Chinese compressor keeps turning off while running

i have a replica / knock-off yong hen compressor. In general, it is working OK except it randomly turns off while running. I have determined it is caused by the wired-in switch shown here....



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This switch seems to be flaky and keeps kicking it off. Can I simply eliminate it and replace it with a heavy duty fuse holder and fuse?


 
You need to check the full load amp draw on the compressor motor tag. Put an a clamp on amp meter on one of the wires while running to check actual amps being pulled by the motor. If you keep resetting the overload it will burn up and will trip more often. The only other thing to check is all the connections in motor circuit. If only one connection is loose it will cause high amp draw and will trip overload/ breaker. You will need to replace overload before checking for amp load on motor.
 
i have a replica / knock-off yong hen compressor. In general, it is working OK except it randomly turns off while running. I have determined it is caused by the wired-in switch shown here....







This switch seems to be flaky and keeps kicking it off. Can I simply eliminate it and replace it with a heavy duty fuse holder and fuse?


Mine was acting the same. It was randomly shutting off. It had nothing to do with temperature or load. The problem got worse over time until it rendered the compressor unusable.

I found that the relay box/board seems to be sensitive to EMI.

Rather than having it inside the case near the motor, I moved the relay box to the outside of the metal housing near the carry handle That seems to have solved the problem.

Try running it with the cover off and relay away from the motor to see if it might be a solution.

The problem was not the breaker/reset-switch. The reset-switch only trips at times when I try to start the compressor under load. When the relief valve is open, the breaker never trips.


 
I had the exact same issue when I received my Vevor compressor (thought I was buying a Yong Heng but didn't receive what I expected). The fuse would trip after 30 seconds. After checking every wire on switch and motor for bad connections, shorts, and not finding anything...I had a hunch the fuse itself night be faulty. I've read other people's experience with all models of Chinese compressors over the past 6 months and found that it's well within possibility to have poor quality electronic components in these compressors that don't perform anywhere near the rated spec that's printed on the part (relay, switch, and in my case fuse).

To fix my issue, I bought a higher quality fuse and replaced the one that shipped with the compressor. The fuse used in the compressor is a 125VAC/15A fuse and I changed it out with a NTE branded fuse with the same rating. NTE is a reputable manufacture of components. You can buy one from Amazon here:

https://www.amazon.com/dp/B002SR1U02/ref=cm_sw_r_cp_apa_NpdqBbHMV1ZEP

Installation is straight forward with no modifications needed. The factory wire connectors plug in to the NTE fuse, and it's mounted the exact same as the factory fuse. If the suggestions other people have you don't pan out, consider swapping the fuse like I did...but don't hotwire it and bypass the fuse completely. It's not advisable to f**k around when you're dealing with mains power at 110v.
 
I also had electrical problems with my second Yong Heng. It was stuttering or missing due to a bad relay. I first mounted it in foam, as I thought it was getting too much vibration; that helped a bit but didn't cure it completely, so I just removed it along with the red light and auto-shut-off and wired the motor direct to the switch. That seemed to work, but now I need to stand there for an hour or more while my tank fills, so I can keep an eye on the pressure. The only problem I still have is the cylinder head overheats.....even with ice in the cooling water, it still hits over 65 degrees C. Probably the high ambient temps here, (118F outside the shop yesterday). Other annoyances are it takes about 5 minutes just to pressurize the air dryer, before you can start filling the gun or bottle, due to it's large volume. I should install shut-off valves before and after the dryer, so I can bleed the compressor and tank lines, without draining the dryer, but I doubt that it seals well enough to maintain pressure over the weeks between uses. These are things you can expect to deal with when you cheap-out on your compressor choice. 
 
I replaced the 110v wall plug with 12 awg wire to a MOTOR RATED 15 amp switch and connected the motor wires to the switch in a box mounted to the chassis. I've also been informed a few times to input the water to the bottom of the cylinder. I now have to plug the water pump seperately to a wall plug but it's cool with that ❄️Bill. The temperature guage is reflective of the compressor piston not the electric motor.
 
I realize that the temp gauge/meter reads the cylinder head temp, not the electric motor , but you make a good point for other YH owners. High ambient temps will still affect the temp reading to a small extent, aside form melting the ice in the bucket quicker. The cylinder and heads are at least partially cooled by the surrounding air. I think the next time I have the second stage apart, I will try to port the water jacket passages and/or increase the pump capacity/pressure with a better water pump to compensate for my miserable local air temps.