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Hi Mark

Well it certainly was an interesting thread to say the least. There is just something cool about a generator. Right now it's about 23 F. outside and still snowing. Nice to know if power fails that I have a generator and worst case if that fails I have a back up to the back up. Ever since I was a small kid I had this fascination with generators as well as motors, the old "How does it do that"?

Glad you finally have something fruitful after all the work...

Ron
 
For me it's the portability of the power. And the engines are so simple - OK, WERE so simple. That little bugger just bangin' along spinning a bunch of wires and out comes electricity. As you said, it's just cool. A lot of that feeling carries into my motorcycling. I'm tempted to go backward to the simple days of cycling - back to the low tech days. I'm at the IX Center for the motorcycle show each year.

Now I need to revise my documentation to reflect the Coleman PowerMate generator. The wiring diagram needs a little revision. I need new photos. And I need to do a stress test so I can advertise what output I've actually seen rather than just the claimed power. I had 12 amps at 127 volts today. After 10 minutes at 6 amps I bumped it up to 12 amps just to see what it did. I'd guess that a full 20 amp load will pull the voltage down to 115vac but the governor holds to within 5% of the required 3600 rpm.
I'd like to find another $30 generator head to mate to a Chinese Lifan engine (the Honda Clone) just to mess with.
So this is done until I pick up another old genny and get stumped. What a ride.
 
Hi Soloboss,

Ive been following this thread with its ups and downs.
Glad you now have a working unit.
Best of luck with it,

John :)
 
It sure didn't end like I wanted it to. I wanted to end up with a nice looking and good running Ag Tronic. As it is, I guess there's little doubt that I did all that I could do to ensure it wasn't repairable. No way will I pay for a rewind on a generator that is not collectible. As it sits, it's probably as good as it's going to get. Repair parts will be Powermate or Briggs and Stratton. And it does run really well.
Thanks for the interest! This has been a fun ride and you guys are really helpful. VERY much appreciated.
 
Generator Success!!

Gents - The old Ag Tronics engine is now spinning a later model Powermate Generator head. With the totally reworked generator working wonderfully, I now have a new question.
My dad wants the generator as a backup. He wanted to run a couple of lights so he and mom could play cards while they waited for the power to come back on. Then he wanted a refrigerator to run too. So far, no problem. Now he wants the furnace to run too. Hmmm. Digital thermostat. I don't know about that. And he wants the flat panel television also.
I can put a 4000 watt generator at his place but he's keeping this on the cheap so it'll be the older brushed type generator. There are two ways to determine what's going to happen when I plug him into the generator. The first is to just try it. I'll certainly have an answer pronto. But we may not like the results with the TV and the digital thermostats. The generator voltage is stable at 117 - 123v depending on the load. The frequency is 59.5hz - 60.5hz. I don't have a scope so I don't know what the condition of the sine wave is. I'm looking for a reasonable test. I've heard that simple computer backup power supplies are fairly fussy about their power - too dirty and they won't operate. I could try that on the assumption that the TV will work if the UPS works. I could plug in a CRT TV and if the picture is decent it should be OK. Are those valid tests? Got a better idea? He won't buy a UPS to condition the power for the television.
If you're thinkin', I'm listenin'. Here's a photo of the finished generator project.
Mark
 

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The only thing I think you could have a problem with is a timer that relies on the mains frequency as a reference in which case, nothing bad will happen, it just won't keep good time..

Most modern electroincs should be fine because the use SMPSes which ware regulated and can work from a wide range of voltages. AC motors such as the type found in a fridge need a sinusoidal waveform to work which won't be a problem because it's what the generator will produce.
 
Before I forget, great picture. Came out really looking great!

I can share my own experiences with you using a 4 KW Powermate (5 KW Surge). My initial experiences were with that Powermate. I initially bought it when my wife's mom was alive and 100% bedridden. More and more support equipment was moving in as she became worse. I went with the 4 KW unit as I wanted a generator with 240 VAC out to make connecting to the house mains easy. Even though it was a manual process, I needed to make the change over simple so the wife, her brother or her older dad could do the task.

That little unit did fine and would run the gas forced air furnace blower motor, all basic lighting and appliances including two refridgerators and a large freezer. Consider that refridgerators, freezers and a furnace only run on demand and with any luck won't all demand power at the same time. As long as during a power outage users don't needlessy open refridgerator doors they don't really cycle much at all. When the furnace blower motor would kick on there was a slight drop in RPM the instant the load was applied but that dip was very quick and hurt nothing.

