Who knows about generators?

[V8Ian]

I have a non-running Honda genny. It has been attacked by a dog, who chewed off the spark plug lead, and is siezed. I have never heard it run, but the symptoms described to me make me suspect big end/crank failure. The motor is a Honda 8 hp. Specifically I would like know:
1)Is this motor worth spending money on?
2)The alternator is old, and presumably not pure sine wave (what ever that may be), as such, is it suitable to power a computer or domestic fridge?
3)Is the alternator worth re-powering?

[Bigbjorn]

Ian, if you need major OEM parts for anything with a Honda nameplate you are going to be ripped off mightily. Also, Honda practice ruthless obsolescence programmes and parts for older Honda equipment are removed from the system around the 10 year mark. Why not open it up and see what is needed. You may be able to acquire from after-market and pirate suppliers at much better prices than from Honda dealers.

[V8Ian]

Yes Brian, a Land Rover muffler is cheaper than a Honda mower one! :o
I know nothing about the generating end, and was wondering if it was worth repowering. Much of Innisfail is still without power and as far north as Deeral. :(

[isuzurover]

I know nothing about the generating end, ...

Mecc Alte S.p.A is one of the largest generator manufacturers - so should be good quality.

I would open the motor and see what is needed.

[Tank]

Last time I owned a honda powered anything was a long time back, 25 years ago. they were a throw away motor, my Honda pump had a bottom end knock so I decided to replace the big end bearinig. trouble is Hondas didn't have bottom end bearings, the con rod ran directly on the crank and to replace you had to buy a new rod and piston as a unit and it was more than the price of a similar size Briggs and Stratton. Ended up scrapping it , Regards Frank.

[V8Ian]

Mecc Alte S.p.A is one of the largest generator manufacturers - so should be good quality.

I would open the motor and see what is needed.
Being able to generate in excess of 4 KVA, it should have no difficulty in powering a house, but is it the right type of power? I've heard of fridges blowing up on generators. What is 'pure sine'? Is it essential for certain appliances?

[bee utey]

Last time I owned a honda powered anything was a long time back, 25 years ago. they were a throw away motor, my Honda pump had a bottom end knock so I decided to replace the big end bearinig. trouble is Hondas didn't have bottom end bearings, the con rod ran directly on the crank and to replace you had to buy a new rod and piston as a unit and it was more than the price of a similar size Briggs and Stratton. Ended up scrapping it , Regards Frank.

My Honda powered mower is still going, 16 years after I filed down the big end cap to correct the clearance. Previous owner had run it with a sump full of petrol. :p Which is why I got it for nothing.:p
You may be able to break the engine loose with some CRC down the bore, but don't waste too much time on making it perfect. Unless you find a matching motor off a burnt out genny you won't do it cheaply.

[Redback]

Being able to generate in excess of 4 KVA, it should have no difficulty in powering a house, but is it the right type of power? I've heard of fridges blowing up on generators. What is 'pure sine'? Is it essential for certain appliances?

Yes it is, especially for medical devices and delicate electronics, it esentially doesn't surge, which will kill things like computers and the like.

Baz.

[V8Ian]

I'm thinking a new Honda may be the go. Where's Fluids? ;)

[isuzurover]

Being able to generate in excess of 4 KVA, it should have no difficulty in powering a house, but is it the right type of power? I've heard of fridges blowing up on generators. What is 'pure sine'? Is it essential for certain appliances?

Any good quality generator should produce a pure sine wave, as that is inherently what alternators produce (car alternators produce AC, which is then rectified to DC).

It is inverters that often produce a "Square wave" or "modified sine wave"
https://www.aulro.com/afvb/images/imported/2011/02/1019.jpg
This image shows the difference. Proper 240V AC cycles between -240 and +240 V 50 times per second. Cheap inverters clip the dc and invert the voltage 50 times per second.

So in short, your generator should produce a pure sine wave. The only issues will be how close the governer and the genset can keep the power to 240 V and 50 Hz. AFAIK that is the main problem with gensets, not the waveform.

