The red button is a thermal protection device that is designed to open when
the air passing over it (motor heat) reaches a set temperature. This
prevents further temperature rise, and protects the motor's wiring
insulation.
The TP thermal protection button/switch won't reset until the motor cools
down to a reasonable temperature, so if the motor gets hot and the TP opens,
pushing the reset button won't reset the TP if the motor hasn't cooled
sufficiently.

Testing the TP can be done with an ohm meter or a battery powered continuity
tester. A continuity test is only to be done on circuits or parts with no
power applied.
An ohm meter check will show very low (near zero ohms) resistance, and the
continuity tester will light if the TP is closed, as it should be, at room
temperature.

If the TP has failed, you can probably get a suitable replacement at a motor
repair shop. There is most likely a temperaure marked on the part itself,
indicating the temperature rating.

For your extension cord, longer cords should always be a larger gage than
the power cord for motor powered equipment and other moderately heavy
loads.. heaters, welders, pumps etc.
Old extension cords can have loose terminal screws, weak contact pressure
and broken strands.

If the motor's centrifugal switch is making good contact, has a good start
capacitor and the TP is closed, and the motor doesn't start with the proper
voltage applied.. then it's very likely that the stator windings are damaged
assuming all other connections are secure).
If the stator windings are damaged, it's not going to be cost effective to
have the motor repaired.
If the pressure swich is faulty, that's a separate issue as far as
troubleshooting the motor (but you said it's been bypassed).

Check TP continuity.
Confirm that the centrifugal switch contacts are closed.
Motor should run with proper voltage.
Confirm that the new capacitor isn't faulty.

If you're uncertain of any of these comments, have an experienced and
qualified person check these items for you.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"dave" wrote in message
...
sprayed some welder tinware out in the yard, started cleaning the gun
afterward, notice pressure getting low, but I'm still plugged in, checked
everything...

a day later: bypassed the on/off switch, then bypassed that AND the
'blowoff' switch thing too ("for good measure"), still no go/all still VMB
(very much bricklike).

ordered, bought (and waited for) then installed, today, the new 'mcmaster'
capacitor (recommended here, thanks guys :-), but -still- no good. and,
yeah, I just 'assumed' the old capacitor was bad...(though "hoped" might
be the better word)

see some of the compressor glamor, or "lack thereof" at my site:
http://machines.2x.nu/air_compressor_krapped_out/


motor still belly-up, even with the new capacitor installed. what's the
reset button SUPPOSED to do and how do I know if it WORKS? tried that,
too, of course, to no avail. feels like a spring-loaded button pressing
against a steel plate "all ahead dead stop" or some damn thing.

tested the incoming 'hots', and they're live (neon test light) and the
electric is likewise live where the tiny spades push onto the motor male
spade connectors, inside the tiny stomach-shaped motor end-cap. they're
tight there, too. had that entire endbell off the motor a few days ago
too, to 'look it over in there' a bit: centrifugal switch contacts have
been lightly sanded (280 wet and dry/used dry) then cleaned with lacq
thinner on paper, so they're clean. functionally looks OK, motion and
slides good, no busted springs, all groovey. we're "good to go" in there.

get the motor specifics in this image:
http://machines.2x.nu/air_compressor...os/photo5.html

freakin' motor. need this thing. got some die grindering to do
'yesterday'. this *SUCKS*

one of those ol' craftsman "4 hp" motors with the 5/8ths shaft. 15 amp,
1.0 SF, 3450 RPM, capacitor start (but not capacitor run), single phase,
made by goulds-Century. needs to run Counter-C'wise when viewed facing
shaft end. probably cheaper to buy a 'new' (used) compressor COMPLETE than
a motor for THIS one. maybe we can work a swapfest?

if you have time to burn, see my "air compressor KRAPPED OUT" movie, too:
http://www.youtube.com/watch?v=TvmDd1nvdd0

anybody got an old "electric motors - troubleshooting them by their
symptoms" book?

thanks guys :-/

toolie the perplexed

Wild_Bill wrote:
The red button is a thermal protection device that is designed to open
when the air passing over it (motor heat) reaches a set temperature.
This prevents further temperature rise, and protects the motor's wiring
insulation.
The TP thermal protection button/switch won't reset until the motor
cools down to a reasonable temperature, so if the motor gets hot and the
TP opens, pushing the reset button won't reset the TP if the motor
hasn't cooled sufficiently.