Looking at the generator output on a scope really isn't too revealing. Figure a 120 VAC RMS sine wave will yield a 340 Volt Pk to Pk sine wave you really won't see much low level noise or distortion riding on the peaks and valleys. To get fancy you need a good power analyzer and I never bothered.

You could go from item to item and add up the individual power demands for a rough idea of everything he wants running.

If I had it to do again I would have gotten a unit with a larger fuel tank. I think it has a 1.5 US Gallon tank and during long outages required fueling more than I liked. I was going to get a larger tank but the wife's mom passed away so I never bothered.

The then TV ran fine on it, it was an old big screen Magnavox.

Today it has all been replaced with a natural gas unit and full automatic transfer. Everything I have concerns with has UPS backup including the new TV a large flat panel Sony. The TV even runs fine on the UPS which produces an ugly modified square wave. The UPS units only need to support their loads for about 8 seconds as within 10 seconds transfer to the new generator happens.

Overall those little Powermates do a good job. The old 4 KW unit sits in our shed and that unit has helped neighbors countless times during outages. Looking back I bet I got that thing 15 years ago. :)

Ron
 
You're right here for me again, guys. Thanks. The folks balked at getting the new TV's but now that the new sets are in service I sure didn't want to fry a new television by using a generator. I was looking for a gut feel about hooking new electronic stuff to an old generator. 12 years old. That's like - 1998. Is that old?
I included a photo of the unit that is going to Dad's. It runs a LOT quieter than the Powermate and it has a 4 gallon gas tank. It's a 4kw Generac/Tecumseh 8hp unit. I believe it's a full wave rectifier like my 2.4kw Generac - and it's certainly brushed. I expect that it's easily the equivalent of a Powermate as far as waveform quality. I don't know if the 4kw rating is max or running output but they live pretty simply and they understand emergency situations so they'll keep the power load down.
I read somewhere that they want to get the unit fully warmed up and then load it with a constant load so it's stable before they turn on televisions and sensitive stuff. Probably turning on the furnace blower to RUN so it's constant will stabilize the generator. I'd like to see them use a UPS but that's not gonna happen.
Any more advice is welcome. Thanks for the comment on the Powermate project!
 

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I would venture a guess that the 4 KW rating is the output with a surge rating around 5 KW for short periods like when a motor starts. Nice is where I originally screwed up with fuel tank capacity. Four gallons should keep it running for several hours and much more under lighter loads.

Don't know if it holds true on this unit but Sears is good about online manuals so with an exact part/model number you can likely get a manual.

Additionally guessing from the image it looks to have a 240 VAC outlet which makes for cool if you want to set up a pony point where it can be directly connected to the mains supporting the house. Obviously not connecting directly into the mains! But a system to allow the unit to be dragged out and connected once the mains breakers have been turned off and back feed into the main circuit breaker panel through breakers.

As to age? More a matter of actual runtime. A ten or twelve year old unit with little run time in hours is as good as a new unit. You saw from your initial project that the guts don't change much. A unit with lower runtime that has seen good maintenance (regular lube, oil and filter with good quality oil) should perform every bit as well as a new unit.

It's nice to have the security of power during a power outage, especially in the cold of winters.

Ron
 
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On the old B&S engines you can expect about 1500 - 2000 running hours if they are maintained properly and not ran at heavy overloads for long periods of time.

As far as what the power looks like that comes off of one of those older style generators its probably cleaner than what your utility line power is some days.

Generator age wise I have a early 1950's Fairbanks Morse 3 KW that still powers everything I need. I ran it for 12 hours a day for almost a month non stop when I started building my place out in the country about 10 years ago. It powered the saws and kept the lights on while I was working until the utility company got my service installed.
 
I would venture a guess that the 4 KW rating is the output with a surge rating around 5 KW for short periods like when a motor starts. Nice is where I originally screwed up with fuel tank capacity. Four gallons should keep it running for several hours and much more under lighter loads.

Don't know if it holds true on this unit but Sears is good about online manuals so with an exact part/model number you can likely get a manual.

