Hitachi Air Tools & Compressors - Page 4 - Recent Questions, Troubleshooting & Support

Does compressor have oil in reservoir? If not, add oil. Also the switch may have gone bad.

The allen screw/s that you mention are there to plug holes where automatic equipment would normally connect (such as automatic nailing machines) . This is only a plug and should not be driven in too far. I have also seen allen screws installed in the head to repair small crack/s.

What model tool is it? -Jeff

oil it all the time

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.

If your using refills that have wire holding the nails together. Check to see if bits of wire, debris is collecting in around the striking hammer. I switched to paper and never looked back. Must have gone through 5k worth of nails and rarely jams. Other things to check, 1. Check the striking hammer, make sure it is not bent or damaged. 2. Check air pressure, Low pressure can cause jamming, misfires. 3. If the tool needs pneumatic oil, 2-3 drops before you start good rule of thumb. 4. Check spring return. Sufficient pressure must be maintained or the nails will not feed properly. Misfires, incorrect feed, jamming etc. I had a Hitachi brad nailer and it was horrible. Fire 1 brad nail would jam or misfire. Did everything I could think of nothing worked. Put it up, got a Rigid brad nailer and never looked at the Hitachi again. :) Sometimes you just get a lemon! (PS I understand you have a framing nail gun. Brad nail gun above is used for an example) Hope this helps

Several things to check. Check amp draw with meter to make sure that the reset is not bad. It amp meter is showing low amp draw when it trips, then replace reset. If reset is good check condition of the cold start valve. The valve will not allow pressure to build until motor is at full rpm and the pump is making good pressure/volume. If cold start valve does not close, check pump for leaking or broken reed valves. If cold start valve is good, check the capacitor for at least 10 percent of rated valve. Low pressure /volume is usually leaks from tubing or leaking /broken reed valves or burned gaskets in the head of the pump. Finally, make sure that the check valve or non-return valve is not leaking pressure from the tank causing back pressure. Good luck

really depends on the model of compressor but if it is an oil less compressor best thing is to junk it and buy a oil lubricated with a cast iron pump dont get one with aluminum if you want a compressor to last you for many years.