Old MKVII motor

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bigk01
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Location: California Central Coast

Old MKVII motor

Post by bigk01 »

I haven’t torn into it yet, but I was using my ‘67 mkvii last week with a small wire wheel in the chuck, when one time when I went to turn it on it wouldn’t run in the forward rotation. It just hums and vibrates.

It seems to run fine in reverse.

I’m hopeful that it’s maybe just the switch.

I would appreciate any thoughts or suggestions from the experts before I take it apart.

K
BigK
1967 MK VII with Band Saw, 6 x 48 Belt Sander, Jointer and many small accessories
Ridgid Contractors Saw
Delta 9” RAS
2 DeWalt MBF RAS’s
14” Delta Drill Press
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JPG
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Re: Old MKVII motor

Post by JPG »

bigk01 wrote:I haven’t torn into it yet, but I was using my ‘67 mkvii last week with a small wire wheel in the chuck, when one time when I went to turn it on it wouldn’t run in the forward rotation. It just hums and vibrates.

It seems to run fine in reverse.

I’m hopeful that it’s maybe just the switch.

I would appreciate any thoughts or suggestions from the experts before I take it apart.

K
Leave the motor alone!

Dive into the switch(not a pleasant task).

Do NOT do the hum test often nor 'longly'.

The contacts lose their spring with use/age.

VERY carefully 'form' the spring contacts.

If arcing has eroded the contacts, all bets are off.
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╟JPG ╢
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
bigk01
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Location: California Central Coast

Re: Old MKVII motor

Post by bigk01 »

Thanks for the reply.
Believe me the last thing I want to do is mess with the motor.
As soon as I get a little time, I will pull the headstock and try to rebuild the switch.
Thanks again,
K
BigK
1967 MK VII with Band Saw, 6 x 48 Belt Sander, Jointer and many small accessories
Ridgid Contractors Saw
Delta 9” RAS
2 DeWalt MBF RAS’s
14” Delta Drill Press
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beeg
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Re: Old MKVII motor

Post by beeg »

You don't need to pull the headstock. Just undo the nut holding the switch. BEFORE ya disconnect the switch, take a pic so ya know where the wires go back to.
SS 500(09/1980), DC3300, jointer, bandsaw, belt sander, Strip Sander, drum sanders,molder, dado, biscuit joiner, universal lathe tool rest, Oneway talon chuck, router bits & chucks and a De Walt 735 planer,a #5,#6, block planes. ALL in a 100 square foot shop.
.
.

Bob
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JPG
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Re: Old MKVII motor

Post by JPG »

beeg wrote:You don't need to pull the headstock. Just undo the nut holding the switch. BEFORE ya disconnect the switch, take a pic so ya know where the wires go back to.

ALL 8 or nine wires???? :D
╔═══╗
╟JPG ╢
╚═══╝

Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
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beeg
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Re: Old MKVII motor

Post by beeg »

JPG wrote:
beeg wrote:You don't need to pull the headstock. Just undo the nut holding the switch. BEFORE ya disconnect the switch, take a pic so ya know where the wires go back to.

ALL 8 or nine wires???? :D
YES!

or the next question will be "WHERE do these wires connect." :D :D
SS 500(09/1980), DC3300, jointer, bandsaw, belt sander, Strip Sander, drum sanders,molder, dado, biscuit joiner, universal lathe tool rest, Oneway talon chuck, router bits & chucks and a De Walt 735 planer,a #5,#6, block planes. ALL in a 100 square foot shop.
.
.

Bob
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everettdavis
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Re: Old MKVII motor

Post by everettdavis »

beeg wrote:
JPG wrote:
beeg wrote:You don't need to pull the headstock. Just undo the nut holding the switch. BEFORE ya disconnect the switch, take a pic so ya know where the wires go back to.

ALL 8 or nine wires???? :D
YES!

or the next question will be "WHERE do these wires connect." :D :D
I can help with that just a bit. https://www.shopsmith.com/ss_forum/view ... 90#p185690

Follow the My Google Drive link, select the "Mark VII - 1960's vintage" folder

When you start seeing things like these..... download what you need. It's Free

There are even some blank motor wiring diagrams in case your colors are different that allow you to define what you have. Pictures are good, but colors sometimes get sketchy.

Everett
Mark VII Stuff.png
Mark VII Stuff.png (192.77 KiB) Viewed 17106 times
StevenAyres
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Re: Old MKVII motor

Post by StevenAyres »

bigk01 wrote: one time when I went to turn it on it wouldn’t run in the forward rotation. It just hums and vibrates.
I had the same experience shortly after I started using my VII. After checking out the wiring carefully, I narrowed the problem down to the start capacitor. Mine was a GE motor.
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JPG
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Re: Old MKVII motor

Post by JPG »

StevenAyres wrote:
bigk01 wrote: one time when I went to turn it on it wouldn’t run in the forward rotation. It just hums and vibrates.
I had the same experience shortly after I started using my VII. After checking out the wiring carefully, I narrowed the problem down to the start capacitor. Mine was a GE motor.
Ah, but, his only fails in ONE direction, hence the switch is de prime suspect.
╔═══╗
╟JPG ╢
╚═══╝

Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10
E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
bigk01
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Posts: 13
Joined: Tue Jun 09, 2015 10:17 am
Location: California Central Coast

Re: Old MKVII motor

Post by bigk01 »

Thanks again to everyone who has replied.
I just took a quick look and I can’t see anyway to get at the switch without talking the headstock off the rails. It doesn’t look like the motor cover will drop between the lower tubes.
Am I missing something?
It’s a little tough wrestling the headstock by myself, but I have done it before.
BigK
1967 MK VII with Band Saw, 6 x 48 Belt Sander, Jointer and many small accessories
Ridgid Contractors Saw
Delta 9” RAS
2 DeWalt MBF RAS’s
14” Delta Drill Press
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