Question about Hitachi EC12 Portable Electric 2hp Air Compressor, Oil Lubricated

4 Answers

My compressor is a Hitachi EC 12. It has a brass fitting ( ? check Valve?) where nylon air line from air tank inserts into the presure switch (EC10SC) shown as "B" on parts diagram. This fitting constantly leaks air out of a small hole on the side of the fitting where it is recessed into the back of pressure switch at "B" and secured to the pressure switch via a small hex key. This brass fitting is 1 25/32 inches long. Is this a check valve? Can you tell me exactly what it is? Do you know the part number to replace it?

Posted by on

  • 4 more comments 
  • drbill47 Sep 11, 2010

    Thank you for your answer. I already have the parts diagram and the parts list for the Hitachi Air Compressor EC 12. I need a specific answer to my question.
    The brass part is not shown on the parts diagram or listed on the parts list.
    After research on the internet, and review of many websites, I believe that this part may be a Pressure Check Valve. Again, not shown on the parts diagram nor listed on the parts list.
    This brass part is 1 25/32 in. in length by 1/2 in. in diameter, and has a machined groove on the end that inserts/attaches into the pressure switch(EC 10 SC) at the place shown as "B" on the parts diagram, and is secured in place by a 2.5mm hex screw. The nylon hose is secured into the end of this brass part and the other end of the nylon hose attaches to the non-return valve.
    This brass part inserts into the pressure switch BELOW fitting number 63 on the parts diagram at the place labeled "B".
    Can someone please help me with this? Please do not refer me to another diagram, or list, unless it shows and lists the name and part number that I am asking about.

  • drbill47 Sep 11, 2010

    My compressor is a Hitachi EC 12. It has a brass fitting ( ? check Valve?) where nylon air line from air tank inserts into the presure switch (EC10SC) shown as "B" on parts diagram. This fitting constantly leaks air out of a small hole on the side of the fitting where it is recessed into the back of pressure switch at "B" and secured to the pressure switch via a small hex key. This brass fitting is 1 25/32 inches long. Is this a check valve? Can you tell me exactly what it is? Do you know the part number to replace it?
    The last "expert" referred me to parts diagrams on two different websites. As I have said, this part does not show on the parts diagram, and is not listed in the parts list. But I assure you that it does exist, and it is the cause of my compressor malfunction. Please help me.

  • drbill47 Sep 12, 2010

    The brass part that connects the air line to the pressure switch is the part that is leaking .The unloader switch is at the tank. This brass fitting(part?) is at the other end of the air line. Connecting the air line to the pressure/on off switch. This is where the air is coming from. How can the unloaderswitch coming from the tank be bad if the air leak is at the other end of the nylon air line? Do you know what this fitting that connects the nylon air line to the pressure switch is called, and what it's function is? Why is this fitting leaking air if the unloader switch is bad? It makes no sense to me. I am not an expert, but I am a logical and methodical person. Could you please explain thi to me? Thank You!

  • drbill47 Sep 14, 2010

    Thank you very much for your patience and your detail.

    Sorry about your personal loss. I'll say a prayer.

    I will order a non return valve, install it, and go from there.

    I will let you know the results.

    Thank you again.

    DrBill47

  • drbill47 Sep 29, 2010

    I have replaced the switch including the check valve with an identical new part. I have also replaced the non-return valve with a new replacement part.
    when I turn the compressor on, everything works, but the air leak at the end of the new check valve where it inserts into the switch remains unchanged.
    I believe that I have replaced all of the parts from the tank to the regulator valve, to no avail. I have even tried another regulator valve, but of course it made no difference.
    Is it possible that I received a bad check valve with my switch?
    What else could cause this problem? A bad replacement part?
    I am very frustrated. Could you please help me with my problem?
    I have tried everything that you, and the "experts" before you have recommended.
    What next?
    Thanks,
    DrBill47

  • drbill47 Oct 11, 2010

    I replaced the switch, check valve, and non-return valve with new parts. The problem persists, unchanged.
    DrBill47

×

4 Answers

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 2 Answers

Tryed the methed john trevino spoke about I pulled the non-return valve off cleaned it still the same pull it out again took some sand paper sanded the plug reinstaled non-return valve works like new thanks for the info john saved me from taking compressor to the shop

Posted on Jan 10, 2012

  • Level 1:

    An expert who has achieved level 1.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 8 Answers

