need new capacitor for Mark V

[bvrsbro]

I recently acquired a Mark V serial #299990 and in the process of taking the old cracked power cord off, one contact point broke off of the capacitor. Does anyone know where I can get a new capacitor, Shopsmith? The #'s on it are 270mfd, 110vac, it's a Mallory. The motor is a GE 3/4 hp, 115v, 8.5 amp.. The cord was a two wire with no ground, wired to one side of the four wire toggle switch. I was going to replace it with a three wire cord. Would that be correct to do? I read the instructions to replace the cord but could not find any ground screw on the motor frame.
Did the older Mark V's come with a cord with only two wires and if so does that mean it's not grounded?
As may be obvious, I am not very savy on wireing a motor, but I am trainable! The motor was running aok but I didn't run it long because of the poorly frayed power cord..
Thanks for any input.
I'll try and upload some pics

[mcclainra]

Do a search on that Mallory part # and you will find a replacement. Unless you want that SS to be original I would seriously consider replaceing that motor with the newer 11\8 HP motor. They sell on ebay all the time.

[billmayo]

Do a Google search for 270-324 mfd 110-125 Volts Start Capacitor. Ebay also has them available for around $11 total.

I always replace any 2 wire power cord with a 3 wire cord (14 ga extension cord with the female end cut off for desired length (7'-10')). I ground the green wire under one of the nuts on the bolts holding the motor together.

I have found all the 1 1/8 HP GE motors (approx 10 so far) I have encounted has the insulation broken down on the wires inside the motor. I have had to replace the motor power cord (2 wire) on each of the GE motors and just finished one today.

Just my opinion, however I am a firm believer in the 3/4 HP motors as all my personal Shopsmith headstocks (Gilmer Drives) uses the 3/4 HP motor. I use the same motor and drive on most of the MINIs and SHORTYs I have sold. I have made many modifications to these early Greenie (no access hole) headstocks and have made jigs for this purpose.

[bvrsbro]

Do a Google search for 270-324 mfd 110-125 Volts Start Capacitor. Ebay also has them available for around $11 total.

I always replace any 2 wire power cord with a 3 wire cord (14 ga extension cord with the female end cut off for desired length (7'-10')). I ground the green wire under one of the nuts on the bolts holding the motor together.

I have found all the 1 1/8 HP GE motors (approx 10 so far) I have encounted has the insulation broken down on the wires inside the motor. I have had to replace the motor power cord (2 wire) on each of the GE motors and just finished one today.

Just my opinion, however I am a firm believer in the 3/4 HP motors as all my personal Shopsmith headstocks (Gilmer Drives) uses the 3/4 HP motor. I use the same motor and drive on most of the MINIs and SHORTYs I have sold. I have made many modifications to these early Greenie (no access hole) headstocks and have made jigs for this purpose.

That's what I wanted to know, I wasn't sure where to put the ground wire. I'm happy with the 3/4 hp, then again I havent used any other. I assume there is polarity +- on the capacitor to be maintained!? I do have the 3wire, 14ga 9ft cord. I was very surprised when I popped off the shopsmith cover and found no access hole!! Must make it hard to oil--any tricks on that? Thanks for the great advice.
Now to find the capacitor!

[billmayo]

That's what I wanted to know, I wasn't sure where to put the ground wire. I'm happy with the 3/4 hp, then again I havent used any other. I assume there is polarity +- on the capacitor to be maintained!? I do have the 3wire, 14ga 9ft cord. I was very surprised when I popped off the shopsmith cover and found no access hole!! Must make it hard to oil--any tricks on that? Thanks for the great advice.
Now to find the capacitor!

AC capacitors have no polarity. Place each wire on a separate capacitor spade (male) connector as most capacitors has dual spades for each input/output connector.

If no access hole is added, I recommend setting the Speed Control Dial/speed to maximum. Place in drill press position. Remove the belt cover and tie to the tie bar. I place about six drops of "Zoom Spout Turbine Oil around the exposed motor shaft and on the key.

