Looking for help here. I have an older Mark V that I have upgraded several times but nothing to do with the motor. It was purchased in 1981. The problem is the motor and don't know if I need a rebuild or not. The motor doesn't hum or buzz so I don't think it is the motor itself. The motor will start up sometimes and run for a few minutes taking its time to come up to speed. Then i start cutting and it trips a breaker. It will reset immediately and the same thing happens. Then the next time it runs fine.
Sometimes I will turn on the switch and it won't start at all. Play with the switch a bit then...it fires up.
Is this a switch or capacitor problem or worse...a motor problems. All suggestions welcome.
Thanks.
Power Problems
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Danimal713
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Re: Power Problems
It is possible there are more than one problem. The switch could be intermittent and why it sometimes does not start. Pulling switch and using an ohm meter to test would be a starting point for that or since not expensive now is good time to replace. I have seen older machines do this and dust gets inside and sometimes blocks the contacts from making.
This would not explain what you describe is happening with the motor. This sounds also like possibly more than one problem. Not starting if switch passes 120 VAC to motor usually they hum but do not turn. This can be a problem with start windings. On several I have been into, there was so much dirt around the contacts for start winding it could never make contact and no start winding means no turnie on for motor. So disassembling motor is next action. Care should be taken getting the spring off the motor shaft. I made a jig to capture it using clamps. I used a 5/4 scrap cedar left over from a deck project and bored a hole that allowed the shaft of the motor to go through. On backside I counter-bored a hole that allowed the large washer to be captured. (Actually now I remember do the counter bore first, then drill the hole for shaft to not loose the centering of the holes). Then fit jig over shaft and capture washer and compress spring to allow motor shaft to stick out to access the retainer. CAUTION- once retainer is off, the spring has a lot of stored energy and where clamps come in. BEFORE compressing spring, put on clamps to control the spring when it uncompresses. Then you can disassemble motor. Now is a great time to replace bearings in the motor also since you will have it apart already. There are several styles of start winding switches. But a good cleaning is good to do nd might fix it. If the windings in the motor are bad, then best get a new motor. The popping a breaker means it is pulling too much current. Maybe a good cleaning and checking for worn bearings might fix it - hopefully it is not shorted or open windings. I have heard of people describing taking motor to a shop that specializes in rebuilding motors but I do not have any experience with that but a reputable shop should be able to give you an accurate price to compare to getting a replacement motor. A capacitor problem is also possible.
The slow to start can be belts or motor windings. You did not say which motor and what year so there are a few unknowns. Older machines have 3/4 HP motor (unless it has been replaced with a 1 1/8 HP later). A stretched lower drive belt or very loose poly belt can cause slow spin up.
Hopefully these will point you in a direction to find the fix and get it working well.
This would not explain what you describe is happening with the motor. This sounds also like possibly more than one problem. Not starting if switch passes 120 VAC to motor usually they hum but do not turn. This can be a problem with start windings. On several I have been into, there was so much dirt around the contacts for start winding it could never make contact and no start winding means no turnie on for motor. So disassembling motor is next action. Care should be taken getting the spring off the motor shaft. I made a jig to capture it using clamps. I used a 5/4 scrap cedar left over from a deck project and bored a hole that allowed the shaft of the motor to go through. On backside I counter-bored a hole that allowed the large washer to be captured. (Actually now I remember do the counter bore first, then drill the hole for shaft to not loose the centering of the holes). Then fit jig over shaft and capture washer and compress spring to allow motor shaft to stick out to access the retainer. CAUTION- once retainer is off, the spring has a lot of stored energy and where clamps come in. BEFORE compressing spring, put on clamps to control the spring when it uncompresses. Then you can disassemble motor. Now is a great time to replace bearings in the motor also since you will have it apart already. There are several styles of start winding switches. But a good cleaning is good to do nd might fix it. If the windings in the motor are bad, then best get a new motor. The popping a breaker means it is pulling too much current. Maybe a good cleaning and checking for worn bearings might fix it - hopefully it is not shorted or open windings. I have heard of people describing taking motor to a shop that specializes in rebuilding motors but I do not have any experience with that but a reputable shop should be able to give you an accurate price to compare to getting a replacement motor. A capacitor problem is also possible.
The slow to start can be belts or motor windings. You did not say which motor and what year so there are a few unknowns. Older machines have 3/4 HP motor (unless it has been replaced with a 1 1/8 HP later). A stretched lower drive belt or very loose poly belt can cause slow spin up.
Hopefully these will point you in a direction to find the fix and get it working well.
Re: Power Problems
If it is a GE motor the wires from the switch to the motor are known to have problems with th insulation. It breaks down and flakes off and can cause a short which will cause a breaker to trip.
Bill V
Bill V