Question on a JOY Pull Behind Compressor

[Scott(MO)]

Hello,
Recently I bought a late 70's JOY Pull Behind Compressor. When I looked at it at the shop that I bought it from, it ran good but was cold natured. After I got it home, I went to start it up and it started right up. The problem is that it died and began to puke oil out the Air Breather. Anybody ever experince this?
 

[Bert g]

Could be one of three things. Not setting level. Plugged separater element. Return line plugged.
 

[Dalex]

I remember that symptom in the fleet we had , The seperater is a good place to start.Drain the water out of the hyd tank, I think you pull a sensor to get to the lowest spot Those are great compressors, parts are handled by Sullair , but Baldwin filters makes the seperater if you want to save $100 ....
 

[XRogerX]

A small correction. I believe Sullivan, not Sullair, took over the Joy portable line.


I took a pretty good oil bath from a Joy shop compressor once when it shut down on overload with the inlet valve wide open. It sounds like your machine may be similarly shutting down due to a fault. The very first thing I would check is the thermal mixing valve, as it will cause the compressor to shut down on over temperature, even if it is cold outside. I would also check for a plugged fuel filter if it dies slowly, or lacks power.

Is this a screw or a vane?

If this is running an old 2-stroke Detroit, make sure there is some provision to cut off the air to the motor, as the compressor end can spin the motor backwards at shutdown and cause a reverse-rotation runaway condition under some circumstances.

I"m not sure what you mean by "cold natured". Every portable compressor should be left to idle for awhile when they are started cold, not just for the usual reasons, but there may be ice in the separator and controls which should be given time to melt.
 

[Scott(MO)]

Thanks for all the info. The compressor engine is a IH 4 cyl with a rotory screw (I think). I've ordered a manual for it, but haven't gotten it yet. I started it again and let it warm up for about 15-20 minutes and when I engaged the loader valve (I think that's what it is called, it ran good and then when I turn it back it died, but it didn't puke any oil this time. I started back up and it ran fine after that with no problems.
It's a little low on oil so I need to get some oil in it before I run anymore. What oil do you suggest for the screw unit?