I don't think I have ever seen a small engine work so hard in my life. It took it like a champ. Probably wouldn't be a good idea to do too often though lol.
I made one of these 35 years ago , same setup , 1 wire gm alternator , 3 hp Briggs & Stratton engine , went to use it and attempted to pull 30 amps -it killed the motor right there and the whole assembly jumped up a couple inches lol , found out alternators take a lot more than a 3 hp engine to produce any usable amount of current . Took it all apart and scrapped the idea lol 😦
You are Correct. The wattage output is converted to horsepower that is increased by an estimate of loss factor. That higher figure is doubled. That figure is the minimum horsepower internal combustion engine required. His experiment proved that. His engine did not have enough excess power for the governor to respond to the step load. This factor has been long known. Edison probably discovered that soon after he learned the governor shafts of his parallel DC generators had to be synchronized.
i built one of these a few years ago using a honda gx200 6.5hp engine and a delco 10si 120a alternator. i did not use a one-wire unit because i wanted to be able to start the engine with no load and let it warm up a bit before switching on the charging system. it's really hard on an alternator's diodes if you connect/disconnect the battery with the alternator spinning..
This is exactly what I needed to see to generate (no pun intended) an idea to fabricate brackets and mount an alternator on my Honda GX160 for my mini power trowel. I'm mounted four mini truck lights and needed to figure out how to generate the power for them. This is it! Thank you!
I'm doing a 13hp Harbor freight engine with a 400 Amp alternator. I've seen many problems with gearing. I'm doing 3 to 5 on the gear ratio. The Alternator only needs 1200 RPMS to max out amperage. Max Torque on the engine is at 2500 RPMS. 3 to 5 ratio is 1500 RPMS with more added torque.
@@Bodgemiester Ive actually have been doing calculations since I sent the message. I also found out the posting said 400 Amps at 1200 Rpms. This was car engine Rpms. I have to spin up the alternator to 4800 Roms to achieve the 400 amps. Reading and understand torque is very important before buying the motor. I've also noticed the hit on the motor when connected to the battery. I'm thinking of adding a 3 or 4 Kg flywheel to absorb that initial hit from the alternator. Been looking at Elliptical flywheels. This is not a free energy project. They dont work. There is nothing like it on the net. I should video it. Also, I haven't seen a 400 Amp alternator generator set up on UA-cam.
Wow, nice build. Have you considered gearing the pulleys on your apparatus. Maybe the alternator could be running at half speed of the engine giving a 2 to 1 advantage for the engine. Eg. the pulley on the alternator could be 10 cm in diameter and the engine pulley would be 5 cm in diameter. This would reduce stalling. Thanks for sharing.
Actually the pulleys sizes should be reversed. An alternator needs to spin at least 5,000 rpm to get decent output. Put the bigger pulley on the engine, smaller on the alternator for overdrive.
How to cook an alternator: Disconnect the load (battery) with the engine running. Engine is too small for the alternator. 85 amps @ 12 volts is 1.02 kw. 1020 watts/746 is 1.37 hp. Single vee-belt transmission efficiency is around 90%, bringing the required power to 1.52 hp. If you add the alternator's 55% efficiency, that brings the power required to drive it to 2.76 hp. Thus the engine is overloaded and bogs down when the alternator loads it down. A 65 amp alternator would be the biggest alternator that engine could realistically handle. Nice videos. Cheers.
that generator gives 100 ampere just in the beginning , thats whay the engine stalled out . when the generator is produsing for full you need a motor on 5 HP to make it work . this is just in the beginning of the charging cyckel , then the powertake out drops very fast down to 70 ampere and thats why youre engine have to work so hard in the beginning and it runs lighter and lighter the more it fills up the battery. i have built one to with a honda clone and i dont recommend you to change the pully on the motor to a bigger one becourse it will get hard to crank over to start up . best wishes from sweden 😊😊
Get a predator 420 with electric start on here . And just for fun put the a motorcycle twist throttle on the dolly then you can have fun revving it up while pushing it around
So what would happen if your battery wasn't flat? Say you just wanted to maintain the battery and subject it to a kilowatt load? Cool Volvo. I wish we would have gotten the 3-series cars here in the US.
