On board 240V A/C power

[MAster-O-Turbonics]

I'm looking to have a welder and a lot of other gear mounted on my lighter weight truck, and am looking for 8000+ watts of power to run either a TIG welder or a strong air compressor in the field.

I'm running a nissan 720 pickup manual transmission and divorced transfer case behind a 2.2 Nissan diesel. I would try to go off the crankshaft pulley, but the crankshaft only has a 1 rib pulley that is already turning the water pump and alternator.

Basically I don't want a 500Lb generator on board, if I could have that power available from a sub-150 pound setup.
Just shift the transfer case into neutral and slide the V-belt onto the drive pulleys using some sort of quick tensioner. A V-belt (and an extra one) would be zip-tied around the top of the transfer case or rear of the transmission when not in use.

Is there a feasable way to run
THIS off of a V belt attached to the input shaft of the transfer case?

basically taking this

and running it off of the input flange of this transfer case via a v-belt and extended input shaft supported by pillow blocks to put the generator head behind the cab.




Unfortunately this is about the most detailed picture I have of how the transfer case is laid out, for those of you not familiar with the 720 drivetrain layout.

Thoughts? Opinions?
Any problems running a generator head off of an input flange?

Obviously I'd need to figure out pulley sizes for the proper RPMs of the generator head.

[braxton357]

Since you're running a divorced tcase...could you not find something with a pto? I'd have to imagine it would make things easier. Your idea would probably work but it would take 5 or more v belts to support 18hp at 4krpm I would imagine. And how would you just slide a belt over the tcase input shaft?

[MAster-O-Turbonics]

The belt would have the driveshaft through it already, just pushed over the top of the transfer case and secured when not in use.
Thats a little trick the nascar guys use for their 3rd member oil pumps, is to have an extra v belt zip tied to the driveshaft hoop just in case you lose a v belt.

Maybe a cogged belt could be used.

[billy bones]

You could run some type of split shaft pto between the trans and transfer case. Direct drive the generator and use the transmission gearing to get the proper RPMs.

http://www.munciepower.com/products/...ower-take-off/


Or swap out the t-case for something with a pto already on it.

[dwilliams35]

I'd just put a hydraulic pump driven with the input shaft like you mention, then run hoses to the bed or wherever to run the generator. Also, instead of using the belt-drive head you have, if needed you could get their PTO generator head: takes a lot less input RPM, since it's already got a reduction unit on it.

[ChiScouter]

Find a way to mount it with an electronic clutch with a double v belt and run it directly off of your crankshaft on the front of the engine

[carcrafter22]

I don't think I would run a V belt for this setup for many reasons, I'd go with the PTO idea, way better in the long run.

[ChiScouter]

Originally Posted by carcrafter22

I don't think I would run a V belt for this setup for many reasons, I'd go with the PTO idea, way better in the long run.

Why don't you explain all those many reasons?

[chevy_man]

He could start with they suck and don't hold any torque.


I've got a 720 sitting out back, but with the gasser. I've had more trouble keeping the v-belt adjusted on that thing to keep the alternator going than I've ever had with all my serpentine setups combined.

The v-belt is cheap, but I don't think it can handle what you're thinking without running 3 or 4 of them. You'd be better off to find a PTO and run it direct.

[dwilliams35]

That plus the pain in the ass it'll be to change belts when needed, having all that crap underneath the rig to catch every limb and rock that it comes across, and the basic premise that it's ghetto.

[gavan]

We ran a big ass gen head off a Allison PTO behind a Cat 3116 for a mobile rhino lining truck. The high pressure sprayer runs big heaters and pumps, plus you need a big supply of air, so we were running a big 3 phase compressor and the 3 phase high pressure machine. I so not remember off the top of my head how big the genset was, but 20,000 watts sounds about right.

We did not want it hiding out under the truck getting filthy, so we ran a belt drive into the box. Big cogged belt. You might not as big of a cogged belt, but I would recommend running one. That fucker sounded pissed off when it ran and you could tell it was pumping out some power.

Also you need to worry about RPM output. We had an electrinically controlled motor that you could rev up with the cruise control, and it would keep the RPMs constant. With the ineffencies in the gen head we would still get voltage drop when running it heavy and we would need to bump it a few RPMs to keep output voltage right. It was not a huge deal with the setup we had, but if you have something sensitive that will not like voltage swings you need to get a motor controller to match rpms to voltage output, and those are not cheap.

How is the pump set up on that sucker? Some automotive pumps will start to creep up RPMs under boost at constant throttle, which is not at all what you want when running a gen head.

Is the transfercase even rated for prolonged high RPM input while shifted in neutral? I could see some cases not flowing enough oil to keep it cool and burning out a bearing.

Basically you are looking for big power while spending small money, which usually does not work out so well.

I think the best/easiest with that motor/drivetrain setup is a hydraulic head like someone mentioned.

[Soundguy]

Just weld up a coupler and attach the generator head to the rear output on your t-case. Remove the rear drive shaft and make it a FWD rig, problem solved. You'll have all the AC power you could ever need on the trail.