Shop Floor Talk  

Go Back   Shop Floor Talk > Welding and Metalworking Forums > Shop & Safety

SFT Search:   
Reply
 
Thread Tools Display Modes
  #1  
Old 11-06-2011, 09:58 PM
NCMau NCMau is offline
Junior Member
 
Join Date: Oct 2011
Location: Fayetteville, NC
Posts: 12
Default Air Compressor Problem

I have a 2HP Craftsman shop compressor. Sometimes when the tank pressure reaches the low level, it tries to start and the motor overload kicks in. I changed the motor… didn't help, replaced the new check valve, didn't help either.The compressor head has a petcock which, I guess, eliminates the back pressure at restart. The petcock is open and it does what it supposed to do.
Unless there is something screwy internally, I have no clues on this problem. As I said, it doesn't do it all the time, but when it does, I have move the flywheel, then it starts again. Any suggestions would be welcome.
Reply With Quote
  #2  
Old 11-06-2011, 10:43 PM
H80N's Avatar
H80N H80N is offline
That Man Behind The Curtain
 
Join Date: Dec 2009
Location: NE Pa
Posts: 5,180
Default

if it is the old speedair style... you probably have a gummed up unloader.... take a pic of the pump and post it so we can see....
__________________
.
.

Pay no attention to that man behind the curtain..


The more you Know, The Better you Know, How little you Know (old Estonian saying)
Reply With Quote
  #3  
Old 11-07-2011, 03:16 PM
Jim-TX's Avatar
Jim-TX Jim-TX is offline
Chairman of the Headboard
 
Join Date: Oct 2006
Location: Abilene, TX
Posts: 2,413
Default

Are you running it on an extension cord? A compressor takes a lot of juice to get started. They won't work on a small cord.
__________________
Jim
Reply With Quote
  #4  
Old 11-07-2011, 05:19 PM
digr's Avatar
digr digr is offline
The Real Deal
 
Join Date: Apr 2005
Location: Duluth MN
Posts: 9,112
Default

Are you using 220 or 110 volts to the motor?
__________________
Drawing by Smartdraw
Reply With Quote
  #5  
Old 11-09-2011, 09:39 AM
NCMau NCMau is offline
Junior Member
 
Join Date: Oct 2011
Location: Fayetteville, NC
Posts: 12
Default Air Compressor Problem

To answer your questions:
The compressor is wired for 220V plugged to the wall and the proper voltage is available.
If I have to check the unloader, will it be accessible when the head is removed?
I have taken engines apart, but not compressor heads.
Attached Thumbnails
Click image for larger version

Name:	1.jpg
Views:	248
Size:	44.0 KB
ID:	83754   Click image for larger version

Name:	2.jpg
Views:	252
Size:	67.1 KB
ID:	83755  

Last edited by NCMau; 11-09-2011 at 09:58 AM.
Reply With Quote
  #6  
Old 11-09-2011, 11:00 AM
H80N's Avatar
H80N H80N is offline
That Man Behind The Curtain
 
Join Date: Dec 2009
Location: NE Pa
Posts: 5,180
Default Sears-enstein 2HP

Right now you have NO Unloader!!! somebody removed it.... no wonder it overloads and locks up...

From what I can see..... you have what may have been a Craftsman compressor at one time.... looks like the tank might be original......but not much else..
What you now have is a Frankenstein Mfg Co. Special....

where the unloader tube would have been on the head of the original pump... somebody put an automotive style radiator petcock...(on a similar but replacement pump). the unloader tube WOULD have gone down to a combination pressure switch/unloader..... which is now long gone.... looks like some crafty devil found a home water pump pressure switch at the hardware store and wired that in (unfortunately it has no unloader feature)

Here is a link to a similar (but 1hp Sears compressor) look for part #75 on the diagram

http://www.searspartsdirect.com/part...&prst=&shdMod=


and here is a link to the combination switch/unloader

http://www.searspartsdirect.com/part...PRESSOR&blt=11

switch is $84... by the time you are done it will be well over $100 plus your time... is it worth it to you?? I have a similar 1hp Sears that will be dedicated to plasma cutter duty... that I can photograph and post if you want to see what the unloader/switch looks like installed...
__________________
.
.