Testing the TP can be done with an ohm meter or a battery powered
continuity tester.
I prefer using the "twin LED" tester I made, powered by an old walwart.
I just posted images of it...
A continuity test is only to be done on circuits or
parts with no power applied.
I like to wear soaking wet boots, lick salt, then put my tongue on one
terminal...and the arc welder on the other, on "high, straight polarity"
(livens up my day a bit :-)

An ohm meter check will show very low (near zero ohms) resistance, and
the continuity tester will light if the TP is closed, as it should be,
at room temperature.

If the TP has failed, you can probably get a suitable replacement at a
motor repair shop.
yeah, but I HATE paying retail, bill...and ENJOY 'reverse engineering'
too much to pay retail, or to use "the right stuff" when I can adapt
something else ENTIRELY (preferably out of my 'stash-heap') to do the
job. I mean like, if it's doable...

There is most likely a temperaure marked on the part
itself, indicating the temperature rating.
hmm, didn't realize that, I'm gonna go look, DERN good thing I haven't
yet reassemled it yet aGAIN...thank you bill :-)

For your extension cord, longer cords should always be a larger gage
than the power cord for motor powered equipment and other moderately
heavy loads.. heaters, welders, pumps etc.
Old extension cords can have loose terminal screws, weak contact
pressure and broken strands.
what about black tape? one of my cords has a slight rip I taped...I
think. that OK? you with OSHA? sometimes I use "odd color" tape too.
once I even used SCOTCH tape as an insulator... :-)


If the motor's centrifugal switch is making good contact, has a good
start capacitor and the TP is closed, and the motor doesn't start with
the proper voltage applied.. then it's very likely that the stator
windings are damaged assuming all other connections are secure).
If the stator windings are damaged, it's not going to be cost effective
to have the motor repaired.
the way I see it, if the motor has to even go in the DOORWAY of a motor
repair shop "that's all she wrote", never mind 'cost effective'. had ONE
motor rebuilt ONE time, and found out, years later, the problem wasn't
with the motor at ALL, but with the squirrel cage blower fanblade
*HUB*...yet, they TOLD me they "rebuilt" it, and charged me for it. they
only thing they "rebuilt" I think was my wallet, by thinning it out some....

remind me to tell ya the story of the time I took my radiator in, cause
my car was overheating. they said, and I thought, it needed 'rodding
out'. so I left it with them, the oldest radiator shop in town. get it
back, reinstall it, and months later, I'm still "running a bit hot",
even with the AC off. this was 'back in the day' when radiators were all
brass. this, of course, was after I personally tested, and/or
replaced/rebuilt all the 'more obvious' stuff, like water pumps,
thermostat, hoses, etc

so I took the frickin' thing out *AGAIN*, this time I used my oxi-acet
torch setup, and THIS VERY SAME AIR COMPRESSOR, to blow ALL the solder
out of one of the radiator endcaps, all the way around. I'd never ever
repaired a radiator before, or even seen one opened up. what'd I find?
take a guess? yup, those guys, my BUDDIES, never rodded it out, because
about 80 percent of the passages were clogged SOLID, and another 16
percent were partially clogged...so...I rodded the ****a out MYDAMNSELF,
with a thin piece of sheet metal. took a LONG time, too, it kept bending
(wasn't hardened, or even spring steel). but guess what? AFTER *my*
work, it runs WAY better and VASTLY cooler than after "their" work....

word to the weary: if you have a car with a brass radiator, and you're
'contemplating' having it rodded out: centerpunch both end solder seams
in a few places lightly, that way you can tell afterward if they EVEN
OPENED THE THING UP, LIKE IS *REQUIRED* FOR THE ROD-OUT procedure. or,
maybe the just repainted it...

woops, sorry, maybe I got carried away...

If the pressure swich is faulty, that's a separate issue as far as
troubleshooting the motor (but you said it's been bypassed).
yeah, and I meant it, too. it was bypassed. still is. I might bypass 90%
of the electrics on this heap, too, just to get it goin'....call me "the
ol' bypasser" ;-)

Check TP continuity.
Confirm that the centrifugal switch contacts are closed.
Motor should run with proper voltage.
Confirm that the new capacitor isn't faulty.
hmm, thought of that too. if it's a bad new one, maybe I can temporarily
replace it with my OTHER "bummer" capacitor, the old original one "of
dubious functionality" ? that be better? worse? a wash?

sometimes baffilation sweeps over bubbaland

If you're uncertain of any of these comments, have an experienced and
qualified person check these items for you.
if I can't do, bill, with help from you guys, it AIN'T gonna get fixed.
it'd be "end of story" for bubba's compressor. but, it'll get
fixed...yet. after a few days research lately, I've decided "newer"
compressors have little appeal: they make WAY too much noise, last WAY
TOO SHORT a time for what you pay for them, and their parts are made in
WAY TOO MANY distant lands, from 'weirdoleum' components. PLUS this one
is "right sized" for my needs, barely, but workable...I'd LOVE a bigger
one, two stage, but got no place to house it. I'd actually love a 90 hp
880 volt atlas-copco rotary screw, with a refrigerator-sized
dryer....but, then again who wouldn't?

thanks bill :-)

You've certainly got your money's worth out of the compressor in the time
you've owned it. The cost of the thermal protector is small compared to a
new motor, or new compressor.

