Outdoor Power Equipment and Small Engines - Craftsman Air Compressor

I just finished replacing a piston assembly & check valve on this horizontal 2hp craftsman air compressor that is probably 10 yrs. old or so. Works fine but the problem is that it reaches 120PSI and will not move any higher nor will the unit shut off until I unplug it. There is no air leaks. Any suggestions other than buying a new one ?

This unit has a 135PSI max.


Please Repond.


Thanks.

That's not a model I have worked on, but I'm sure you have a regulator on it with a cutout to shut off the compressor when it reaches a specific air pressure in the tank. That would have electrical contacts in it that would open or close whether kicking the compressor on or off, whichever the pressure in the tank called for.

In many models those are adjustable , yours may or may not be.

That regulator could be bad and not able to do its job, or..it could be out of adjustment relative to the upper end of the air pressure attainable by the compressor. Your compressor, in its present condition may not be able to pump to the air pressure set in the regulator. Consequently it can't kick it off.


Hope this helps

Butch1957,

marbobj pretty much summed it up.

Did you deglaze the cylinder when you replaced the piston?
Also, when you say you replaced the check valve do you mean reed valve(s) in the head or the check valve on the discharge line at the compressor?
What was wrong with the old piston and valve?

If you can readjust the pressure control setting it for 100 psi would make it work for you.
Most air tools are rated at 100 psi.

Model : 919-167.141

How do you adjust the pressure control setting on this type of unit ? I agree Greg, if I can set it at 100PSI then this may solve the problem.

Thanks for any input.

Butch:

Here is a link to a general diagram of your compressor. They show the regulator and pressure switch in different components. The part you need to look at is the # 9. If yours is adjustable it would be either accessible from outside this cover or you may need to pop the cover off. You would be looking for something like a screw with a lock nut on it.

If you find something similar to that on or in the pressure switch (#9) I would loosen the locknut and start your compressor. When the pressure builds to about 80 or 90 pounds turn the adjustment screw either in or out until the compressor stops. You may have to play with it to figure it out.

http://www3.sears.com/imaging/ImagePageJava.shtml?productTypeID=0703000&brandID=0247&modelDesc=AIR%20COMPRESSOR&modelNumber=919167141&documentID=P0070030&documentTypeID=PLDM&documentClassCode=PM&titleType=AIR%20COMPRESSOR%20DIAGRAM&titleID=00001&

If it comes out ok tighten the locknut when you get it set to the 100 lbs or where you want it to shut off.

Let us know how it works out.

Hope this helps