Generator no longer runs well pump

I have a 5,000 Watt generator from which I have run my essentials via power cords when ever there is a power outage (once-twice per year). I have a 70 foot deep, well with a jet pump. It is normally plugged into a 110 wall outlet in the basement. There is a box with points in the basement. For some years, it ran the pump off the generator/power cord fine.

The time before the last power outage, I had difficulty getting the water pump to kick-on. After repeatedly plugging in and out of the power cord, the pump started. The last time the power went out, my generator and power cord would not start the pump, so I went to the hardware store and got the heaviest gauge 25 ft. cord they had. It still would not start the pump...* BUT* when the power came back on and I plugged the pump back into the wall outlet (118 volts), the pump started immediately.

I called the well company and told them what happened, thinking that the capacitor on the pump was going bad. They told me that "it had to be my power cord or generator...it could not be the pump."

Today, I started the generator and stuck the leads on my multimeter into the outlets on the generator. About 108 Volts each. I did the same to the wall outlet into which I plug my water pump...118 volts.

As much as my generator/25 ft. power cord has always run the pump before, why does it not do it now?

 

How many amps does the pump draw according to the name plate?

 

Could be the capacitor on the pump, but could also be the generator down on power. How is the maintenance on the engine? Clean carb, air filter, oil changes, fuel filter, etc? New clean fuel? Is the throttle set correctly and the linkage or adjustments on the speed control.

 

The pump is 70 feed down in the well casing...no way for me to know how many amps on a name plate.

 

You don't have a jet pump then...... you have a submersible pump. A jet pump stays at the top.

The box "with the points" is the starting box for the pump. It may say Meyers on it. Inside of there should be a relay and capacitor.

That must be a very small pump to run on 120v. That's rare for a submersible.

 

Yes, it is submersible, not jet.

However, nothing posted so far seems to put light on the problem.

 

As nearly as I can tell since you have no information on your well pump is that it is a 1/2hp pump and it's current draw should be around 12A. That's based on Franklin pumps avg.

Here's an interesting bit.....apparently using a generator is out according to their minimum specs.


As the pumps get older they start drawing more start up power.... especially as the bearings start to get tighter. You mentioned you tested the generator and found 108v per leg. That is WAY too low. You should have the generator readjusted to 120v minimum unloaded. I run mine at 125v unloaded.

 

How is a generator adjusted to deliver more voltage? I was under the impression that they produced a static amount.

 

I run Honda's exclusively and the engine governor is very precise and slightly adjustable.
You should be able to find the manual for yours online. See if they offer any information.

Also... do you have an Amprobe..... inductive amp measuring probe.... as that would be helpful in letting you know the amperage draw of the motor.

 

They are supposed to be roughly static, but with the exception of Honda inverters and maybe Yamaha top end unit, a 5kW portable generator is not a precision machine. There is usually just a set screw and a lock nut on the throttle assembly that has probably come loose or the linkage on the governor is gummed up or the engine is not at optimal performance. On small generators, the voltage and frequency are both tied to the engine RPM. If the engine is running too slow, both will be too low. If the governor cannot respond fast enough or if the fuel mixture at the carb is wrong or weak spark, the engine will stall instead of throttle up when the pump motor applies its start up load.