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by John

The compressor unit will start and run ONLY if all the air valves are OPEN.

When the valves are in the closed position the unit will build 40-60 PSI before the unit bogs down to the point of shutting off.

The unit will not restart until all the air pressure has been bled out of the system first.

We are in a deployed location and do not have access to a Technical Manual for this unit. Any help would be highly appreciated. Thank-you

Ingersoll Rand 185 air compressor
Ingersoll Rand 185 air compressor


Engine bogs down and dies under load
by: Doug in s.d.ca

So, if you get it started with the valves open, can you close it slowly – and does the engine rev at all? Is that how you get the 40-60 psi?

Main things (which I imagine you already checked)

Clogged air or fuel filter, low/bad fuel.

Linkage to throttle.

check out




by: John

Hello Sir,

You are correct, we start the compressor with the valves open and the motor will run at high rpm, when we as we close the valves (which would build up air pressure in the tank) you can hear the motor drop rpm as it builds this pressure to the point that the motor itself cannot maintain rpm nor idle.

The result of closing the air valves is that the motor stalls.

Air pressure being observed is about 60psi before the motor actually quits.

We have checked everything you described, and we don’t believe it’s a safety system triggering the stall because we are getting good constant power to the the Fuel pump, while replicating the stall condition we observe the voltage to the pump.

In short, at no point does the fuel pump loose power, so we know it’s not any system shutting down the fuel supply.

We have also pulled the unloader valve off to see if everything was kosher and it was clean.

Again any help would be appreciated, if you have questions we are more than happy to oblige.

Thank-you Doug.

Very Respectfully: John


I-R 185 bogs
by: Doug in s.d.ca

Well, first thing is that the engine needs more fuel as the load increases – and it’s not getting it.

Throttle linkage

Fuel rail pressure / volume (filters)

Bad fuel

Restricted air intake

That given that the air end is not suffering from bad bearings and binding as the pressure goes up.