Additionally guessing from the image it looks to have a 240 VAC outlet which makes for cool if you want to set up a pony point where it can be directly connected to the mains supporting the house. Obviously not connecting directly into the mains! But a system to allow the unit to be dragged out and connected once the mains breakers have been turned off and back feed into the main circuit breaker panel through breakers.

As to age? More a matter of actual runtime. A ten or twelve year old unit with little run time in hours is as good as a new unit. You saw from your initial project that the guts don't change much. A unit with lower runtime that has seen good maintenance (regular lube, oil and filter with good quality oil) should perform every bit as well as a new unit.

It's nice to have the security of power during a power outage, especially in the cold of winters.

Ron

Ya really think it might be a 4k with a heavier surge? Thinking about it, that may be. I have a 2.4k generac and this 4kw is easily twice the size. Sounds reasonable. And the 8 hp engine supports the idea that it is a 4kw constant output.
Fuel Tank - the larger tank size was a selling point. And the large fill opening is way better than trying to pour gas into the small tank under the air filter. So far I've had no luck finding a manual. I do have the model number but the Sears site isn't connecting it to anything.
It does have a 20A duplex, a 3 blade 120v for boats and RV's and a 4 blade 240. Another good selling feature.
I've found a cool interlock kit to allow us to add a pair of breakers in the main box, with a 4 conductor cable permanently attached. Connection would involve only running the cable to the generator and the box-interlock will prevent the new breakers from being switched ON while the mains are ON. Here's the deal - **broken link removed** So simple and it addresses the issue.
I purchased this unit from a fellow who got it from an estate auction at his neighbor's house. He figures about 5 hours run time bu tit probably sat unused for an extended period. The wheels do have a significant flatspot, indicating a long storage on a hard floor. He recalls only one significant instance of power outage when the generator would have been in use. The air filter is original and is off-color but looks OK. He put clean oil in it and I just changed it again - along with a new air filter so it will be delivered ready to run. Other than pulling brushes I'm not sure how to determine the actual runtime. Pull rope is good, vibration bumpers aren't checked, general condition shows in the photo.
It starts on the second pull - ALWAYS! It has a large shoebox size muffler and the output is very stable. I got it for $225 - and a 150 mile round trip to get it. But it doesn't have a low oil shut down. Bummer. If it doesn't use oil that's not a big deal.
Mark
 
On the old B&S engines you can expect about 1500 - 2000 running hours if they are maintained properly and not ran at heavy overloads for long periods of time.

As far as what the power looks like that comes off of one of those older style generators its probably cleaner than what your utility line power is some days.

Generator age wise I have a early 1950's Fairbanks Morse 3 KW that still powers everything I need. I ran it for 12 hours a day for almost a month non stop when I started building my place out in the country about 10 years ago. It powered the saws and kept the lights on while I was working until the utility company got my service installed.

tcmtech - This is a Tecumseh 8 horse. What are your thoughts about those? I've heard of concerns about being able to get a stable engine speed, but the governor is rock steady on this one.
So, the output of an older brushed genny is really that good? So, why do I read that anyone with modern electronics should ONLY use a modern brushless system. The Onan site says that the brushed systems require a bit more maintenance but they are very clean and stable. Sounds like the recommendation to only use a brushless is a sales pitch. I'm not hearing anything that indicates I made a bad purchase. Makes me feel better. I have a lot of confidence in the knowledge base of this forum.
Thanks - Mark
 
I have never had any problems with Tecumseh engines. Being yours generator starts on the second pull it had me thinking that it couldn't possibly be a B&S!

I have always known the B&S to stand for "Battle & Struggle" when it comes to starting them.:p

If your Tecumseh is one of the older cast iron sleeved H80 model engines it could likely outlast a B&S. They where well built but the governor linkage is what typically causes unstable governor problems. The linkage wire needs to fit tight at the pivot points and the spring has to be set in the exact right location or they tend to surge and hunt.

One thing to consider is if you can ever find the electronic ignition coil from a newer model at a fair price its worth switching it over from the old points style ignition. The old points type ignitions are hard to work on since everything is under the flywheel plus they seem to have a tendency for slight timing drift problems as they get more running hours on them.

I never cared for their recoil clutch mechanisms though. They always seem to break at some point in time. But they have a far superior carburetor design over the B&S engines which makes them far better for cold weather starting and running.
 
The only thing I would add is that is wise to occasionally "exercise" the generator. Let it run a little. I also once a year on the unit in the shed allow the fuel tank to run empty and dump and clean the bowl on the carbuerator.