The TP is what saves the motor when it gets hot, or the motor is heating due
to the voltage drop from an inadequate extension cord, or too heavy of a
load.
If your motor hadn't had the TP, it might've just burned the windings the
last time you used the compressor.

Fuses and circuit breakers aren't sensitive to the temperature of the motor,
so they can't replace the TP.
The cost of a new TP is the best insurance you can buy to protect the motor
from damage due to overheating in the future.

With a new capacitor and TP, and a little cleaning of the internal parts and
some oil for the bearings, you're not likely to have any other problems with
that motor for quite a while.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"dave" wrote in message
...

yeah, but I HATE paying retail, bill...and ENJOY 'reverse engineering' too
much to pay retail, or to use "the right stuff" when I can adapt something
else ENTIRELY (preferably out of my 'stash-heap') to do the job. I mean
like, if it's doable...

Wild_Bill wrote:
You've certainly got your money's worth out of the compressor in the
time you've owned it.
not quite yet...

The cost of the thermal protector is small
compared to a new motor, or new compressor.
well, yeah, bill, but I'm still shopping. the deal is, though: in the
entire 34 or 35 years i've owned it, I don't recall *EVER* pressing the
thermal reset button. and now, all of a sudden, right after I finish the
days spraying, whamo! it kraps out. compressor was indoors, in the
shade, same ventilation as usual, same cords and breaker, ambient air
temp same as usual, everything 'as usual' (except the "failed open" that
is).

I have the thermal protector 'jumped' now, I soldered a heavy wire
across the klixon termnals (though couldn't say for sure why I didn't
just REMOVE the thing entirely, and REPLACE it with the wire)

iggy suggested opening the TP up, noticed online good blowup drawings of
ones JUST like mine, by klixon, with a thin bimetallic disc inside, and,
apparently, a -tiny- epoxied center stud piercing the disc. also some
tiny contacts (which I like to clean and sand, on contactors and stuff).
I assume the tiny dark-red epoxied center stud is for the 'initial
factory adjustment', so, not having the right stuff to 'readjust' it
during a reassembly, I opted not to dismantle it (though still might).
seems to be running and starting OK, with the jumper wire "for the
moment anyway". I'm rewiring it today, the SO cords from motor to
pressure switch, and pressure switch to plug. also putting heavier gauge
from cord outlet end to the wall breaker (cord from wall was always 'a
bit warm' when I coiled it up at end of day).

thanks again and giant salute to royj our "capacitor size and source
suggestor and thermal suggestor fault KING", and to *all* you other
guys, and to you too stormin' - I'm still shopping for a better price on
the 'correct' klixon-thing for my application, but I might YET take you
up on the frige-overload protector thing :-)

The TP is what saves the motor when it gets hot, or the motor is heating
due to the voltage drop from an inadequate extension cord, or too heavy
of a load.
If your motor hadn't had the TP, it might've just burned the windings
the last time you used the compressor.

Fuses and circuit breakers aren't sensitive to the temperature of the
motor, so they can't replace the TP.
The cost of a new TP is the best insurance you can buy to protect the
motor from damage due to overheating in the future.

With a new capacitor and TP, and a little cleaning of the internal parts
and some oil for the bearings,
yeah. bearings sounded "a bit dry" when I first plugged it back in, with
the belt OFF, especially when it coasted to a stop...saw the numbers on
the side of the bearings, and ALSO "could have" measured them w/my dial
caliper, but *didn't* for unknown reasons...

so just call me the "open your compressor motor's endbell cover every
other day for some damn reason or another" guy

thanks again to ALL :-)
you're not likely to have any other
problems with that motor for quite a while.

now if I can figure out a way to get grease into sealed both sides motor
bearings withOUT ruining their seals...

dave wrote:
Wild_Bill wrote:
You've certainly got your money's worth out of the compressor in the
time you've owned it.
not quite yet...

