by vibration. The extension of it that is bound up by the string would not have experienced that vibration. Rather than trying to join it at the break and have another fatigue failure, throw away the bit that is on the switch, go back a couple of inches and add a new, longer piece. The wire is likely enamelled so you have to scrape off the coating to permit the solder to stick (just fluxing it will not work). Whatever binding you remove, replace it (cotton string is acceptable). A bit of varnish once finished would also help (water-based polyurethane if nothing else available).

Best to use a high temperature wire (silicone sleeved or braided fabric). You could find some of this in an old cooker or hob or toaster, maybe a hair dryer. Sleeve the joint in the wire with some braided fibreglass sleeving, which you can often find included with halogen downlights. Not only will that give it insulation, it will also give some strain relief.
 
Work out if the capacitor is switched out of circuit when the motor is running. If it is, it is a start capacitor.

An alternative way of saying this is if there is continuity in the capacitor circuit when the motor is stopped, it is a start capacitor.

The wire has likely failed due to fatigue caused by vibration. The extension of it that is bound up by the string would not have experienced that vibration. Rather than trying to join it at the break and have another fatigue failure, throw away the bit that is on the switch, go back a couple of inches and add a new, longer piece. The wire is likely enamelled so you have to scrape off the coating to permit the solder to stick (just fluxing it will not work). Whatever binding you remove, replace it (cotton string is acceptable). A bit of varnish once finished would also help (water-based polyurethane if nothing else available).

Best to use a high temperature wire (silicone sleeved or braided fabric). You could find some of this in an old cooker or hob or toaster, maybe a hair dryer. Sleeve the joint in the wire with some braided fibreglass sleeving, which you can often find included with halogen downlights. Not only will that give it insulation, it will also give some strain relief.
Thank you; that's very helpful
 

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