I keep about 15 gallons of fuel stored in the shed and maintain it with Stabil. I don't know for sure that it helps but it sure as hell doesn't hurt. Once a year I dump that fuel in my truck and replace it. Generally I do all that in the late Fall season.

Good handle on transfer so that is cool.

Funny Story:

Several years ago in September a severe storm ripped through Ohio. We never lost power in my area of Cleveland but my 90 year old mother lost power in Columbus, Ohio. At 90 my mom still lives in "The Big House" on her own. My brother called telling me that mom was without power and it would likely be 3 days before power was restored. My brother looked locally for a generator and discovered there was not a unit to be had between Cincinnati and Cleveland. Everyplace was simply sold out of stock for small portable units. I told Russ if he drove up here he could have my spare. Hell I wasn't worried with my big unit.

Russ drove up in the few hours it takes and had question after question as to how to connect it. Unfortunately only I have my father's genes. Russ is a college professor of the arts. Forget technically savy. OK, we put the generator in my truck and drove to Columbus in tandem. We had mom's house up and running in 30 min.

Within about an hour the phone rings and someone was complaining about the noise. They said they had someone ill and the noise was disturbing them. This noise amounted to a loud lawn mower. I very politely pointed out I was sorry they had someone ill but I was not about to relocate my 90 year old mother and I would shut down the generator at about 8 PM. She was quick to point out her husband was an attorney so I pointed out I was a high power rifle enthusiast and enjoyed shooting in competition, I added if she had a problem she should call the Worthington, OH. police department.

Sure as hell the police show up. We were just fine. He did ask if I mentioned High Power Rifle Competion and I said yes I did after she mentioned attorney. The officer was also a rifle enthusiast so we got along fine. I showed him mom's freezer and pointed out that the generator during waking hours was about like a loud lawnmower. He agreed. The power was out for 4 days and for 4 days mom had power during the day and her fridge and freezer ran just fine, as well as lights and TV.

Gotta love the security!

Ron
 
I had to laugh at your governor comments. I looked at the governor linkage and my thought was that it looks like something I'd come up with out of my junk bin. Looks like something that was a field fix for a one-time use. Sounds like as long as all the springs are on and the linkage is free of slop it should run OK. I have no experience with Tecumseh other than this one. One gentle pull with full choke, then a gentle pull with no choke and I get a half hearted PUTT . . . PUTT . . .long pause . . Putt - and then it picks right up. If it didn't have the heavy rotor it would be a bugger I'll bet.
Mark
 
Great story Ron! People aren't willing to cut a little slack even when there's an emergency situation. Playing your 90 year-old-living -alone mom against her the lady's husband makes that a wash. And a time split is reasonable. We have a noise ordinance in Fort Wayne, IN - it's a 9am - 7pm thing for power equipment. But for emergency situations the noise ordinance is suspended. Again, reasonable. They say the best way to quiet these folks it so take them the business end of an extension cord full of power. With doors closed, my neighbors can 't hear my 5000/6250 watt Guardian unit. Glad the police were agreeable.
I read on a generator manufacturer's site (Onan I think) that they want the generator run monthly, loaded at half the output capacity, for a full half hour. That heats the generator head and dries the moisture out of it. Of course the engine likes it because it lubes the seals and the engine stays tighter longer. I hadn't thought about significantly loading the generator but that sounds logical. I've just put a little load on it so it was stable. I'll change my practice and run more often and run longer with a load. I guess that's free heat in the winter! And that engine warms my shed up nicely.
Mark
 
My 18 KW unit runs for 30 min once a week which keeps the battery up. I can change that but it works for me. About once a month (give or take when I think about it) I wander down the basement and simply turn the mains off. That starts the generator but also allows it to run under a load. The exercise cycle does not allow for a load, it simply runs. There is no transfer.

Yeah, Worthington, Ohio is a trip unto itself. My parents moved there in 1965 and my mom is one of the most senior seniors in the community. When mom & dad moved there it was average middle class with their home costing about 35 to 40 K. Today many of those 5 bedroom colonials are 500K plus homes occupied by doctors, lawyers and OSU staff in well paid positions. The place is a wonderful breeding ground for arrogance and snobs who I have little use for or patience for. Mom's property taxes are about $100 a week or $5,200 a year and for that she gets little but great police protection.