The cost of the thermal protector is small
compared to a new motor, or new compressor.
well, yeah, bill, but I'm still shopping. the deal is, though: in the
entire 34 or 35 years i've owned it, I don't recall *EVER* pressing
the thermal reset button. and now, all of a sudden, right after I
finish the days spraying, whamo! it kraps out. compressor was indoors,
in the shade, same ventilation as usual, same cords and breaker,
ambient air temp same as usual, everything 'as usual' (except the
"failed open" that is).

I have the thermal protector 'jumped' now, I soldered a heavy wire
across the klixon termnals (though couldn't say for sure why I didn't
just REMOVE the thing entirely, and REPLACE it with the wire)

iggy suggested opening the TP up, noticed online good blowup drawings
of ones JUST like mine, by klixon, with a thin bimetallic disc inside,
and, apparently, a -tiny- epoxied center stud piercing the disc. also
some tiny contacts (which I like to clean and sand, on contactors and
stuff). I assume the tiny dark-red epoxied center stud is for the
'initial factory adjustment', so, not having the right stuff to
'readjust' it during a reassembly, I opted not to dismantle it (though
still might). seems to be running and starting OK, with the jumper
wire "for the moment anyway". I'm rewiring it today, the SO cords from
motor to pressure switch, and pressure switch to plug. also putting
heavier gauge from cord outlet end to the wall breaker (cord from wall
was always 'a bit warm' when I coiled it up at end of day).

thanks again and giant salute to royj our "capacitor size and source
suggestor and thermal suggestor fault KING", and to *all* you other
guys, and to you too stormin' - I'm still shopping for a better price
on the 'correct' klixon-thing for my application, but I might YET take
you up on the frige-overload protector thing :-)

The TP is what saves the motor when it gets hot, or the motor is
heating due to the voltage drop from an inadequate extension cord, or
too heavy of a load.
If your motor hadn't had the TP, it might've just burned the windings
the last time you used the compressor.

Fuses and circuit breakers aren't sensitive to the temperature of the
motor, so they can't replace the TP.
The cost of a new TP is the best insurance you can buy to protect the
motor from damage due to overheating in the future.

With a new capacitor and TP, and a little cleaning of the internal
parts and some oil for the bearings,
yeah. bearings sounded "a bit dry" when I first plugged it back in,
with the belt OFF, especially when it coasted to a stop...saw the
numbers on the side of the bearings, and ALSO "could have" measured
them w/my dial caliper, but *didn't* for unknown reasons...

so just call me the "open your compressor motor's endbell cover every
other day for some damn reason or another" guy

thanks again to ALL :-)
you're not likely to have any other
problems with that motor for quite a while.

now if I can figure out a way to get grease into sealed both sides
motor bearings withOUT ruining their seals...
Sealed or shielded, the former has rubber seals and the latter metal
shields. Both are easy to remove with care and a very small screwdriver
if nothing better. IIRC the sealed ones require more care as one
surface, normally the inner diameter is the rubbing surface, so prise
them out from the outer diameter of the seal. They snap back in easily
in my experience. If you look in a bearing catalogue there is a
differentiation between seals designed for an outer rotating or inner
rotating race, for motors the inner rotates which is the common case.

dave wrote:
Wild_Bill wrote:
You've certainly got your money's worth out of the compressor in the
time you've owned it.
not quite yet...

The cost of the thermal protector is small
compared to a new motor, or new compressor.
well, yeah, bill, but I'm still shopping. the deal is, though: in the
entire 34 or 35 years i've owned it, I don't recall *EVER* pressing the
thermal reset button. and now, all of a sudden, right after I finish the
days spraying, whamo! it kraps out. compressor was indoors, in the
shade, same ventilation as usual, same cords and breaker, ambient air
temp same as usual, everything 'as usual' (except the "failed open" that
is).

I have the thermal protector 'jumped' now, I soldered a heavy wire
across the klixon termnals (though couldn't say for sure why I didn't
just REMOVE the thing entirely, and REPLACE it with the wire)

Wild_Bill speaks the truth.

We know that the protector actuated once, Bubba. It saved you
a motor. You've finished troubleshooting but you haven't started
the repair yet! Please consider replacing the thermal protector so
you can get another 35 years safe use from your compressor.
Think of it as an insurance policy on your motor that costs
$0.86 per *year*.

Thanks!

--Winston

--

In the middle of some desert, is a gigantic pile consisting
of nothing but your ballpoint pens and spray bottles of
glass cleaner.

You get it, Winston. For Dave to hold onto the hope that a thermal protector
from a refrigerator or window A/C unit will suffice for his (greater HP) air
compressor motor, isn't likey to happen.

The peak starting current drawn by the air compressor motor will far exceed
the peak starting current of a fractional-HP household refrigerator or
window A/C unit.

