Short Lifespan of Harbor Freight 800 watt Generators

[dragonflyspit]

I'm wondering if someone knows why these cheap little generators put out fewer and fewer watts over their little 100 to 150 hour lifespans.

I've run through about ten of them. Every one of them has been different from the last. No two have ever sounded alike, started alike, etc. It's as though each one is made individually instead of by mass production. A couple have failed in other ways, but the one thing they all have in common is that over a month, they slowly produce less and less power until they won't even charge the batteries.

Each lasts only about a month of running about 4 hours per day. I follow all the rules for breaking in period for each one; I've never overloaded one; I use the right gas/oil mixture, etc.. I've tried replacing the spark plug as as soon as I replace one, and I've tried replacing it every few days. I've done nothing wrong, but nothing extends their life.

What do you suppose goes wrong with them?

(I'm not looking for advice about what generator to buy, etc. I'm just curious why these particular generators fail in this way.)

[LittleBill]

bump

keep this alive i want to hear the outcome

[beemerphile1]

I don't run my little 800/900 regularly but it works okay after having for several years.

How are you measuring output? Mine will put out 900-1000 watts regularly.

I have found that it is a little erratic. I have the output voltage at 130+ unloaded in order to have 115-120 under load. It is adjusted by an easily accessible screw.

If you read the reviews on the HF website they are mostly positive. It seems that most people have the opposite experience you are having. Many are bad to begin with but once you get a good one they run. I had to return the first one I got because it had been dropped and damaged before placing in a flawless box.

My only real complaint is that it is hard to start and has always been hard to start. It takes 10-15 or more pulls when cold. I've changed plugs and made adjustments without improvement on the starting.

[Mont_G_J]

Quote dragonflyspit
"Evidence it's not putting out the same power? Less power to my 120 volt appliances - my blender slows; my box fan slows, and it stops charging my batteries worth a damn. The generator gets quieter toward the end of its life too, and eventually it won't even power my little TV"

As a long time Small Engine Repairman, if you brought one of these in for repair, I'd have you wait around for about ten minutes while I cleaned the Spark Arrestor screen located inside the exhaust muffler. Spark arrestors are required by the U.S. Forrest Service and when they start to carbon-up the unit starts to lose power and become quieter until it quits.
If you're not running the generator in a forrest you can take it out and leave it out. Jack

[DSchmidt_2000]

Well, officially we don't know for sure. OP needs to post if the RPM's are lower or the same. A kill-a-watt to measure the output freq would seal the hypothesis. Also knowing what the load is would help as I would expect the RPM's would be load dependent with increasing backpressure.

It may not be carbon buildup but it is certainly a path to take. Saying that it is DEFINITELY it is just a guess too.

OP really needs to do some measuring and trouble shooting and not just blindly replace.

[PaulJ2]

MrWizard wrote:

I suspect the people who are happy with them haven't reached the failure time between 100 and 150 hours.

Evidence it's not putting out the same power? Less power to my 120 volt appliances - my blender slows; my box fan slows, and it stops charging my batteries worth a damn. The generator gets quieter toward the end of its life too, and eventually it won't even power my little TV.

this is significant info
sounds like the engine is slowing down do to 'carbon clogged' exhaust
fan motor and blender motor speed are directly related to the 3600 rpm needed to maintain 60 cycle power and electric motor speeds



reduce speed to 3000 rpm and power is now 50cycle 100v

what oil are you mixing in the fuel

try using 2-stroke 'MOTORCYCLE' injection oil, yes it can be used in premix
TCW-3 rating synthetic blend, it burns ash & carbon free

buy it at the motorcycle shop, or pepboys, don't use cheap weed eater oil

Now we are getting somewhere. Engine loss of power. Clean carbon from exhaust and muffler and restore all the power.

[MrWizard]

I suspect the people who are happy with them haven't reached the failure time between 100 and 150 hours.

Evidence it's not putting out the same power? Less power to my 120 volt appliances - my blender slows; my box fan slows, and it stops charging my batteries worth a damn. The generator gets quieter toward the end of its life too, and eventually it won't even power my little TV.

this is significant info
sounds like the engine is slowing down do to 'carbon clogged' exhaust
fan motor and blender motor speed are directly related to the 3600 rpm needed to maintain 60 cycle power and electric motor speeds

reduce speed to 3000 rpm and power is now 50cycle 100v

what oil are you mixing in the fuel

try using 2-stroke 'MOTORCYCLE' injection oil, yes it can be used in premix
TCW-3 rating synthetic blend, it burns ash & carbon free

buy it at the motorcycle shop, or pepboys, don't use cheap weed eater oil

[mlts22]

I know the ET800 clones are seductive because they cost about a C-note. However, there are plenty of YouTube videos showing how spiky/dirty their power is.

They have a place -- if one cannot afford better, you have to do what you can, no shame in that. They are also OK as true emergency generators, assuming they can power a sump pump or other items.

However, if I had to buy a generator on price, I would go with the above mentioned Champion. I would guess it comes off the same Chinese factory lines as the no-name brands, but CPE has a very good reputation for supporting their products with parts and tech support.

