Help getting Sanborn air compressor working.

Reply

  #1  
Old 12-14-13, 09:38 AM
Q
Member
Thread Starter
Join Date: Dec 2013
Location: US
Posts: 8
Received 0 Votes on 0 Posts
Help getting Sanborn air compressor working.

Hi Guys,
I have an air compressor that my dad gave to me many years ago.
Sanford Manufacturing
Model 104A200-22
22 Gallon Tank
2 hp motor

It sat until now, And I see it has broken pressure switch ass'y.
And tubes were missing.
I ordered a new pressure switch,
New Pressure switch for air compressor 95-125 single port w/ unloader & on/off lever - Amazon.com

I installed it like this,
Compressor Tubing Photo by Qmavam | Photobucket

Here's a blowup diagram of the original.
http://www.mastertoolrepair.com/imag...ssor_parts.jpg

The unit will run 5 to 10 seconds, stall, then pop the circuit breaker.
The air compressor puffs air out of the air intake.
If I disconnect the small (unloader tube) from the pressure switch,
the motor will continue running without a problem. The puffs out of the
air intake also stop. Because the unloader outlet is open the tank
doesn't pressurize. This shouldn't be difficult, but I'm not seeing
the problem here!
Any ideas what I have wrong, or what could be wrong?
After posting I see my links don't work, how do I fix them?
Thanks to GregH for helping me fix my links.
Thanks, Mikek
 

Last edited by Qmavam; 12-14-13 at 10:22 AM.
  #2  
Old 12-14-13, 10:01 AM
GregH's Avatar
Super Moderator
Join Date: Jan 2001
Location: Manitoba
Posts: 10,163
Received 43 Votes on 41 Posts
Welcome to our forums!

You can not use a tinyurl or similar address for links.
The address has to include the site name.
You can use the insert image button above the dialog box.
Here are detailed instructions.

It kind of sounds like whatever you have installed has caused the discharge line to be blocked.
If the check valver were installed backwords you would see the symptoms you are having.
 
  #3  
Old 12-14-13, 10:26 AM
Q
Member
Thread Starter
Join Date: Dec 2013
Location: US
Posts: 8
Received 0 Votes on 0 Posts
Thanks for the help with the links.

I did not install a check valve, I'll look at the drawing, if it goes between the compressor and the
tank, it makes sense to me, why I have a problem.
Mikek
 
  #4  
Old 12-14-13, 10:36 AM
Q
Member
Thread Starter
Join Date: Dec 2013
Location: US
Posts: 8
Received 0 Votes on 0 Posts
Ok, further reseach shows there is supposed to be a check valve installed.
I'm off to see if I can find one locally.
Thanks, Mikek
 
  #5  
Old 12-14-13, 10:40 AM
GregH's Avatar
Super Moderator
Join Date: Jan 2001
Location: Manitoba
Posts: 10,163
Received 43 Votes on 41 Posts
Yes but the lack of a check valve would not likely be your problem and there may very well be one there.
They are sometimes just a small ball check inside a non-descript fitting.

Post the pics before you do anything.
 
  #6  
Old 12-14-13, 10:51 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 60,786
Received 1,326 Votes on 1,225 Posts
I had the same exact compressor. I bought it from my traveling Snap On guy. Cost me a lot of money. I needed one quick and they sold them on payments back then.

Anyway... I pointed to the check valve in the picture. After going thru three of them in the first year, I ended up buying one that had a teflon check ball in it. The original valves had what looked like a hard rubber ball and all leaked air on shutoff making it impossible for the compressor to restart or hold air.

In the course of the 10 years I used it.... that teflon check valve never wore out but I did end up going thru several reed plates. These compressors run hot.

My two horsepower motor was a power pig. I rewired mine and ran it on a 20A 240v circuit as the motor used more power than I could supply it on 20A 120v circuit.

Name:  comp.jpg
Views: 4958
Size:  35.1 KB
 
  #7  
Old 12-14-13, 11:15 AM
GregH's Avatar
Super Moderator
Join Date: Jan 2001
Location: Manitoba
Posts: 10,163
Received 43 Votes on 41 Posts
One reason many of these compressors run hot is that the mfr installs too small a discharge line between the heat and check valve.
Is that 1/2" od copper tube on yours Pete?

You might find it will run a lot cooler if you up-size that line and fittings at least one size.
 
  #8  
Old 12-14-13, 12:56 PM
F
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,495
Received 36 Votes on 28 Posts
Good point, Greg. It looks to me as if that is only a 3/8 inch discharge line and the compressor head has either a 1/2 or 3/4 inch tapping bushed down to 3/8 inch.

Qmavan, you can disconnect that discharge line and see if the compressor will continue running. I wouldn't be at all surprised that you find the check valve at the tank stuck shut and even the compressor valves could be sticking after all those years in storage.
 
