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Posted By: Jps1006 Work truck inverter/generator? - 04/12/05 09:30 PM
Is there generator I can hook up to the drive belt of 2000 Ford V8 like an alternator to get 4000 watts of 120/240 power?

Wouldn't it be nice to always have your generator with you? Never have to change the oil, make sure the gas is still good?

How about inverters to run tools? You guys ever use them?

My brother wants to get rid of his portable generator and replace it with either an inverter or some type of generator that runs off the engine. But he wants it 240 volt 20 amp incase he needs to run his well in a power outage. Ever heard of it??

How many of you guys use an inverter for tools?
Posted By: highground Re: Work truck inverter/generator? - 04/12/05 11:01 PM
I have an inverter in my truck, and it works pretty well. I think it is 2000 watts. It draws some serious DC from the batteries. I ran 1/0 welding cable to it under the seat of the truck. You couldn't use it all day long without boosting the idle speed of your truck. It shuts itself off when the DC voltage drops below 11V. It's great to have with you all the time.
Posted By: renosteinke Re: Work truck inverter/generator? - 04/13/05 01:09 AM
Check the off-road magazines and suppliers....these guys have monster alternators with lugs on them for attaching welding leads. I'm not sure of the volts, etc...but I'd be surprised if they don't have something for you.
Posted By: Active 1 Re: Work truck inverter/generator? - 04/13/05 02:59 AM
They have PTO generators that are conected to the transmission. The trans has to come with a special PTO port. Not very common. Seen more in 1 ton manual transmissions.

I would not plan on using an inverter to run power tools for long periods. Do the math. With my math to get 10a 120v you need around 100 amps at 14 volts. Stardard alternators max out in the 100 amp range. They are not made to run at max very long. You also have to figure it takes maybe 20+ amps from the alternator to keep the truck running.

If you did run an inverter for more than small loads run the power wire back to the alternator lug. You ever notice the size wire they use from the factory on the alternator. Most are #10 or #12. Adding a 2nd battery would not hurt.

They do have belt drive generators. You would have to make the pully turn at 1800 or 3600 rpm. Good luck trying to get a ford to run at a steady RPM. Trying to come up with a bracket belt set up sounds like a project.

Ford did have a duel alt option in ambulances with larger alternators.

An RV generator I beleve hooks in with the trucks fuel system and 12 electrical for starting. Maybee it could be mounted under the truck.

You may save a little maintence on a portable generator but you put the wear on the truck. The truck probibly uses more fuel to run. Ideling trucks all day long is not the idel life for them. The price of a truck engine you could buy a few generators.


You wanted 240v at 20amps (8,300 watts) to run off a 12v Ford. Your crazy.

Posted By: JCooper Re: Work truck inverter/generator? - 04/13/05 03:11 AM
You could go with a hydraulic driven generator, you add the pump to your belt system and you can get a generator as big as you can afford.
Not that this will help, but I've seen a unit like you want. 120/240V 4kW and it operates at full wattage at idle.
I just do not know who made it.


The unit was not an inverter it was a gen that mounted under the hood.

[This message has been edited by sierra electrician (edited 04-13-2005).]
Posted By: Alan Belson Re: Work truck inverter/generator? - 04/13/05 07:41 AM
1. Inverters. One word? DON'T! 4kW-5kW off a 12vdc vehicle battery? - I make that over 400A. Vehicle batteries are not designed for this type of application and will fail pronto-they like a short burst and immediate full recharge. You need separate 'deep-draw' batteries (ie golf-cart type). These are cheap, but have a limited life. You should only discharge them 50% for longer life- even then you'll be lucky to get over 300 charges before new ones required....
2. Run a gennie on the V8. Sounds good on paper, but.......Gasoline engine= no governor= variable speed at the alternator shaft= fluctuating hz. and volts. That won't bother power tools/wellpump, but don't plug your computer into it! Also, you'd be heaving the alternator round all the time when not using it- no promlem for the V8, but an alternator running at 2 or 3 times its design speed when you gun the V8 might have. Less mpg too, the alternator needs power even on idle for its cooling fan. Not sure how you get speed contol -hand throttle? -on a modern engine with electronic injection, and of course there's the engine temperature to consider= electric fan almost mandatory. But it would work, the alternator will be a lot cheaper and lighter than inverters and batteries. With all the above limitations in mind, for 5kw (6.7hp) youll need duplex (2)x 1/2" vee belts = custom crank pulley, duplex alternator pulley. Bracket needs to be strong, aligned properly & adjustable for belt tension, with room round the alternator for air/access. Make sure belts have good arc of contact. As to the 120-240V AC wiring /switchgear/ breakers/ grounding out of the gennie, I can't comment as I'm English, but I'm sure the members will post some good advice- so watch this space!
Posted By: IanR Re: Work truck inverter/generator? - 04/13/05 11:17 AM
Check these out

You will have to find a way to keep the motor speed constant though.
Posted By: Active 1 Re: Work truck inverter/generator? - 04/13/05 03:22 PM
RV's and some other trucks use something like this:

If you had a pulley driven gen you need to do the math for pully sizes which changes driven speed. A computer controled truck is should to idel at what it is programed to do with the engine sencer readings. For that reason it will not be consistant. You could try a throtel control to around 2000 rpm. I think you would find the RPM would not be concistant. Emmision system kicking on and off, A/C if on, air temp, and surges in puwer would cause problems. If you wanted to go all out you cou use an electronic RPM limiter like from MSD but just that woud set you back a few hundred.

Also figure if it's summertime the cooling system and auto trans will not handle runing the engine at 2000+ rpm in nutral for long periods. It is designed to have air flowing thru the radiator/trans cooler from the truck driving down the road. Then again you could add electric cooling fans and a trans cooler for a few hundred.

A lot of things are possable if you put the time and $$ into it. Reliability, financially, wear and tear on truck, and engenering time bolting on a gen to the truck engine is not a good choice.

Posted By: Alan Belson Re: Work truck inverter/generator? - 04/13/05 04:10 PM
Just finished talking to a 'Perkins Diesel' engineer friend of mine, you need a governor- - he suggests contacting AMBAC, used to be American Bosch - he seems to think they do electric gasoline engine governors.
Must agree with Tom though- probably cheaper to stick with a gen-set- Honda do a nice line now- check out the 1000i/2000i range-you can link these together to form multiple units of a larger size.
Posted By: Jps1006 Re: Work truck inverter/generator? - 04/14/05 02:42 AM
Great suggestions guys. Thanks. I'm intersted in Ian's link. I'll post if I find anything else out. I might check the price on that, even though I don't know if it would fit under the hood. Thanks again!
Posted By: Active 1 Re: Work truck inverter/generator? - 04/14/05 02:21 PM
If your looking for a price & specs on a belt drive:

$805 +SH
120 lbs
size 19"x13"x9"
Needs to turn at 3600 rpm

The htz and volt output is related directly to the rpm of the generator. A govener like Alan said would be the ticket. Good luck fitting the gen under the hood.

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