Troubleshooting Compressors One

This wesite has received hundres of questions about troubleshooting air compressors.

In an effort to make some sense of the many questions received and answered, I have tried to categorize troubleshooting air compressors into similar postings on each page. This is page one. There is a link at the bottom of the page to take you back to the forum page if you would like to offer a response or to pose a question of your own.




Starting up a compressor that hasn't been used in years?

by Dominic

Question: My air compressor hasn't been used in over 15 years. It was only used a few times when it was brand new. Is there anything I need to do to it before trying to use it after so long?

Response: Get rid of all the dust bunnies? :-) Seriously, make sure the motor is dust free. Replace the lubricating oil. Start it and monitor the operation, looking for leaks or any anomalies. If something goes awry, shut it down until whatever it is is fixed. I'd be surprised if there are any real issues, unless, of course, it has been poorly stored. Good luck. And if you have a problem, post here and we'll see if we can help fix it.

binford - for some reason the idle seems to slow and then when the pressure drops?

by Tony

Question: Binford compressor with a 5.5hp Honda Motor, the Motor will start easy, builds up pressure nicely, then when it reaches 120psi the pressure valve opens (this valve is on the side of motor and has a 1/4 hose than runs to the pop off valve on the air tank )and the Honda goes to idle.. all good you can use the compressed air then the pressure drops and the Honda revs up and builds pressure again.. it will cycle like this a number of times ,, then for some reason the idle seems to slow and then when the pressure drops and the Honda is required to rev up ,, it stalls .. it wont start again unless you apply a little pressure to the Pressure vale ,, i dont know the proper name of this valve it has the 1/4 hose from the pop valve on the air tank and the rod that comes out pushes onto the Governor lever ?? does this make scense :) oh is this valve is adjustable ?? its brass and has 2x 13/16 nuts

Response: Tony, your post is a bit challenging. :-) I don't have a copy of the Binford manual, but I pulled this from a gas powered Rolair manual...

"Every ROLAIR gas-powered air compressor is built with an engine idle control kit that automatically decreases the engine speed when the top end pressure setting of the pilot unloader valve is reached. The top RPM setting of the engine is factory set for maximum performance and service life. Do not alter the factory top RPM setting. The engine idle speed is factory set and controlled by a black plastic Philips head screw on the carburetor. A slight increase to the idle speed setting may be required when operating in colder temperatures. Turn screw clockwise in 1/4 turn increments to increase the idle speed. If the idle speed setting is too low, premature fouling of spark plug will occur." courtesy.. This might apply to your issue. I think it is an idle adjustment, and the problem is occurring when the compressor heats up.

I welcome the contributions of any other Binford air compressor owners. If OZ is down under, these guys could help:

belaire / kohler - engines shuts down?

Question: once comp reaches 150psi engines shuts down instead of going to low idle.

Response: Shawn, when it unloads, the throttle should be reduced to idle. If it moves too far, it strangles the fuel completely, and shuts down the engine, at least I suspect this is what is happening. That's no surprise to you, I guess! You need to check out the unloader and throttle control mechanism as a start. I don't work on engines and throttles. If a kind visitor does, perhaps they can comment with some help for Shawn.

Compressor pressure shuts off when peak psi is reached?

Question: My industrial grade compressor will build air pressure until the max psi is reached and will then shut off.

Response: And when it shuts off, when the pressure in the tank drops far enough, does the compressor start again? If so, that's what it is supposed to do. If not, please provide more details so I can better understand your concern.


Feb 28, 2011, by: bill j

my ridgid wheelbarrow is doing the same. mine is gas powered with honda motor on it. i took my throttle underloader apart to inspect and clean. all looked fine but there are alot of ways to adjust so it lets air in and stop at ccertin psi now in trying to figue out how to adjust


The original poster did not identify their compressors as a gass powered unit, so thanks for your input. I hope it helps him... Bill


Jul 16, 2010, by: anonymouse

You need an unloader valve (I think that's what they are called) to open when a certain pressure is reached. There are certain circumstances when you need this. What's your application for doing this?

is it ok to leave a compressor on for days at a time when not in use?

Question: i am new to air compressors and have just bought a small oil free compressor. should i empty the tank daily or is it ok to leave it with pressure in the tank when not in use? if so for how long?

Response: If you are not using the compressor for a long time, I'd empty the tank to help prevent corrosion buildup due to the water residue. If you need more info about compressor generated Water, click that link from the Nav bar. Compressors that are used for industrial application are often left on for weeks at a time. They are churning huge volumes of air too, and most (many?) will have an auto drain in their system to continuously drain the tank water. Just curious as to why you would want to leave the compressor on?

Comment: Sep 06, 2010 by: nick

bill, many thanks for your answer. i suppose i would wanted to leave it on as it so that i had the air available quickly without having to wait for the tank to charge (which is quite noisy).


Yes, compressors can be quite noisy, unless you buy one of the quiet ones. But then, most of us would have to mortgage our house to buy one of those. Cheers, Bill