The 300 series was totally different, it was RWD with a transaxle, an excellent car, I grew up in the back of one. The 400 series was built at the same place in Belgium but front wheel drive and nothing like as well built but still a nice drive
You need to do a few calcs and read up on this stuff. 100A @ 13.8 volts to charge a battery is 13.8x100=1380w, but the alternator is only about 50% efficient, so you need at least 2760w input power, and the alternator will not give full output till its spinning around 8000rpm, the single belt on small pulleys wouldn't be able to drive the 3.7BHP that is needed, that's why it won't give you what you desire. In the car its running at high speed, a step up ratio of 2.5 to 1 is usually used, and the car can do 5000rpm. A polyvee belt is usually used on these applications, they work much better than an Alpha section belt.
+Jeff Sewell , Hi, the alternator is using its original belt pulls. I had worked out the power ratings but I had this engine ‘kicking around’. Geared 1-1 it does the job I need it to you just have to let it get over the inrush. If I re power it I’ll use a 5.5bhp engine. Just a quick toy to put on UA-cam in the end
someone needs to give you a pat on the back.it is people like you,that inspire people like me,to get off my but and build something useful and get the cobwebs of of the old internet encrusted brain cells blown out. vary cool idea. i have an OLD lawnmower waiting for an alternator now . thanks.
If you are curious about how many RPM’s that engine can manage or till it blows just hook it up on a vehicle with 24v circuit😁😁 what if many places had such generators around, how helpfull they would be up the years. Instead we throwing functionally old lawn movers on garbage
You need to use pulleys 2:1 or 3:1(small on engine and big one on alternator)first!! and then put a regulator controller, alternatorman here in YT made one and gives pointers how to make one!!
An alternator putting out 14vdc @ 100 amps equates to 1400 watts. 1 hp = 746 watts. Therefore, it will take just over 2 HP engine IN THEORY. But frictional losses generate heat. That takes a minimum 3.5 HP engine at full load. 3.5 x 746 = 2600+ watts. But that's not all to consider in the design. The engine spins at about 3600 RPM. The alternator needs to spin at about 2x that RPM to get full output. Double the size of the engine pulley and add a basttery and youi'll be able to crank a non-starting car engine all day long.
I believe you'll need around a 180 cc (aprox 6hp) engine for that alternator & a 4 inch shive (pulley). Have look at "Knurlgnar" videos. Many Years too late.......
Ha ha, you must've read my mind. Another video on this is coming out in two weeks. I will address this issue that many have pointed out. Thanks for commenting!
Cool, i consider to mount a lawn mover engine on my trunk and alternator on inside under. If clearence to rearwindow😊 i think i choose domewhere around 5-7 hp. If i find 2 alternators i might try that since they must share on the load. Convenient i found this video. I was wondering how it would be jump starting a car like that. Alternator, water pump and power steering pump take a lot of hp from the engine. In my youth i was taking a drift on kickdown while entering an empty road. The fan belt snapped and suddenly it speeded up and i was going backwards in a inferno of tyresmoke. So now i consider suxilary engine to drive the alternator, coolant etc. 😊And worst case scenario if battery is flat is to pull the rope. But maybe i should replaced my starter engine first. 3 years ago i should. Its just that a BMW designer. Must be the worst car ever to replace a starter. If i meet that designer............
A newer hairpin style denso alternator takes less torque to turn, has 12 diodes, should outlast a few generations and puts out over 2x the amperage than that old delco junk.
That tiny ground is the bottle neck, and the only reason its running at all with a load and a 1:1. Its going to overheat when you get the right ratio. no way ot can carry 100 amps! car audio people are cringing.
![Lawnmower Generator [ARCHIVED]](http://i.ytimg.com/vi/XIj7qpUZ1zM/mqdefault.jpg)
![Lawnmower Generator [ARCHIVED]](/img/tr.png)
I don't think I have ever seen a small engine work so hard in my life. It took it like a champ. Probably wouldn't be a good idea to do too often though lol.
I've since re geared it!
I made one of these 35 years ago , same setup , 1 wire gm alternator , 3 hp Briggs & Stratton engine , went to use it and attempted to pull 30 amps -it killed the motor right there and the whole assembly jumped up a couple inches lol , found out alternators take a lot more than a 3 hp engine to produce any usable amount of current .
Took it all apart and scrapped the idea lol 😦
You are Correct. The wattage output is converted to horsepower that is increased by an estimate of loss factor. That higher figure is doubled. That figure is the minimum horsepower internal combustion engine required. His experiment proved that. His engine did not have enough excess power for the governor to respond to the step load. This factor has been long known. Edison probably discovered that soon after he learned the governor shafts of his parallel DC generators had to be synchronized.
i built one of these a few years ago using a honda gx200 6.5hp engine and a delco 10si 120a alternator. i did not use a one-wire unit because i wanted to be able to start the engine with no load and let it warm up a bit before switching on the charging system. it's really hard on an alternator's diodes if you connect/disconnect the battery with the alternator spinning..
Great, I'd love to see a video of it. I have another video with this one soon!
This is exactly what I needed to see to generate (no pun intended) an idea to fabricate brackets and mount an alternator on my Honda GX160 for my mini power trowel. I'm mounted four mini truck lights and needed to figure out how to generate the power for them. This is it!
Thank you!
Excellent news!
Just add charge coils and voltage regulator
Just about to add a slow charge function and an amp gauge. Should be fun!
I'm doing a 13hp Harbor freight engine with a 400 Amp alternator. I've seen many problems with gearing. I'm doing 3 to 5 on the gear ratio. The Alternator only needs 1200 RPMS to max out amperage. Max Torque on the engine is at 2500 RPMS. 3 to 5 ratio is 1500 RPMS with more added torque.
Sounds like you're getting there!
@@Bodgemiester Ive actually have been doing calculations since I sent the message.
I also found out the posting said 400 Amps at 1200 Rpms. This was car engine Rpms. I have to spin up the alternator to 4800 Roms to achieve the 400 amps. Reading and understand torque is very important before buying the motor. I've also noticed the hit on the motor when connected to the battery. I'm thinking of adding a 3 or 4 Kg flywheel to absorb that initial hit from the alternator. Been looking at Elliptical flywheels. This is not a free energy project. They dont work.
There is nothing like it on the net. I should video it. Also, I haven't seen a 400 Amp alternator generator set up on UA-cam.
there will be about 4hp drain on the motor coming from the alternator that's why your motor lost speed.
It does, usually the peak draw drops after a few seconds and it loads quite nicely
Wow, nice build. Have you considered gearing the pulleys on your apparatus. Maybe the alternator could be running at half speed of the engine giving a 2 to 1 advantage for the engine. Eg. the pulley on the alternator could be 10 cm in diameter and the engine pulley would be 5 cm in diameter. This would reduce stalling. Thanks for sharing.
Thanks for the comment! Yep I’m going to
Re-gear it some day (never) it’s not an issue if the battery is not stone dead
Hey, as long as it works.
Actually the pulleys sizes should be reversed. An alternator needs to spin at least 5,000 rpm to get decent output. Put the bigger pulley on the engine, smaller on the alternator for overdrive.
Agreed but it is running short of power
@Bodgemiester did you ever get it to charge correctly what's your voltage
How to cook an alternator: Disconnect the load (battery) with the engine running. Engine is too small for the alternator. 85 amps @ 12 volts is 1.02 kw. 1020 watts/746 is 1.37 hp. Single vee-belt transmission efficiency is around 90%, bringing the required power to 1.52 hp. If you add the alternator's 55% efficiency, that brings the power required to drive it to 2.76 hp. Thus the engine is overloaded and bogs down when the alternator loads it down. A 65 amp alternator would be the biggest alternator that engine could realistically handle. Nice videos. Cheers.
Interesting calculation.
Where did you get the 85A requirement?
that generator gives 100 ampere just in the beginning , thats whay the engine stalled out . when the generator is produsing for full you need a motor on 5 HP to make it work . this is just in the beginning of the charging cyckel , then the powertake out drops very fast down to 70 ampere and thats why youre engine have to work so hard in the beginning and it runs lighter and lighter the more it fills up the battery. i have built one to with a honda clone and i dont recommend you to change the pully on the motor to a bigger one becourse it will get hard to crank over to start up . best wishes from sweden 😊😊
+Håkan Andersson , thanks, I realise that now. Where are you in Sweden. I love Sweden I lived there for 3 years. I just went to jokkmokk on vacation!
Bodgemiesteri i live about 20 minuts above Karlstad
+Håkan Andersson , I've been to karlstad many times. I've been to every railroad station because I worked for banverket
Bodgemiester i got friends that work on banverket here , one is called Lars the outher one is called mateus.
+Håkan Andersson , ha small world. Subscribe to my channel and look at the BIG generator I have just made
This would be just guessing, but i think the cables can get connected first. That the resistance is not at so low rpm as when starting it😊
@Rohan Isaias well that changed the topic😂
Get a predator 420 with electric start on here . And just for fun put the a motorcycle twist throttle on the dolly then you can have fun revving it up while pushing it around
That is one option, I'll give you that
So what would happen if your battery wasn't flat? Say you just wanted to maintain the battery and subject it to a kilowatt load?
Cool Volvo. I wish we would have gotten the 3-series cars here in the US.
Close but no cigar, this is a 400 series (440xi) thanks for the comment
The 300 series was totally different, it was RWD with a transaxle, an excellent car, I grew up in the back of one. The 400 series was built at the same place in Belgium but front wheel drive and nothing like as well built but still a nice drive
I have 212 cc engine that I got at harbour freight I think it will work well. 6 1/2 to 7 hp.
Yes that is actually bigger than mine (lol implied) should work great!
*Harbor* Freight.
@@midixiewrecked7011 yes harbour freight has the predator engines. A lot of ppl modify them an use them on racing go karts
@@jamescannon4917 Harbor
@@jamescannon4917 you spelled it like a brit, there's no U in Harbor if you're a yank.
Can I make one of these with an old VW dynamo?
No reason why not, go for it!
Nice wheels 🤠
Long gone but thanks anyway!!!!
You need to do a few calcs and read up on this stuff. 100A @ 13.8 volts to charge a battery is 13.8x100=1380w, but the alternator is only about 50% efficient, so you need at least 2760w input power, and the alternator will not give full output till its spinning around 8000rpm, the single belt on small pulleys wouldn't be able to drive the 3.7BHP that is needed, that's why it won't give you what you desire. In the car its running at high speed, a step up ratio of 2.5 to 1 is usually used, and the car can do 5000rpm. A polyvee belt is usually used on these applications, they work much better than an Alpha section belt.
+Jeff Sewell , Hi, the alternator is using its original belt pulls. I had worked out the power ratings but I had this engine ‘kicking around’. Geared 1-1 it does the job I need it to you just have to let it get over the inrush. If I re power it I’ll use a 5.5bhp engine. Just a quick toy to put on UA-cam in the end
someone needs to give you a pat on the back.it is people like you,that inspire people like me,to get off my but and build something useful and get the cobwebs of of the old internet encrusted brain cells blown out. vary cool idea. i have an OLD lawnmower waiting for an alternator now . thanks.
Ha love it, I’d like to see that video!. Subscribe. I’m posting another video soon
a current limiting resistor would work to stop it stalling, something like a bulb.
Agreed, when you warm up the engine its actually fine
@@Bodgemiester I just mean for charging dead batteries, it will let you bring the voltage up from zero without stalling the engine
Yes I totally agree, it’s a great idea
@@Bodgemiester how much power you want to charge with is basically equal to the rating of the bulb so put a 120w bulb in series to limit to 10A .
i'm struggling with a 6hp diesel never mind a 2.2hp
try altering the drive ratio
If you are curious about how many RPM’s that engine can manage or till it blows just hook it up on a vehicle with 24v circuit😁😁 what if many places had such generators around, how helpfull they would be up the years. Instead we throwing functionally old lawn movers on garbage
You need to use pulleys 2:1 or 3:1(small on engine and big one on alternator)first!! and then put a regulator controller, alternatorman here in YT made one and gives pointers how to make one!!
