Harbor Freight Predator 3500 Generator Review and Fuel Use

[d_dubya]

Hi everyone. I just finished my first round of testing my new Predator 3500 inverter generator. I bought this to replace my Honda eu2000i. The Honda would push the 9000 BTU AC in my Lance trailer, but it was near top volume and felt like it was running flat out. I wanted an EU3000i, but didn't have the cash. Figuring I would get an extra 2 years warranty if I used my Costco Visa, the risk was low so I took the plunge.

Using my calibrated ear gauge, I think that noise is equal for all practical purposes. The Honda is slightly quieter with no load in eco-throttle, but the Predator is much quieter under loads of 500-1500 watts. The predator never feels like its running at the limit like the Honda does.

My biggest curiosity was fuel use and whether the Predator would live up to the claims on the box: 11 hours at 25% load (750 watts), and 90 hours at 50% load (1500 watts). I tested this by measuring out 250 ml of fuel, running under a constant load until the generator died. I did this for a few different loads generated using a heat gun and my wife's hair dryer. Ecotyhrottle was on for all cases. Here is what I found:

@ zero watts, runtime was 32 minutes (21 hours/tank)
@ 356 watts, runtime was 22 minutes (14.4 hours/tank)
@ 947 watts, runtime was 17 minutes (11.2 hours/tank)
@ 1647 watts, runtime was 12 minutes (7.9 hours/tank)
@ 1996 watts, runtime was 10 minutes (6.6 hours/tank)

Based on this data, I plotted a trendline in Excel and calculated the expected results at 25% & 50% load. They were 11.9 hours and 8.7 hours. This exceeds the published value at 25% load, and is slightly below at 50%. I would say that this is a very good result.

Comparing this to published data from the Honda shows that @ 400 watts (25% of the Honda rated load), the Honda uses about 37% less fuel at 400 watts and about 17% less at 1600 watts.

Overall I am very happy I made the switch. I can run my AC, microwave, water pumo and all of my lights at the same time. Time will tell on reliability but it feels very solid and runs really smooth.

[Range_Maggot_Bo]

Using my calibrated ear gauge, I think that noise is equal for all practical purposes. The Honda is slightly quieter with no load in eco-throttle, but the Predator is much quieter under loads of 500-1500 watts. The predator never feels like its running at the limit like the Honda does.


Well duhhh! I think you're talking two different size gennys here, correct?

[pnichols]

MrWizard wrote:
i have never seen 10FT as a standard on any generator

i would not mine having a 'new' distance added to standard testing list

but i have never seen it used by any mfg or advertiser

The article in my link seems to "suggest" that maybe 10 feet, along with 23 feet and 50 feet, are part of some standard somewhere - but I haven't dug into govt. standards to confirm it one way or the other.

It seems strange that Onan has used 10 ft. (3m) for years in the noise specifications for at least their smaller generators for RVs ... I assume they had/have a reason for using 10 feet. Check this typical RV Onan generator's specifications - at the top on the right: https://powersuite.cummins.com/PS5/PS5Content/SiteContent/en/Binary_Asset/pdf/Consumer/specsheets/a-...

[SaltiDawg]

d_dubya wrote:
Hi everyone. I just finished my first round of testing my new Predator 3500 inverter generator....

My biggest curiosity was fuel use and whether the Predator would live up to the claims on the box: 11 hours at 25% load (750 watts), and 90 hours at 50% load (1500 watts). ...

I tried by private message to contact d_dubya to point out the typo/error. That would be 9.0 not 90 hours at 50%.

[TomG2]

pnichols wrote:
If one reads the link I provided, it's there in print what both the idle and full load noise specs are for an Onan and the Honda 3000 at all 3 distances - 10', 23', and 50'

I was merely mentioning that it would have been great to see how quiet the Predator 3500 would have been at the closest standard of 10 feet.

It's no more complicated than that.