[JDNSW]

More or less as Isuzurover says, although for reasons I won't go into, the output is not really pure sine wave - but neither is the mains power! The generator is likely to have fairly unstable frequency and voltage - mains power varies quite a lot on voltage, but has generally very good fwequency stability.

Modern appliances including computer equipment are rarely frequency sensitive, but anything with a motor will not be happy if voltage is well below 230, and most electronic gear is liable to failure if voltage gets much above 260. Generally speaking, no domestic appliances will have problems with this sort of generator, but 4kva is not really enough for a modern home, in particular, you need caution with any cooking, heating or airconditioning equipment.The big problem is that when an electric motor starts, it may use several times its normal power - so, for example, your fridge may use, say 250VA, but use 1000VA when the compressor starts. Have both it and a deep freeze starting at the same moment that you are running the microwave (which takes probably 2500VA), and the maximum generator output is exceeded. So what happens? Well, once the throttle is fully open, the governor can do no more to keep the generator speed up, so voltage and frequency start to drop. As the voltage drops, the motors, and the microwave, will draw more current, exacerbating the situation. Unless there is an overload circuit breaker or fuse, the situation will rapidly deteriorate until at least one of the heavy loads or the alternatort itself ceases operation (permanently), usually with a cloud of smoke. The whole process may take about less than about 30 seconds. Fortunately, most, but not all, generators have a fuse or circuit breaker.

I would suggest that to run most modern houses, you need to have around 9KVA, although the actual draw will probably average only about 2KVA or less. But, of course, you can make do with a 4KVA generator if you use it only for essentials, say fridge, freezer, a few lights and maybe a computer and a fan.

John

[Homestar]

Mecc Alte S.p.A is one of the largest generator manufacturers - so should be good quality.


I know some people that swear by Mecc Alte gear, bit we know these alternators at work as "Mecc FAULTY" as we have more of this type fail than any other. We don't buy gensets with these alternators on them any more, and we are phasing out the ones we have. The only way to get a decent like span out of one, is to have the windings double dipped or marinised before use, but no other alternator manufacturer requires this, so I think it is a bit of a cop out to cover up thier unreliability. Personally I would recommend Stamford alternators - less failures, simpler design, easier & cheaper for parts, and less harmonic distortion than most others.

I agree with what JDNSW says about things, and you should get away with running the essentials of your house on a 4KVA, but I wouldn't want to turn the AC on or anything like that, and make sure the voltage stays stable and between 230 to 260 volts.

[incisor]

honda do what they call (or did call) "high frequency" generators. these are by far the best thing for computers and other sensitive electronic devices like tv's etc etc.

normal gensets are fine for motorised stuff like fridges and washing machines and also for lighting.

[PhilipA]

I ran my fridge on Saturday night and Sunday on my Yamaha 800VA EF1000 , including a 150W bulb to give resistive load.
It stalled a couple of times when I connected the fridge load , but was OK from then on.
Seeing the load was only 500VA it was running at about 52HZ or so.
BUT it did a great job.
Regards Philip A

[Blknight.aus]

be very quick, put it in the back of the disco bring it to my place and bring it around I'll load it on the work truck and use it as a "something to do" project while on ex.

[V8Ian]

Thanks for the offer Dave, I genuinely appreciate it. The only hicough is that I'm back in FNQ, so "be very quick, put it in the back of the disco bring it to my place" may present a logistical dilemma.:D Let me Know when you're back up the top, I'll organize some refreshments. ;)

[LandyAndy]

Gidday Ian
You may be able to get a chink copy Honda mojo to strap to the alternator to get you thru.
Should be cheaper than a rebuild.
Andrew

[V8Ian]

Thanks Andy, atm I'm using an el cheapo Homelite, it can't run a fridge so a 60 k daily drive for ice, but it's good enough to charge the land line, mobile, lappy and run a fan and bedside light.