Ingersoll p185 running hot & oil is now dark

Published Categorized as Air Compressor Overheating, Air Compressor Troubleshooting, Ingersoll Rand 2 Comments on Ingersoll p185 running hot & oil is now dark

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by joseph hanselman
(Victoria, tx)

Hello I have a 185 that is doing similar actions as others. Have done a complete service , bypassed sensors, and the unit still runs hot and shuts off shooting code 5.

But then I’ve had various other codes shot as well.

The thing that has me worried is the ae oils that was fresh has discolored making me think bearings are out and causing motor to over work. Any help would be wonderful.

Ingersoll Rand P185 Tow Behind Compressor
Ingersoll Rand P185 Tow Behind Compressor


by: Doug in

Have you been running this a while, or is it “new” to you?

If “new”, any idea how long did it sat?


by: joseph hanselman

No sir it’s a customers unit. I am about out of ideas for it.
So far

Turbo has been replaced due to damage from them running the machine without fileters

Complete service on all filters and fluids

Have received codes


Pressure regulator and lines cleaned (pressure regulator is another suspect part)

The machine was sold by us in 2014 when it came here begging on july 17 it still had our filters.


by: joseph hanselman

I have now removed inlet valve and discovered lots of metal deposits most likely from the bearings.

Very sad…I guess this is to be expected when a person for some reason decides to not use any filters whatsoever while sand blasting with the compressor doors open…


P185 running hot – bearings
by: Doug in


Thanks for the update, and let us know what happens next, please.


by: joseph hanselman

I’m still perplexed by this machine. the machine produces air wonderfully and constant. it builds air and holds at 110 psi during idle, when service valve is open produces 70psi constant. its only when you go to shut down service valve (slowly not slowly doesn’t make a difference) is when the engine dies.

I suspect inlet valve but have inspected both springs polished piston rod and piston.inlet valve is closed when not in service. If the bearings where out wouldn’t the machine die during idle? It has to be something that involves the closing of the service valve.

rpms of machine are dead on until the closing of the service valve. then there is a drop in rpms. making me think not the air end valve is not closing properly…thank you for any help. and pray its not the bearings please.

is there a possibility of bearings being torqued allowing oil to low back and bog down machine?


70 psi?
by: Doug in

That says to me one of two things, if the RPMs are right:

The airend is shot. Perish the thought.

The inlet valve is not opening fully, nor closing fully – not opening causing low pressure, and not closing leaving partly loaded, causing it to die.

Or, maybe both. Ugh.

BTW, isn’t one supposed to run this doors closed?


Update – still an ongoing problem
by: joseph hanselman

Well after 5 flushes the air end oil is now staying beautiful.

The coupler has been replaced.

The bearings have been checked and they actually some how have survived the abuse from the owner.

Every line has been removed and cleaned.

All filters affected from air end oil have been replaced.

Machine will now function properly until something it warms up. Then it’s back to shutting off when ever service valve is shut off. Prior to running for about 15 minutes you would never guess there is a problem…. but then after 15 minutes. The engine will begin surging and then if valve isn’t opened the machine dies. Going back to the inlet valve. Rechecking regulator. I did have to reset idle and operation speed after all the lines where cleared from debris.


Oil cooler?
by: Doug in

Maybe 15 mins to oil bypass opens? Don’t see how that’d cause your problem, but with everything else…


Oil cooler
by: Anonymous

It’s not out of the realm of possibilities the amount of grit that came out….breaks the heart. These poor people would probably fare better buying a new unit….I would.

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2010 doosan p185 WJDU compressor has no air build up at all. with engine not running can press open unloader valve with finger but with engine running valve is closed. tried pushing open with finger, wont open, what do i do next

No codes on display?
Oil level?
Has it worked in the past for you?
Done any maintenance recently?
Is it level?