I followed, read, and quoted directly from the link you provided. The point is that anyone who takes published Honda ratings (at 23') and compares them with the 10' measurements you suggested, they will find out that the 10' readings will be higher. Surprise surprise.

"It's no more complicated than that".

(I am not saying that the Harbor Freight unit is better than or comparable in any way to the Honda 3000 watt inverter generator, just that comparisons need to be fair)

[MrWizard]

i have never seen 10FT as a standard on any generator

i would not mine having a 'new' distance added to standard testing list

but i have never seen it used by any mfg or advertiser

[pnichols]

If one reads the link I provided, it's there in print what both the idle and full load noise specs are for an Onan and the Honda 3000 at all 3 distances - 10', 23', and 50'

I was merely mentioning that it would have been great to see how quiet the Predator 3500 would have been at the closest standard of 10 feet.

It's no more complicated than that.

[TomG2]

pnichols wrote:

Here's an informative article that mentions 10 feet as one of the measurement distances used for comparing generator noise: http://klenger.powweb.com/RV_General/Electrical_Generator_Noise/index.html

From your "informative" article, "67 db @ 23' (Honda specs are at 23')"

23' would be significantly different from 10'. Apples and oranges when it comes to comparing published noise ratings to those of another generator measured at 10'. Why not simply use 23' for both? Wouldn't that be the fair comparison that we are looking for? Or do we want a fair comparison?

[pnichols]

pnichols wrote:
Now ... if only we had 10 foot distance dB (A) noise data at the 5 power levels you used for fuel consumption testing ... we'd be all set to make a solid comparison to the other red and black generator.

TomG2 wrote:
Most red and blue generators are noise rated at 7 meters or approximately 21 feet which would give them a nice advantage compared to the 10 foot distance proposed for this test. Solid comparison?

I picked 10 feet on purpose because I've seen this distance referenced several times with respect to how irritating generator noise may or may not be to the generator operator or fellow drycampers - either of whom might be close to the running generator.

Here's an informative article that mentions 10 feet as one of the measurement distances used for comparing generator noise: http://klenger.powweb.com/RV_General/Electrical_Generator_Noise/index.html

[TomG2]

pnichols wrote:
Now ... if only we had 10 foot distance dB (A) noise data at the 5 power levels you used for fuel consumption testing ... we'd be all set to make a solid comparison to the other red and black generator.

Most red and blue generators are noise rated at 7 meters or approximately 21 feet which would give them a nice advantage compared to the 10 foot distance proposed for this test. Solid comparison?

[RSD559]

If the Predator is like my Champion, it uses gravity to feed the carburetor. So as soon as you put gas in, you primed it for the fast start. I don't know if it has a fuel pump or uses gravity. Just a possibility.
And if it does use gravity, like my Champion, you can use the procedure from this forum to add an external tank, if you would like.

[pnichols]

Now ... if only we had 10 foot distance dB (A) noise data at the 5 power levels you used for fuel consumption testing ... we'd be all set to make a solid comparison to the other red and black generator.

By the way, it seems like larger wheels would make it easier to shove around on gravel or dirt surfaces.

[Dave_H_M]

I just bought one of the predator motors for a replacement on my garden tiller.

:h I sniffed the tank wondering if it ever had fuel in it. Smelled nothing. however it started on the first pull right out of the box also.

I also have the open frame Predator for back up power for the house, but hopefully it will never have to work for a living.

I also have no complaints on my champ inverter which I bought before the predators really came into being.

Now i regret not getting the 3100 inverter right out of the chute. Like you did, I would have the power with one unit. I scoff at the weight since I have a manual cherry picker (engine hoist) and a front loader for the lifting and it would stay put in the pick up bed.

[kerrlakeRoo]

Congrats, you got the $1,000 oil change out of the way, hehehe
The guys riding Chinese bikes and scooters called it that, they were my source for starting that practise and my old dirt/mini bikes did well that way.

[DennisVR]

I'm pushing 400hrs on mine and really like it.