  #9  
Old 12-14-13, 02:07 PM
Q
Member
Thread Starter
Join Date: Dec 2013
Location: US
Posts: 8
Received 0 Votes on 0 Posts
Thanks PJMax and Furd and GregH,
I don't understand the check valve. I removed the large tube from the compressor
and tried to blow into it. I can't! Which means the check valve is preventing the compressor from filling the tank.

Here's a picture of the lower half of the check valve.



Here's the lower half of the check valve with the ball installed.


Here is the top section of the Check Valve and the ball.




For this to make sense to me, the ball should have a spring pushing it against
the top piece.
What do you guys think?
Thanks, Mikek
 
  #10  
Old 12-14-13, 02:24 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 60,786
Received 1,326 Votes on 1,225 Posts
That compressor is gone now but I'm pretty sure it was 3/8" line. That makes sense now with the restriction. That line would get red hot and smoke the check valves.
 
  #11  
Old 12-14-13, 02:35 PM
GregH's Avatar
Super Moderator
Join Date: Jan 2001
Location: Manitoba
Posts: 10,163
Received 43 Votes on 41 Posts
Can't really make out what you have there by the pictures.
It doesn't make sense because the ball appears to be against a seat but in the wrong direction.

What you have looks like a combined check valve/mainifold.
You are not likely to find parts for that and may have to either get an exact replacement or try to adapt standard parts.

Some better pictures of the whole assembly might help.
 
  #12  
Old 12-14-13, 03:03 PM
Q
Member
Thread Starter
Join Date: Dec 2013
Location: US
Posts: 8
Received 0 Votes on 0 Posts
I agree it seems like it in the wrong direction. It makes me think it is missing a spring.

You're right, the lower half of the check Valve is built into the a manifold.
Here's the picture.


Not sure what else I could show to help in understanding.

Does everyone agree that the ball should be in the upper portion of the valve.
As I see it. it's job is to keep air from coming out of the tank back to the compressor,
so it needs be in the upper portion of the valve.

Thanks, Mikek
 
  #13  
Old 12-14-13, 03:29 PM
GregH's Avatar
Super Moderator
Join Date: Jan 2001
Location: Manitoba
Posts: 10,163
Received 43 Votes on 41 Posts
OK.
There should be something keeping the ball from sealing when air is flowing from the pump.
When the compressor stops the air trying to flow back into the pump moves the ball upwards, closing against a seat to keep the tank from draining through the compressor.
There is normally a spring to help the ball move upwards into the closed position.

If it seals when in the down position something is either worn, broken or missing.
Perhaps it was a circular shaped spring that would allow air to flow past the ball.

Edit: I checked this diagram and it does show a spring under the ball.......[Maybe it's laying on the floor or bench! ]
 
  #14  
Old 12-14-13, 03:38 PM
Q
Member
Thread Starter
Join Date: Dec 2013
Location: US
Posts: 8
Received 0 Votes on 0 Posts
This is a poor picture but good enough to show there is supposed to be a spring.



The spring is not listed as a part for sale and the manifold is not available.
I'll call Monday just to make sure they don't have the spring.
I will see if I can find a suitable replacement.

Extra cudos to PJMax for posting the pic of where the check valve was. I stuck a drill bit down the piece and it went to far, making me think, "that's not a check valve" after your picture I decided to take it apart and there was the ball, just not up where it should be.

Thanks to everyone, Mikek
 
  #15  
Old 12-14-13, 03:41 PM
Q
Member
Thread Starter
Join Date: Dec 2013
Location: US
Posts: 8
Received 0 Votes on 0 Posts
"I checked this diagram and it does show a spring under the ball.......[Maybe it's laying on the floor or bench! ]"

I wish it was that easy :-)
Our posts crossed, you'll see I posted a diagram showing the spring.
Thanks for all the help, Mikek
 
  #16  
Old 12-14-13, 03:47 PM
GregH's Avatar
Super Moderator
Join Date: Jan 2001
Location: Manitoba
Posts: 10,163
Received 43 Votes on 41 Posts
You might be able to find a spring at an auto parts store.
It is very light, not much more force than a ball point pen spring.
A light spring of the correct diameter cut so it is only about three or four coils high would do it.
The
 
  #17  
Old 12-14-13, 05:48 PM
Q
Member
Thread Starter
Join Date: Dec 2013
Location: US
Posts: 8
Received 0 Votes on 0 Posts
I went to Home Depot, found a kit with 84 springs. I picked the spring I thought was the
right diameter, not much force and installed it. I plugged it in and pumped right up to 125psi.
To much, I adjusted the pressure switch for 105/80 and everythingis good.

Thanks to all, really appreciate all the input, Mikek
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: