How much power can these spur gears handle?

You are right, I keep forgetting you are not going for full potential.

My current project is this little Honda 1600. In got it free planing on parting it out. Looks like it took a dive off the back of a truck. It would turn so far, and stop. I thought it threw a rod, and bet the PO thought the same thing. When I opened it up, it had dropped a valve. I'm thinking that when it got dropped, the valve spring compressed enough to let the retainer pop off. The valve was the only casualty. Cylinder, piston, and all insides look great. I got a set of valves, also picked up a new carb, ignition parts, rewind starter, and some other small stuff, for less then $20, Just waiting on the gasket set, then I will hope I can remember how it all fits back together.


100_0749.JPG

The future project, is this 5kw head. I have a PTO that will mount to the NP435 in my pickup. I planning on using a half shaft off a minivan, as the drive shaft. Then likely a set of pulleys to get the right speed (Still have not calculated the output speed of the PTO). Right now, the plans are to have it run at the 3600 RPM, while the engine is at idle, and have a switch mounted to the gas pedal, or a speed sensor, to shut down the engine if the RPMs get above the idle, or 3600 at the gen head.

100_0744.JPG100_0745.JPG

I also have 2 military generators (3KW, and a 1.5KW), that I would like to get running, just need some more roundtuits.
 
I would think your cheapest option is to buy an old truck motor and power the genset direct coupled.......dunno about US,but an old Cat 3406 can be bought for scrap price,same with GM s...around $500
 
I would think your cheapest option is to buy an old truck motor and power the genset direct coupled.......dunno about US,but an old Cat 3406 can be bought for scrap price,same with GM s...around $500
Cat engine around here can't be had for any price close to reasonable. And even if someone gifted one to me, I couldn't afford the rebuild parts. But a GM 5.7L, yeah I could get that for <$500 for sure. Problem is, 1800rpm is low for a gasser. They have no power down there. Searching online for a dyno graph of a stock 350, If you can even find an example that goes that low, you'll see they have less than 50hp down there, about the same as my tractor which I already have and don't even need to spend $500 for. If I wanted to use a GM 350, I'd need* to run it at a decent rpm and gear it down. And then I'd be right back where I am now.


*I suppose I wouldn't actually need to. I could just go ahead and direct couple, and accept the low power output since it's probably sufficient anyway, but then I'd still be paying for an engine and all that goes along with it, which might cost as much or more than the gearing I need to make it work with the tractor. It deserves more thought and investigation. Any idea what kind of fuel economy an old 350 would have, being run so far away from peak efficiency?
 
Kinda out of the box thinking, Get a gasser with a manual tranny. If you do not need much power, you run it in 4th gear (or which ever has the 1 to 1 output for the tranny), and run the engine at the 1800 RPM. Need more power, and shift the tranny to third (Usually close to a 1, something to 1 ratio), and run the engine at the right speed to get the 1800 output RPM, like 2600 or so. Gobs of power, shift into 2nd, which is usually 2.whatever to, and run the engine at the approx 3800 or so RPMs.
 
I was interested in your comment about the friction with belts. Belts are a very efficient means of power transmission and quiet and don't need lubrication.
The .zip file has a demo calculator in it. The only stuff dedicated to synchronous drives is in hard copy sorry but there is a little bit in the Gates catalogue. The Opti-belt one has some calculations on page 90.
Synchronous drives,(timing belts), are readily available up to 150 kW,(think motorcycle), and more with special order, meaning not in the back room of your local dealer. Not sure of the max ratings on Polly-V belt as larger power ratings usually go for linked back V.
Most PTO's regulation is pretty good within working range on modern tractors so a clutched,plate or cone, gearbox is definitely a go.
 

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Kinda out of the box thinking, Get a gasser with a manual tranny. If you do not need much power, you run it in 4th gear (or which ever has the 1 to 1 output for the tranny), and run the engine at the 1800 RPM. Need more power, and shift the tranny to third (Usually close to a 1, something to 1 ratio), and run the engine at the right speed to get the 1800 output RPM, like 2600 or so. Gobs of power, shift into 2nd, which is usually 2.whatever to, and run the engine at the approx 3800 or so RPMs.
That's basically the idea behind the jeeperator except it's automatic so if someone turns on the dryer while it's in 4th gear and sipping fuel, it will downshift automatically and I can stay in bed. Or at least that's the way I see it working. I can't find evidence of anyone else having made a generator work with an automatic transmission, so that probably means that it I doesn't. I'm sure people have tried it, but how many people run to YouTube to document their failures?
 
I was interested in your comment about the friction with belts. Belts are a very efficient means of power transmission and quiet and don't need lubrication.
The .zip file has a demo calculator in it. The only stuff dedicated to synchronous drives is in hard copy sorry but there is a little bit in the Gates catalogue. The Opti-belt one has some calculations on page 90.
Synchronous drives,(timing belts), are readily available up to 150 kW,(think motorcycle), and more with special order, meaning not in the back room of your local dealer. Not sure of the max ratings on Polly-V belt as larger power ratings usually go for linked back V.
Most PTO's regulation is pretty good within working range on modern tractors so a clutched,plate or cone, gearbox is definitely a go.
You're right. I remember being wrong about the efficiency of v-belts the first time I went through this. I forgot that lesson. It does not seem intuitive to me that they are efficient but they are.
 
You are right, I keep forgetting you are not going for full potential.

My current project is this little Honda 1600. In got it free planing on parting it out. Looks like it took a dive off the back of a truck. It would turn so far, and stop. I thought it threw a rod, and bet the PO thought the same thing. When I opened it up, it had dropped a valve. I'm thinking that when it got dropped, the valve spring compressed enough to let the retainer pop off. The valve was the only casualty. Cylinder, piston, and all insides look great. I got a set of valves, also picked up a new carb, ignition parts, rewind starter, and some other small stuff, for less then $20, Just waiting on the gasket set, then I will hope I can remember how it all fits back together.


View attachment 284980

The future project, is this 5kw head. I have a PTO that will mount to the NP435 in my pickup. I planning on using a half shaft off a minivan, as the drive shaft. Then likely a set of pulleys to get the right speed (Still have not calculated the output speed of the PTO). Right now, the plans are to have it run at the 3600 RPM, while the engine is at idle, and have a switch mounted to the gas pedal, or a speed sensor, to shut down the engine if the RPMs get above the idle, or 3600 at the gen head.

View attachment 284981View attachment 284982

I also have 2 military generators (3KW, and a 1.5KW), that I would like to get running, just need some more roundtuits.
What kind of truck do you have, which has a PTO? I continue to window shop (as I have for the past 2 years) for a new truck, and was particularly interested by Ram's optional offering of a PTO. I did not see that available on any of the other trucks. I can think of all kind of cool stuff to do with a PTO on a truck. I googled NP435 and saw that it went out of style in 1997 so I assume it's an older model pickup?
 
Its a 90 Dodge W250. Its one of the newer trucks in my fleet. Most are 77 Dodges. I also have a PTO that will mount to a NP203, from the 77. It will power a PTO driven Ramsey winch.

The NV4500 which basically replaced the NP435, has PTO openings, but good luck finding a PTO that will fit. I do not know how long or if it is still used. I just like trucks that do not cost a fortune to buy, and keep running.

Intriguing idea with the auto tranny. I've been thinking it through all day.
 
Looking at the use of an automatic tranny, I would think an electronic cruise control could control the engine rpm under variable load. I think that having the speed sensor on the driveshaft is the way to go. Some new cars are using the ABS sensors to tell the PCM what is happening. The PCM then controls the engine. Problem could be finding a cruise control kit to do so!
 
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