Youor problem is actually the unloader valve. Your pressure switch is an older style Condor MDR21 (http://www.google.com/imgres?q=condor+mdr21+pressure+switch&hl=en&biw=1244&bih=739&tbm=isch&tbnid=SpfaC0uYVDGONM:&imgrefurl=http://www.bettervac.com/hitachi-881575-pressure-switch-condor-mdr-21.asp&docid=QTBY4coa024BpM&w=242&h=242&ei=qi2PTsbDKZCutwe2vMGsDA&zoom=1). The check valve is connected directly to the tank and the feeder line for the unloader connects to it, as well as the main line from the compressor pump. doing a little research on google you should be able to find one for less than 20 dollars. Or you can replace/upgrade your pressure switch to a newer model, which is shown in most of the manuals and parts break downs. Yours is probably the pre 2005 model. If you still need more assistance please repost with additional questions.
Tim

Posted on Oct 07, 2011

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    President:

    An expert whose answer got voted for 500 times.

  • Hitachi Master
  • 1,383 Answers

The most common problem with ec12 compressor is the non return valve part # 881-581 (check valve). The purpose of this valve is to hold pressure in tank. When the valve begins to leak, the air will be discharged thu unloader valve at the pressure switch. Simple repair, order valve from www.toolpartsdirect.com or you can use generic valve from www.grainger.com Good luck and post again if you have other question.

Posted on Sep 11, 2010

  • John Trevino Sep 13, 2010

    Sorry about the delay, had death in family. Refrence #53 is the check valve, its purpose is to keep compressed air in the tank. If it leaks the air will come out of the unloader which is built-in to the pressure switch ref. #63. The unloader valve/stem works like valve stem in bicycle tube. The unloader is not a replaceable part (generally not sold seperately because it hardly ever fails before the whole pressure switch fails) This link will show you a generic switch that I use for replacement instead of factory part http://www.northerntool.com/shop/tools/p.... In the photos you will notice the unloader connection that is referenced as connection (B). If you feel that your unloader stem is bad then you will need to replace the whole switch unless you find a used part at local repair center. So to answer this question; ( It has a brass fitting ( ? check Valve?) where nylon air line from air tank inserts into the presure switch) this is unloader built in to pressure switch.

    Most ec12 compressors suffer from leaking check valve, easy to check remove large tubing and spray soapy water, it is leaking, replace it and problem solved, good luck

×

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Master
  • 10,865 Answers

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

My HUSKY air compressor mod # WL651004AJ,will startup but after it reach 150psi,the presure will drop and it will not startup again.


This problem is usually caused by the in-tank check valve. Follow the discharge airline from the pump to the tank. This line will connect to a brass or chrome valve (check valve). Easy to test. With air in the tank, pull power cord for safety, remove the small tube (or larger) at the brass valve. If air is leaking here, replace the valve with generic valve or try removing the valve and clean the seat. Good luck.

Dec 04, 2014 | Air Tools & Compressors

1 Answer

I have an old 5hp 20 gallon horizontal Craftsman air compressor that is well over 20 years old. The on off presure switch died so I replaced it with a Powermate unit of the same on - off pressure...


possibly an installation problem
most control units screw directly into the tank and the pressure is read directly to the diaphragm that controls the switching
check if the bleeder line is supposed to be attached to the control unit at all
unless you have a peculiar set up the compressor line goes to a nonreturn valve into the tank
there is a relief valve in the tank that blows off when dangerous pressures are reached ( around 120 psi)
there is a fitting where the control screws in and that reads tank pressure to control the on/off of the motor

Apr 17, 2017 | Craftsman Air Tools & Compressors

1 Answer

I have a air compressure with a square d 9013fhg44mix pressure switch. The problem is where the 1/4 air line goes, this valve leaks when ever the compressor is off. Once the compress is on it is off and...


The 1/4" line is very necessary and there are no adjustments on it. When the tank reaches full the pressure switch turns off the power and opens the valve to the 1/4" line to bleed off pressure from the air pump and feed tube so the motor can turn over the next time the tank drops to the kick in pressure. Every time the pressure switch turns the motor off a small amount of air should be heard coming out of the bottom of the switch for three to five seconds and then it should stop completely. If air continues to leak out of the switch by the 1/4" line, you have a bad tank check valve. The tank check valve is the brass fitting at the other end of the 1/4" line where the feed tube from the air pump goes into the tank. It keeps air in the tank after the pressure switch turns off the motor. Easy to replace, find the one you need for your model compressor.

