sullair air compressor

[cmccain]

I have a 1996 sullair 185 air compressor that is shutting down after 7 minutes. Every single time. I have replaced the scavenger filter, the fluid, the hydraulic filter and the fuel shutoff solenoid. I have also had the oil cooler cleaned. I have also bypassed the temp sensor. The mechanical gauge is reading 260, but with a temp gun the max temp i am reaching on the air end is 220 degrees. This has very little to no electronics. It will start right back up and run a minute or two. Anyone have any ideas why this machine is shutting down?

 

[rmllarue91]

Does air compressor steadly rise and shut the compressor off at 260. I was told that when screw compressores bearings wear the tolerance lessons causing them to interfere generating heat. Makes sense but Idk if this I am common thing. Is the oil in compressor the right viscosity level and quality. Just a few thoughts let us know what u find.

 

[cmccain]

The compressor runs at a steady pace and turns off as if someone flipped the switch. I am running atf in the compressor and there was no change when I changed it. I talked to sullair and they said that was fine for the compressor, only good for 300 hours.

 

[rmllarue91]

It's most likely a safety shutting it down and does it only shut off when air temp is at or about 260

 

[cmccain]

it is the discharge oil temp that gets too 260. I have bypassed safetys to test and it will still shut down.

 

[rmllarue91]

Does it run for exactly the same amount of time ? about the only thing that will shut it off like that is fuel shut off controlled by a safety switch with or with out a timer. If they don't see a reference it starts the timer and when time runs out its break time. I in stall a fuel pressure gauge on most engine stall diagnostics Just to. Be safe.

 

[cmccain]

I have replaced the fuel shut off switch.

 

[Delmer]

I in stall a fuel pressure gauge on most engine stall diagnostics Just to. Be safe.

The fuel gauge is to be sure it's not a fuel starvation issue. Easier to put a test light on the injection pump so you can see if it still has power when it dies, (probably won't because it is being shut down, not dying, but that's what you want to confirm, if the power is being cut off "intentionally" or it's running out of fuel pressure).

No use chasing a control issue when it's not getting fuel, or vice versa.

 

[cmccain]

its not dying it is as if someone is turning the switch off. I know that the fuel pump is working correctly the fuel pump still has fuel if you take the fuel shutoff cover off. Also it can turn right back on, if it was fuel starvation it would have to be primed up.

 

[Delmer]

Does it run for exactly the same amount of time ? about the only thing that will shut it off like that is fuel shut off controlled by a safety switch with or with out a timer. If they don't see a reference it starts the timer and when time runs out its break time.

I'm no expert, but that seems like good advice. Lacking an expert or schematic, I'd hook the safeties back up and figure out which one is shutting it down.