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

2 Answers

Hitachi ec12 motor hums after drop in pressue

Hitachi ec12 pumps up pressure to normal but will not restart. just hum after drop in pressure. will eventually blow breaker.

Posted by on

  • 2 more comments 
  • bobnik Feb 05, 2009

    starts real slow and sound like it wants to pop breaker.... then runs fine until next start up!

  • Anonymous Mar 21, 2009

    If there is even 20lbs of pressure in the tank, the compressor won't completely fire up. I was told there is an adjustment somewher, but can't seem to figure it out.

  • Aleksey Berezin Jul 07, 2013

    Replace start valve part #160-615 located on the engine head

  • Aleksey Berezin Jul 07, 2013

    I had a Problem with my compressor, motor hummed after drop in pressure, it wouldn't start back up. I cut of a part of the plastic cover to reach the Start Valve, when the pressure starts to build up a pin from the center hole of the start valve pops out, and by my understanding when the motor shuts off the pin is supposed to pop back in, but it didn't. So I tapped the pin with a screw driver and the pin went back in the start valve. Then I released the pressure until 80 psi (i think it depends on the adjustment) and engine started back up no problem. But i have to tap it each time for it to start like its supposed to. I ordered a new Start Valve, it should work well. .

×

2 Answers

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

I have same problem on my Hitachi EC12
It seems Start Valve (part# 160-615) need to be replaced, located on engine head, so i ordered a new Start valve
I asked about my problem with my compressor on amazon.
here is the answer i got from Amazon

A fellow customer answered your question, "how works START VALVE (160-615) on Hitachi EC12 air compressor ?" about Hitachi EC12 14.5 amp...
Edward Fitzgibbon answered
"A start valve allows the air compressor to start without a load(no-load start). It releases the compressed air from the cylinder head.This feature uses less motor amperage in the starting process of the unit. Without this feature the compressor cylinder would be under pressure and the electric motor would under this additional strain would trip the circuit breaker."
you will find Start Valve on this website
http://www.ereplacementparts.com/hitachi-ec12-portable-electric-2hp-oil-lubricated-air-compressor-parts-c-7927_13217_13219.html

Posted on Jul 07, 2013

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    MVP:

    An expert that gotĀ 5 achievements.

    Governor:

    An expert whose answer gotĀ voted for 20 times.

    Hot-Shot:

    An expert who has answered 20 questions.

  • Expert
  • 59 Answers

There should be a pressure switch adjustment under the cover of the switch remove the cover and reset.

Posted on Feb 08, 2009

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:

2 Answers

How can i fix my ec12 hitachi electric air compressor


This problem is caused by either the starter capacitor or the in-tank check valve. Ez to check. With no air in tank, start compressor; if motor hums or has difficulty suspect capacitor. If motor starts, partially fill tank and unplug the power. Check for air leaking at the pressure switch or air coming out of the air inlet (remove the air filter). If air leaking, replace check valve. If no air leaking, again let out all the from the tank and connect power. Allow the compressor to fill and shut-off. After the compressor fills, again listen for air leaking from the pressure switch unloader valve. If air continues to leak from unloader, replace the check valve. Good luck

Jun 11, 2015 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

My Hitachi EC12 builds pressure, shuts off, then air escapes


I have the same compressor with the same problem. I have temporarily eliminated the thermal reset with a piece of 12 gauge hard wire and it runs just fine. However, I do want to replace it before the warm weather come to the north. I tested the draw at 15.5 amps and the reset was a 17 amp. I am told by someone with superior electrical background that I need to install a 20 amp thermal reset in it's place. I have found that mine runs best when plugged directly into a 20 amp circuit and when using an extention cord I have a 10 guage cord that will carry the load needed to run the EC12. I have also changed to 100% synthetic oil.

May 15, 2010 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

My compressor turns on and hums for 30 secs. and then the overload protection clicks. It will not start ''compressing'' Hitachi 2 horsepower 4 gallon


Sounds like the pump is siezed or the starter capacitor has burnt out. I would try to get to the armature on the motor and see if you can turn it by hand.
If you can't turn it, remove the head of the pump to see if the valves are ok and that nothing is jamming the piston from moving ( rust, broken rings, bits of valve ).
If the piston is ok, it may be a siezed bearing.
Happy hunting

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

3 Answers

My Hitachi EC12 builds pressure, shuts off, then air escapes through the relief valve for a period of time, sometimes shorter sometimes longer. If longer, the compressor switches on again, but has trouble...


the problem is in the check valve where air enters the tank.when leaking it lets air pressure up to the air piston causing the motor to stall upon restart.replace check valve.average cost of part 15 to 30 dollars.simple fix

Mar 29, 2010 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

EC12 that fills fine, pressure switch kicks off, but then seems t


I have the same compressor with the same problem. I have temporarily eliminated the thermal reset with a piece of 12 gauge hard wire and it runs just fine. However, I do want to replace it before the warm weather come to the north. I tested the draw at 15.5 amps and the reset was a 17 amp. I am told by someone with superior electrical background that I need to install a 20 amp thermal reset in it's place. I have found that mine runs best when plugged directly into a 20 amp circuit and when using an extention cord I have a 10 guage cord that will carry the load needed to run the EC12.

Mar 15, 2010 | Hitachi EC12 Portable Electric 2hp Air...

5 Answers

I have a Hitachi compressor EC12. Sometimes when


you may have some water build up pull the cover apart look at yor pistons for build up

Jan 07, 2010 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

My EC12 has an intermitting hard start up problem. It will blow a 15 amp circut so I always make sure it is on a 20 amp circut and no extension cord. It will hum and even sputter a revolution or two but...


Single phase motors use a start capacitor and a start switch (that is internal to the motor) for start up of the motor, if either one is not working it will cause this problem, I would advise you take it to a motor repair shop to have it checked out.

Dec 16, 2009 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

My new EC12 has never run, only hums.


try an outlet closer to the electric panel I have had the outlet wire size to small and far from panel and unit only hums let me know if this helps

Feb 23, 2009 | Hitachi EC12 Portable Electric 2hp Air...

2 Answers

Ec12 hard restart after drop in air pressure


It sounds like the air pressure assembly unit is not reading the pressure drop. some of these units have adjustments under the covers and be reset.

Aug 31, 2008 | Hitachi EC12 Portable Electric 2hp Air...

1 Answer

Hitachi EC12 Compressor- weird hum


The burst of air you hear as the compressor shuts off is the cylinder unloading so it will not have to restart against a high pressure load. If the unloader is electrical it would explain the hum that you hear. This could be a normal function.

Aug 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

835 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

 Kenneth
Kenneth

Level 2 Expert

50 Answers

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

Answer questions

Manuals & User Guides

Loading...