Pay no attention to that man behind the curtain..


The more you Know, The Better you Know, How little you Know (old Estonian saying)

Last edited by H80N; 11-09-2011 at 11:59 AM. Reason: clarity
Reply With Quote
  #7  
Old 11-09-2011, 11:57 AM
H80N's Avatar
H80N H80N is offline
That Man Behind The Curtain
 
Join Date: Dec 2009
Location: NE Pa
Posts: 5,180
Default unloader/switch

Here are a couple of pics to illustrate

#1 shows combination switch/unloader with tube coming down from compressor head.

#2 Shows unloader tube coming off of the compressor head (small aluminum tube where yours has the petcock)
Attached Thumbnails
Click image for larger version

Name:	compressor 003-c.jpg
Views:	241
Size:	98.7 KB
ID:	83756   Click image for larger version

Name:	compressor 004-c.jpg
Views:	240
Size:	100.9 KB
ID:	83757  
__________________
.
.

Pay no attention to that man behind the curtain..


The more you Know, The Better you Know, How little you Know (old Estonian saying)

Last edited by H80N; 11-09-2011 at 12:08 PM.
Reply With Quote
  #8  
Old 11-10-2011, 08:17 AM
NCMau NCMau is offline
Junior Member
 
Join Date: Oct 2011
Location: Fayetteville, NC
Posts: 12
Default Compressor Problem

Thanks for the info, H80N. I think the only Craftsman components of this compressor are the motor and the pump. When I bought it, it didn't have the a pressure switch, so I installed what I had in the shop, being ignorant about the unloader feature.
$100 for a Craftsman switch would not be worth for me to invest on this machine. I found couple reasonably priced combo units on bay. Do you have suggestions on the two? It looks like both of them would work.
Again thanks for the help.

http://www.ebay.com/itm/NEW-PRESSURE...ht_2102wt_1011

http://www.ebay.com/itm/Air-Compress...ht_2033wt_1011
Reply With Quote
  #9  
Old 11-10-2011, 09:20 AM
H80N's Avatar
H80N H80N is offline
That Man Behind The Curtain
 
Join Date: Dec 2009
Location: NE Pa
Posts: 5,180
Default

Since they seem to be identical in all other respects, even price if you factor in shipping... I would go with the 4 port just for convenience sake... just in case you want to install a pressure guage or reg there with it.... , worst case you install some brass pipe plugs in the unused outlets...

"NEW PRESSURE CONTROL SWITCH VALVE FOR AIR COMPRESSOR 95-125 4PORT W/ UNLOADER L4"

keep us posted...

Just as a side note... looks from your pics that this pump uses the heavy felt intake filter..... that is something that people usually neglect... they will clog and greatly reduce the capacity of the compressor.... it will work its heart out with lots of noise and heat but not produce much air.... they will get super clogged in a minute if they are around spray painting.(paint your car??)... Many people will take them out and replace with the oiled open cell foam that is used for lawnmower engines.... (hardware store or home center $3 cut to fit)

Second side note.... make sure you have enough clean oil in the pump... You would be amazed at how many people never even check it, let alone change it (I run Mobil1 Synthetic, with good results... others may disagree)
__________________
.
.

Pay no attention to that man behind the curtain..


The more you Know, The Better you Know, How little you Know (old Estonian saying)

Last edited by H80N; 11-10-2011 at 11:07 AM. Reason: addl info
Reply With Quote
  #10  
Old 11-11-2011, 01:07 PM
NCMau NCMau is offline
Junior Member
 
Join Date: Oct 2011
Location: Fayetteville, NC
Posts: 12
Default Compressor Problem

4 Ports switch on order. Notes are noted and will post results.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Web Search:

All times are GMT -5. The time now is 10:08 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2023, vBulletin Solutions Inc.