Being careful, I place the zoom spout between the Control Sheave and Idler Sheave as close to the idler shaft (between a vane, not on the belt) as possible (directly under the idler shaft and between the belt on the sheaves). I put about 6 drops or more of oil into this location. Operate the motor and change speeds between FAST and SLOW a few times. Set speed back to FAST and repeat oiling and speed changes a second time.

I used to do this lubrication every year or so along with cleaning/blowing the crud and sawdust from the headstock. I was able to wear the motor belt down to a 1/4" width over 20 years before it needed replacement.

There are a few modifications to convert the Greenie (no access hole) heastocks. The first thing is to add oiling holes to the control sheave and the motor floating sheave when you get time to disassemble the headstock. I use a 3 1/4" carbite teeth hole saw centered between the 2 holes under the logo cover to drill the access hole (jig). I drill and tap a hole in the casing end above the eccentric bushing (jig) and use a body washer to prevent the idler shaft from exiting the headstock if the eccentric bolt becomes loose. I add 1" holes for checking the belt tension on each side of the casing direct in line with the Gilmer belt (jig). I redrill all the belt cover and motor pan screw holes for #10 SS metal screws and add a #8 U clip at each hole location.

[backhertz]

In my almost 40 years of electronic work, I have seen capacitors where maintaining polarity was important. It depends on the type of capacitor being used. Here are a couple of links below. This is just for info purposes:
http://en.wikipedia.org/wiki/Electrolytic_capacitor
http://www.piclist.com/images/www/hobby_elec/e_capa.htm

I haven't replaced a capacitor in 20 years except the electrolytics in my outside central AC compressor. Technology has evolved and component-level technology essentially died in the mid-80's when the military service stopped teaching basic electronic theory. Kids were being sent directly to duty stations without knowing how to bias a transistor on or off.

When I was a young technician in the Air Force, we would take a device known as a megohmeter (megger as we called it) and clip on to each post of a large electrolytic capacitor and crank away & build up a several hundred volt charge. Then we'd toss the charged capacitor around the shop until someone was bit or the boss came in... Crazy kids...

Tony

[bvrsbro]

Thank you to all. The help and knowledge on this forum is extensive and much appreciated. In the future I hope to make modifications to that old greenie. I have never heard of Zoom spout turbine oil. Where can I get some of that?
Thanks again.

[billmayo]

Thank you to all. The help and knowledge on this forum is extensive and much appreciated. In the future I hope to make modifications to that old greenie. I have never heard of Zoom spout turbine oil. Where can I get some of that?
Thanks again.

http://www.zoomspoutoiler.com/ is the original company that I always buy from. The long 6" spout pulls out and is really great for lubricating the headstock control sheave. I set the speed control to FAST and use 8-10 drops of oil for the control sheave. I also oil the motor floating sheave and motor shaft key at this time. I recommend only buying one bottle at a time as it takes a while to use all of the oil in the bottle. Shopsmith was using this product in the factory 2 years ago.

Ebay and Ace Hardware sells a Zoom Spout Oiler if the turbine oil is hard to find or has expensive shipping costs.

[JPG]

http://www.zoomspoutoiler.com/ is the original company that I always buy from. The long 6" spout pulls out and is really great for lubricating the headstock control sheave. I set the speed control to FAST and use 8-10 drops of oil for the control sheave. I also oil the motor floating sheave and motor shaft key at this time. I recommend only buying one bottle at a time as it takes a while to use all of the oil in the bottle. Shopsmith was using this product in the factory 2 years ago.

Ebay and Ace Hardware sells a Zoom Spout Oiler if the turbine oil is hard to find or has expensive shipping costs.

Any firm that sell/services electric motors(HVAC included) should have an acceptable capacitor in stock. The physical size may vary. The capacitance (270 mfd) and the working voltage(110v? ac) are the critical factors. The rated voltage may be higher. Try for 300 mfd. These capacitors are non-polarized. They are not electrolytic capacitors(them be polarized).

It MAY be possible to reattach the tab back onto the terminal. It was originally riveted. The terminal is probably aluminum.

Good Luck!

[bvrsbro]

Thanks. I've found a capacitor at a local Graingers and I'm off to Ace for the oil.