Mar 25, 2011 | Square D 9013FHG14J52M1X Air Compressor...

1 Answer

Compressor pumps up fine but then leaks air just below the relief valve. out of a small factory hole in a brass fittting and goe down till compressor starts again.


When the unloader leaks as you describe indicates that the check valve is leaking. Easy to check the condition of the valve. Follow air discharge line from compressor head to tank. The brass or steel fitting that threads into tank is the checkvalve. Remove all air from tank and remove large inspection cap to reveal the teflon seat. If it is cracked or swollen you will need to replace the valve. Parts available at www.toolpartsdirect.com Good luck

Sep 25, 2010 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

After my Hitachi ec12 compressor pumps to maximum pressure it shuts off and immediately starts dumping air out of the part name "Joint" which is item 60 in the parts list. It will dump until the motor...


The problem that you describe is most likely the in-tank check valve (brass or chrome valve where air enters tank ). Easy to check. Run compressor till you have about 60-80 lbs in tank then shut-off / unplug for safety. Remove the small hose (1/4) at the check valve and verify that air is leaking from valve. If leaking remove cap from checkvalve and look at inner plastic valve for cracks. Replace as needed then re-test for leaks. You can be creative in making the inner plastic valve (teflon or nylon ball 1/2 - 5/8 ) or replace the whole valve. (inner part not sold separately) Good luck with your repair and post again if you have a question.

Jun 24, 2010 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

Hitachi EC 12 Air Compressor does not keep pressure


to repair this problem (a) the pressure switch is not working,(b) check valve or non return valve sticking(stripe down repair and refit)

Sep 28, 2009 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

Coleman Powermate Model Number BV6548049, pressure switch leak.


Usually, a leak at the pressure switch unloader valve is caused by the checkvalve in the tank. The unloader valve at the pressure switch bleeds out the air from discharge tube after compressor reaches set pressure. This only takes a few seconds. If air continues to leak then air is leaking back into the discharge tube past the tank checkvalve. Follow the air discharge line from the compressor to the brass valve at the tank. The brass valve is the checkvalve that holds the pressure in the tank. There are usually two connections at this valve. One is the unloader tube to the pressure switch. Simple test for leaking checkvalve, with pressure in tank unplug or switch off the compressor and remove the small unloader line at the checkvalve(brass valve) and look/listen for leak. If leaking, remove the checkvalve and examine seat/check for debris keeping the valve slightly open. If it cannot be cleaned, order generic replacement from www.grainger.com. It will cost less than the factory checkvalve. Just pay attention to the thread sizes for easy fit. Good Luck on your repair and email if you have questions.

Mar 25, 2009 | Coleman Powermate 60 Gallon Air Compressor

1 Answer

AIR LEAK ON CRAFTSMAN AIR COMPRESSOR, 3HP,25 GAL, HORIZ TANK


The needle valve that you see is the unloader which releases air pressure from the discharge line after set pressure is obtained. If air continues to leak after the compressor shuts off, the check valve installed in the tank is leaking air out of the tank. Follow the air discharge line from the compressor to the tank. There you will find a brass valve which is the check valve. Simple test is to remove the smaller airline (1/4") from the brass valve and check for air leaking. If leaking remove brass valve and check for debris under the white seat. If you cannot clean the valve, replace with generic check valve from www.grainger.com. It will cost less than factory part. Just order the valve considering the fitting sizes that you need. For exact replacement,( www.sears.com parts). If you sears model # begins with WL then your compressor is made by campbell hausfeld and parts may be ordered from www.chpower.com. Good Luck with you repair and email if you have more questions.

Mar 21, 2009 | Craftsman Air Tools & Compressors

1 Answer

Air compressor problem


Cheap oil-less compressor, normal.
If you don't like it, buy one that uses oil and a drive belt.

Sep 24, 2008 | Hitachi EC12 Portable Electric 2hp Air...

Not finding what you are looking for?
Hitachi EC12 Portable Electric 2hp Air Compressor, Oil Lubricated Logo

972 people viewed this question

Ask a Question

Usually answered in minutes!

Top Hitachi Air Tools & Compressors Experts

John Trevino

Level 3 Expert

1383 Answers

Jim Thurston

Level 3 Expert

670 Answers

Doctor PC
Doctor PC

Level 3 Expert

7733 Answers

Are you a Hitachi Air Tool and Compressor Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...