No, it isn't a red/blue, but it is something that you won't have to buy ten of. The local Tractor Supply has them at $329.99, so for the price of a couple of the cheapies, one can have something that will last a long time.

[JiminDenver]

I was thinking about the converter too. Is it possible that you are not overloading the generator but are pushing it for four hours a day and that might be creating the extra heat causing the failures? I know our converter pulls enough power that the Champ has a hard time running the AC at the same time. If the battery is low I have to wait till it come up some and the draw drops. With the converter off the AC starts up like on shore power even at 9-10,000 ft

Possibly a stand alone charger that takes less power would be better.

[DSchmidt_2000]

dragonflyspit wrote:

DSchmidt_2000 wrote:
What is your evidence that it is making less and less power over time? I don't see where you mentioned that. Is the engine not running?

I suspect the people who are happy with them haven't reached the failure time between 100 and 150 hours.

RPM the same? Engine speed = output frequency. Lower RPM, less output frequency, and AC motors run slower. Voltage output also drops with RPM.

Quieter can just mean less of a load on the engine, not necessarily that something is wrong with the engine.

Suspect as the Wizard wrote

a likely cause of failure is the 'diode & capacitor' used to supply the Dc field of the armature winding, heat is a killer of cheap capacitors, lack of field strength would mean lower output voltage

[dragonflyspit]

DSchmidt_2000 wrote:
What is your evidence that it is making less and less power over time? I don't see where you mentioned that. Is the engine not running?

I suspect the people who are happy with them haven't reached the failure time between 100 and 150 hours.

Evidence it's not putting out the same power? Less power to my 120 volt appliances - my blender slows; my box fan slows, and it stops charging my batteries worth a damn. The generator gets quieter toward the end of its life too, and eventually it won't even power my little TV.

SaltiDawg wrote:
There are a few youtube videos where self-proclaimed experts open up a brand new HF genny and show the steps to remove various components, sometimes finding some fasteners were not torqued at the factory during assembly. These folks then properly torque these fasteners and sometimes advocate thread locker such as Loctite.

I'm going to have to look those videos up. Tightening things down on some of them would be helpful at least in quieting them. Some of these things buzz, bang, and rattle like crazy right from the start. You can tell parts are loose. Bolts, nuts, & plates fall off or out of many of them. The last one was especially noisy. This most recent one is either particularly quiet, or it just seems that way in contrast.

The RV batteries had gotten so low on the last one that my little inverters would alarm and shut down when I tried to charge my phone. This newest one charged them up again pretty quickly.

BTW, I've gone through both the blue and red versions of the little genny. They paint them a different color and slapped a new brand sticker on them, but as far as I can tell, the red one are exactly like the blue ones were.

[DSchmidt_2000]

MrWizard wrote:
problem is Not the copper windings
residual magnetism of the core could fail from heat fatigue
but as long as there was enough to 'excite' the core on startup the generator would continue to make power
a likely cause of failure is the 'diode & capacitor' used to supply the Dc field of the armature winding, heat is a killer of cheap capacitors, lack of field strength would mean lower output voltage

we are not there, we do not even know if it is maintaining full 3600 RPM's
any change/loss of speed would reduce power/voltage and watts
how big is the charger/converter ? being powered by the genset

Exactly my point. Not enough info given to even help. To just say 'get a red or blue' generator does not help this guy.

2oldman wrote:

DSchmidt_2000 wrote:
A lot of people have been happy with these.

Then they should be posting here.

People that buy these are not likely RV-ers, probably don't even know this place exists. All the RV'ers here like quiet Red and Blue generators. There's posts on this generator on survivalist websites, and on HF itself.

[MrWizard]

problem is Not the copper windings
residual magnetism of the core could fail from heat fatigue
but as long as there was enough to 'excite' the core on startup the generator would continue to make power
a likely cause of failure is the 'diode & capacitor' used to supply the Dc field of the armature winding, heat is a killer of cheap capacitors, lack of field strength would mean lower output voltage

we are not there, we do not even know if it is maintaining full 3600 RPM's
any change/loss of speed would reduce power/voltage and watts
how big is the charger/converter ? being powered by the genset

DSchmidt_2000 wrote:
Something does not make sense and I don't see any root cause analysis being done as to why your units are crapping out. Just saying they're cheap doesn't cut it.

A lot of people have been happy with these. As long as the engine can put out power and the electronics (capacitor?) works, I don't see why it should not continue to work. There is not much to them. Why would copper winding give out after time?

For a 2-stroke, after about 100 hours don't you have to clean out/decarbon the exhaust?

What is your evidence that it is making less and less power over time? I don't see where you mentioned that. Is the engine not running?

[SaltiDawg]

There are a few youtube videos where self-proclaimed experts open up a brand new HF genny and show the steps to remove various components, sometimes finding some fasteners were not torqued at the factory during assembly. These folks then properly torque these fasteners and sometimes advocate thread locker such as Loctite. Most if not all advocate replacing the spark plug with a US Brand rather than the Chinese brand that it comes with.

What we don't know is whether these steps REALLY do help.

[2oldman]

DSchmidt_2000 wrote:
A lot of people have been happy with these.

Then they should be posting here.