The compressor motor's nameplate shows the HP as 4.0SPL (spl special). The
2-cylinder pump on the compressor can most likely easily be run with a 2 HP
motor (I owned a similar new compressor from Sears about the same time Dave
bought his), which is still considerbly larger than the motors in a typical
residential 'frige or window-sized A/C unit.

It's just far easier to get the correct part, which will fit properly inside
the motor (the only place it should be installed), and have the proper
protection.

I don't believe I've ever purchsed anything with the expectation that it
should or would work properly for over 30 years.

I could see myself using a 240VAC-rated TP device inside the motor, wired to
a properly-rated motor starter (inside a metal box) and secured to the
compressor.. IF a perfect replacement for the original part was NLA no
longer available.
But this method would very likely cost several times more than the
replacement part.

A lower voltage TP device (120VAC or lower starter coil control voltage)
would require the power cord to have a neutral conductor, and possibly a
stepdown transformer, to be wired properly.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Winston" wrote in message
...
dave wrote:
Wild_Bill wrote:
You've certainly got your money's worth out of the compressor in the
time you've owned it.
not quite yet...

The cost of the thermal protector is small
compared to a new motor, or new compressor.
well, yeah, bill, but I'm still shopping. the deal is, though: in the
entire 34 or 35 years i've owned it, I don't recall *EVER* pressing the
thermal reset button. and now, all of a sudden, right after I finish the
days spraying, whamo! it kraps out. compressor was indoors, in the shade,
same ventilation as usual, same cords and breaker, ambient air temp same
as usual, everything 'as usual' (except the "failed open" that is).

I have the thermal protector 'jumped' now, I soldered a heavy wire across
the klixon termnals (though couldn't say for sure why I didn't just
REMOVE the thing entirely, and REPLACE it with the wire)

Wild_Bill speaks the truth.

We know that the protector actuated once, Bubba. It saved you
a motor. You've finished troubleshooting but you haven't started
the repair yet! Please consider replacing the thermal protector so
you can get another 35 years safe use from your compressor.
Think of it as an insurance policy on your motor that costs
$0.86 per *year*.

Thanks!

--Winston

--

In the middle of some desert, is a gigantic pile consisting
of nothing but your ballpoint pens and spray bottles of
glass cleaner.

On 2009-10-20, Wild_Bill wrote:
I don't believe I've ever purchsed anything with the expectation that it
should or would work properly for over 30 years.

I have a 58 year old Quincy compressor, that works great, and I do
expect it to last 30 years for me. I will be 67, by that time, and the
compressor would be 88 years old if it lasts that long.

i

It would interesting/funny, I'd imagine, to know how much the compressor
sold for when it was new in 1951.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Ignoramus6669" wrote in message
...
On 2009-10-20, Wild_Bill wrote:
I don't believe I've ever purchsed anything with the expectation that it
should or would work properly for over 30 years.

I have a 58 year old Quincy compressor, that works great, and I do
expect it to last 30 years for me. I will be 67, by that time, and the
compressor would be 88 years old if it lasts that long.

i

On 2009-10-20, Wild_Bill wrote:
It would interesting/funny, I'd imagine, to know how much the compressor
sold for when it was new in 1951.


Good question. I have a promotional ad by Quincy from that time, it
asks "Is there compressed air on Mars? QUINCY COMPRESSOR, FIT INTO
YOUR FUTURE". It hangs on the wall behind the compressor.

http://igor.chudov.com/projects/Quin...ir-On-Mars-Ad/

Note also that, though the compressor is that old, I installed a new
single phase motor on it.

i

On Tue, 20 Oct 2009 06:47:59 -0500, Ignoramus21294
wrote:

On 2009-10-20, Wild_Bill wrote:
It would interesting/funny, I'd imagine, to know how much the compressor
sold for when it was new in 1951.


Good question. I have a promotional ad by Quincy from that time, it
asks "Is there compressed air on Mars? QUINCY COMPRESSOR, FIT INTO
YOUR FUTURE". It hangs on the wall behind the compressor.

http://igor.chudov.com/projects/Quin...ir-On-Mars-Ad/

Note also that, though the compressor is that old, I installed a new
single phase motor on it.

i
Dunno bout Quincys or Mars, but my Gardner Denver looks to be older
than me. I started out running it with two 1/4 HP motors belted
together, then an older 1/2 that needed the re-set poked about every
third start. now I have it on a 50Hz. half that seems to work OK and
drives the compressor at 535 RPM (Max. 600). I have a 3/4 in reserve
if I ever need it. I never realized how much I needed air until I got
it!
Gerry :-)}
London, Canada