Do you have the Harbor Freight 15KW PTO Generator? What do you think?

[DarkBlack]

One of the big problems in running gasoline or diesel portable gens is not giving them enough load. After installing a 20kw Generac stand by unit on my home, I loaned my 5kw portable unit to a friend. Got it back a year later fresh out of the shop having had the cylinder and head cleaned of excess carbon. Guess I should have told him to put a space heater on it if running light, which is what I do when I use my portable on the farm. I don't worry about carbon with the Generac since it's LP powered, and obviously running a gas or diesel tractor at pto rpm isn't going to be an issue other than fuel consumption. Most of the times we lose power is in bad weather, perhaps like most, and
leaving a tractor running outside unattended would worry me too much.

Why would a modern portable gas generator running unleaded fuel, develop a troublesome head carbon build-up during a light load? An oil burning worn engine..yes.
And you say it isn't an issue with a gas engine tractor? I've never heard of such a thing.

 

[DarkBlack]

I decided to run the PTO generator today while I cut the grass. I isolated the garage and turned the garage and upstairs lights, 1500 watt heater, drill press, fan, belt sander, and grinder. Totaling 3.45KW. I ran this for 4 hours exactly and the tractor used 4.1 gallons of diesel. The load was unbalanced with and here are the details:
Volts- L1-ground- 117V
Volts- L2-ground- 124V
Volts- L1-L2- 241V

Amps L1-27.5A
Amps L2-4A

Watts 3.45KW

I was surprised at how ineffiecient it was on fuel. It could have been because of the imbalance of the loads or that it was lightly loaded. I will likely do the same test with a larger load that is balanced.

After I finished I changed the gear box oil. I took the drain plug out and it was under great pressure for a gear box. I checked the breather and it has a spring loaded ball check. I pulled the spring and it was very stiff. I deemed it too stiff and replaced it with a much shorter and less stiif spring. I didnt see much in the break in oil except a few fines from the gears meshing. Voltage was stable and the frequency was rock solid.

Dex, An interesting test "in the name of science" would be if you ran the tractor with all the same conditions, with the exception being that you have the generator pto shaft disconnected. That will let you see how much of the total fuel is being used, just to spin the tractor pto stub at that speed.

 

[daugen]

I learned this with my boat generator, being told early not to run at light loads. Diesels of course need to get hot to be efficient, and apparently low load situations created a variety of problems.
I'm not exactly sure why gas engines do this, but over time, this is a recognized problem, and the repair shop my gen was fixed at said they see this all the time. I'm not making this up...
Not sure if ethanol is a factor here, but carbon builds up on the head, the piston top and the valves/valve seats and in my case, the engine would no longer start. Hopefully someone else can chime in here with a better
answer.

 

[dex3361]

I learned this with my boat generator, being told early not to run at light loads. Diesels of course need to get hot to be efficient, and apparently low load situations created a variety of problems.
I'm not exactly sure why gas engines do this, but over time, this is a recognized problem, and the repair shop my gen was fixed at said they see this all the time. I'm not making this up...
Not sure if ethanol is a factor here, but carbon builds up on the head, the piston top and the valves/valve seats and in my case, the engine would no longer start. Hopefully someone else can chime in here with a better
answer.

Absolutely a problem to run a diesel with no load for long periods of time without getting it good and hot from load to clean out the cylinders. The condition is know as wet stacking. The diesel fuel does not completely burn under light loads.

 

[dex3361]

Dex, An interesting test "in the name of science" would be if you ran the tractor with all the same conditions, with the exception being that you have the generator pto shaft disconnected. That will let you see how much of the total fuel is being used, just to spin the tractor pto stub at that speed.

Thought about doing that and it would give a baseline of what it takes to run the engine and PTO gearset.

 

[bubbacuse77]

Looking at Rural Kings web site, they say in the question and answer section that it is brushless.
I would just like to know what it is, brush or brushless?

 

[bubbacuse77]

Looking at Rural Kings web site, they say in the question and answer section that it is brushless.
I would just like to know what it is, brush or brushless?

 

[dex3361]

It looks just like the generator that is on my HF unit. My HF generator has brushes. I cannot say for sure about the Rural King generator though as I have never seen one up close.

 

[SPYDERLK]

I decided to run the PTO generator today while I cut the grass. I isolated the garage and turned the garage and upstairs lights, 1500 watt heater, drill press, fan, belt sander, and grinder. Totaling 3.45KW. I ran this for 4 hours exactly and the tractor used 4.1 gallons of diesel. The load was unbalanced with and here are the details:
Volts- L1-ground- 117V
Volts- L2-ground- 124V
Volts- L1-L2- 241V

Amps L1-27.5A
Amps L2-4A

Watts 3.45KW

I was surprised at how ineffiecient it was on fuel. It could have been because of the imbalance of the loads or that it was lightly loaded. I will likely do the same test with a larger load that is balanced.

After I finished I changed the gear box oil. I took the drain plug out and it was under great pressure for a gear box. I checked the breather and it has a spring loaded ball check. I pulled the spring and it was very stiff. I deemed it too stiff and replaced it with a much shorter and less stiif spring. I didnt see much in the break in oil except a few fines from the gears meshing. Voltage was stable and the frequency was rock solid.

I suspect the majority of the time I will use the PTO generator on the BX1500 as the 10 PTO HP of the BX will crank out likely 5KW - 6.5KW but that is normally more than I will need. I will need to use the L4400 when its summer and I need the AC or anytime I need more KWs. I expected it to be less effiecient than a direct to engine coupled but that was worse than I expected. Being unbalanced and at the low end of the HP of the tractor 37PTO available but only +-6HP being used. That put it out of the effiecient range. Also going through several gearboxes eat up some eat away at the effieciency.

Also I used a true watt meter to check the watts in case anybody was wondering it was not calculated.

Yeah, thats what I thot. Using the big tractor at lo load. I use 1gph using the BX1500 to drive my 12KW at ~7KW output. BX is fully tapped out with that load.
larry