Troubleshooting Compressors Two

This wesite has receiving hundres of questions about troubleshooting 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 two.

And, if you see a post below to which you would like to make a suggestion or ask another question, the forum page is linked from the bottom of this page.

Cheers & thanks. We all appreciate your help.



Building my own compressor?

Question: hey im building my own compressor to my standards at a descent price and im rigging this up with a 6.5 horsepower briggs and stratton vanguard motor and a compressor im going to buy off of ebay or wherever i can get it at. what switches do i need and what do i need to control the idle on the briggs 6.5 ?? is this something i need to find already built into my motor or can i add a pressure controled idle switch onto my briggs motor?? and where do i find such a thing??

Response: Andrew, good on you. Maybe you could post again with photos when your baby is built.

The Briggs & Stratton motor will need to idle down when the tank is full, or the air demand is met. Unlike many electric compressor motors, gas and diesel don't shut off when they unload, they just slow right down. I don't know if your motor will come with it.

Some folks that you might want to talk to are:

Compressor motor quit after getting wet - why?

Question: Why did my running motor(120v/60HZ) quit working after being ran in the sprinkling rain for just a few minutes. i HAVE A HUSKY 100 max psi air compressor that is practically brand new. it has only been used a matter of just a few it has left me with a question of why?

Response: G'day Dave. and thanks for writing in. While it's hard to determine how wet a compressor will get after it "ran in the sprinkling rain for just a few minutes", wet it did get. Wet enough, I'd guess to short something out. Once your motor is completely dry, try starting the compressor again. If it still fails to start, check the pressure switch and make sure it is working. Check the motor and see if there is a reset button. All else fails, check the Repair page to see who near you fixes compressors, or ask the store where you bought it where you can take it to get it looked at. Cheers and good luck.

Can I replace a single stage air compressor pump with a two stage?


Response: Sure, you can replace the pump with any size and number of cylinders you like. The air tank into which you are pumping air doesn't care, as long as the pressures are comparable. However, you need to check the specifications on the new pump to be sure that the HP of your existing motor will suit. No way I can tell you that from this end. I suspect it will, but you need to be sure to save you from doing a lot of work needlessly. Where is the pump coming from? They should be able to tell you the optimal motor HP.

Calculating the losses in an air compressor?

Question: I want to know the losses in KWH of a compressor having on load time 5.43 min, OFF load time 6.66 min. Compressor receiver volume is 2.83 m3. Pressure reached in the vessel is 6.9 kg/cm2. The rated KW of the compressor is 132 KW. Capacity of the compressor is 845 CFM I want to know the losses in KWH. So please help me in solving this problem.

Response: Hi Nishit... I'd love to help, but the request is way beyond my capabilities, and really, of my interest. I'm more a hands on guy. Why not contact your compressor manufacturer who, I'm sure, has already done all these calculations? Or, let's through ourselves on the knowledge of the visitors to this site. Can anyone provide any response to the question?

Calculate air required for transporting material?


  • material to transport is fly ash
  • conveying distance is 800 m
  • quantity 140 TPH

Response: Hi Vicki. Good questions. The design build of an air vacuum or air transport system is beyond the scope of this website. However, you should contact two companies that come to mind. One is, and the other is You should be able to get your needs addressed by one of them.

(How expensive and what is the )Energy usage from compressed air supply?

Question: Hi Bill, I have compressed air lines and a flow meter to measure the flow rate (m3/hr)of compressed air to various machines, but, if I want to relate that back to watts (energy) used by this flow rate, is it the pressure difference across the machine that i multiply by? :

watts = flow rate * pressure drop?

Many thanks & thank you for your time Aaron

Response: Aaron, wouldn't it be easier just to monitor the running of the air compressor? Knowing what it costs your air compressor to run, and knowing the theoretical output in CFM, would accomplish what you want, I would think. Pop over the to the site map, scroll down to costing a compressor, and visit this page. I would think that all you are looking for could be found there. Compressed air energy is among the most expensive energy forms there are, in that, you are using expensive energy (electricity normally) and converting electrical into stored energy in the form of compressed air.

Comment: Nov 05, 2010 - by: Aaron

Hi Bill, thank you very much for your reply, and the useful links. Perhaps i should explain more fully: The overall project is one of carbon footprinting. As a number of compressors are connected to a main line which branches off to feed individual machines, the measurements must be taken at the actual machines (the compressed air users) as that is what is required for the calculations. So, flowmeters are can be installed at the lines to the machines, but it is the energy in compressed air used (Watts)(on a per machine basis) that is required. The compressor efficiency figure itself can then be used to calculate the electrical watts used for the compressed air supply to the machine in question...if that makes sense...? Many thanks once again Bill, Aaron


Hello again Aaron... I must confess that you've moved outside of my realm of any expertise, though I certainly applaud the concept of determining the carbon footprint of compressed air consuming machines. Perhaps I could ask the many visitors to this site to offer suggestions to Aaron? Cheers and thanks, Bill