The alternator is regulated and I have since adjusted the gearing, I actually use another battery as a capacitor and that really helps!
An alternator putting out 14vdc @ 100 amps equates to 1400 watts. 1 hp = 746 watts. Therefore, it will take just over 2 HP engine IN THEORY. But frictional losses generate heat. That takes a minimum 3.5 HP engine at full load. 3.5 x 746 = 2600+ watts. But that's not all to consider in the design. The engine spins at about 3600 RPM. The alternator needs to spin at about 2x that RPM to get full output. Double the size of the engine pulley and add a basttery and youi'll be able to crank a non-starting car engine all day long.
Since this I've down geared ot a bit. Works fine
I believe you'll need around a 180 cc (aprox 6hp) engine for that alternator & a 4 inch shive (pulley). Have look at "Knurlgnar" videos. Many Years too late.......
Ha ha, you must've read my mind. Another video on this is coming out in two weeks. I will address this issue that many have pointed out. Thanks for commenting!
Cool, i consider to mount a lawn mover engine on my trunk and alternator on inside under. If clearence to rearwindow😊 i think i choose domewhere around 5-7 hp. If i find 2 alternators i might try that since they must share on the load. Convenient i found this video. I was wondering how it would be jump starting a car like that. Alternator, water pump and power steering pump take a lot of hp from the engine. In my youth i was taking a drift on kickdown while entering an empty road. The fan belt snapped and suddenly it speeded up and i was going backwards in a inferno of tyresmoke. So now i consider suxilary engine to drive the alternator, coolant etc. 😊And worst case scenario if battery is flat is to pull the rope. But maybe i should replaced my starter engine first. 3 years ago i should. Its just that a BMW designer. Must be the worst car ever to replace a starter. If i meet that designer............
ha ha ha, it sounds like you have bigger issues
Mine is 5hp Can this power up home air conditioner
5hp will generate enough power but you need AC at either 120@60Hz or 240@50Hz. This unit is 12v DC
Bodgemiester Thanks
Bodgemiester what type of inverter need to power up AC
No problem! Please subscribe
Don’t bother, they are very inefficient, just use an AC alternator instead
Go imperial! Lol good vid man
Thanks
What are the measurement on the altinator brackets
I’m not sure, I only ‘eyeballed’ them. Nothing to fancy
A 5 hp engine is best
GM says it takes at least 3 hp to run alt if I remember correctly
I agree, I had this engine laying around though 😂
great idea how much to make one for me
@@MrGodsking no can do, sorry
A newer hairpin style denso alternator takes less torque to turn, has 12 diodes, should outlast a few generations and puts out over 2x the amperage than that old delco junk.
Probably so, but I had this and its sill alive and well 😂
damn you should of used at least a 4 hp engine.
ha you can damage the altonator with it not being connected to the battery? not good
On a modern one yes, if you do it for a long time but a few seconds won't hurt.
That tiny ground is the bottle neck, and the only reason its running at all with a load and a 1:1. Its going to overheat when you get the right ratio. no way ot can carry 100 amps! car audio people are cringing.
No it won’t do 100a continuously but it will in rush it no problem, the real issue is the ratio, it’s now 2:1 and works fine
It was struggling just trying to charge your battery. It won't provide enough current voltage to run your vehicle Sir. Rethink your idea/project.
Runs fine after inrush. Use it tonnes
12v 85 amp... It's really not loading it up much 😂😂😂 👍
Your not kidding!
@@Bodgemiester 85 amps is a good load. Congratulations
@@LU8HRW video on current limiting in the new year! Subscribe
Noooo,,,,Alternator needs to spin 2 x engine.
Agreed, then I would need a 2x bigger engine!
I can figure it out
Что-то, братец, он у тебя чахленький, еле дышит.
first
LOL