I just got annoyed when the caller was so quick to point out her husband was an attorney. Like I should care?

Gee, you would think in such a well to do community that they would all have power backup? I guess not. I think it was more a matter of envy as when things hit the fan, my mom's house was supported. Funny as after the call my mom and brother were ready to turn it off (remember the arts?) I was like no way in hell! Artist are so easily intimidated and wimps. :)

Ron
 
Ron, I wish we were neighbors. We do think alike. In fact, I'm thinking we're not alone in this forum. That snobby crowd is laughable unless we have to live around them. Where I am we're all just folks. And if I get into a situation where power goes down again, I'll be able to drop a light line to a couple of neighbors. I paid my dues last year and I'm keeping the big cord for my house!
In my parent's case, they are also the senior amongst the seniors around the lake. Dad purchased 4 lake lots a number of years ago. One had a house on it and that got restored and sold. Two of the other three lots had what could technically be called cottages on them but mostly they were just tiny shacks made of rotten wood. One came down and the other became - OK, story time.
Dad wanted to build but the cost was horrible. A "room addition" was in order. He got a permit to rehab the larger of the two shacks. So he added a "room addition" to the north side of the shack. Then, using the same building permit, he added another "addition" to the east side. Then the west side and finally the south side. Then he added a basement under the west side and eventually he had built a whole new house around the shack. One wall of the family room has the original breaker box still in the wall that was the front wall of the shack so he can prove he has a renovation and room addition. 2800 square feet of room addition. Ya just gotta love it.
And my folks will be amongst the very few who will have back up power. Go figure. The good part is that the new generator has a large muffler with a small outlet and it looks at a ravine in the woods. No problem there.
$100 a week in taxes? That's just wrong. OK, if it's populated by snobs and artsy folks, they deserve it. But your mom should get the Senior Mom Discount.
 
Thanks for sharing a great story as we drift off topic but what the hell, it's a great thread. You are fortunate as you still have both parents.

Yeah, Worthington is a trip of a prestegious little town North of Columbus, Ohio. I guess what pisses me off is that Kathy and I live in Bedford Heights, Ohio a Cleveland suburb. We pay less than half of what my mom pays in taxes but seniors here get lawn mowing in the summer and snow removal in the winter. This small city is a great deal for seniors and those who have been here forever get a tax break.

Fortunately my dad left my mom well set but she is also backed by her "brood" of four of us. There is nothing that any of us would not do for her. When my dad was dying the neighbors were amazed at how the four of us traveled to be home every weekend to support our mother. Gee, immagine that?

Treasure your parents and be greatful for all their sacrifice having you and any siblings you may have. There will never come the day you can't do enough for them. There will come the day when they aren't around for you to do for them so do while life is good. :)

Yeah, we also have long extension cords. Been there and done that. I was born and raised till about 16 in NYC. Today I live on a small street with real neighbors. My wife grew up on this street in this house. Hell, she babysat those who are now neighbors on this littel street. It's like a littel friggin Americana. My neighbor Cal plows snow. Funny how my drive is always plowed and he won't take a dime but we recently rewired most of his house and I wouldn't take a dime. The people of Worthington could learn a lot from this place. Quite a lot.

Ron
 
That attitude shows in this thread. Likely it shows all through this forum. I was heavily involved in an RC Helicopter forum a couple of years ago and the results were similar with lots of good folks doing all they could do to share information and in many cases, share parts with guys who had a need. OK - one more quick story.
One post in the helicopter forum was from a combat helicopter pilot in Iraq. In his off time he played with RC helicopters in his portable housing unit. He contacted the forum asking our advice about what his next step should be as he had mastered the little bugger he was flying. Since several of us were regulars and the owner of a Hobby Shop in the Washington DC area was also a major player in the forum, I asked if anyone might be interested in supporting our flying soldier?? He'd tell us what he needed and we'd supply the parts as a little "Thank You". We're talking about $20 on occasion as he needed parts. I simply asked the question. Twenty minutes later I had agreed to handle the donations and coordinate the project with the owner of the hobby shop. He volunteered to discount parts and handle shipping. In 12 hours I had $200 donated. In 24 hours I had nearly $600. The first thousand dollars came in less than a week. Before our soldier had returned home, we had shipped more than $2000 in new RC helicopters and parts to the other fliers in his unit. The guys were pretty touched by it all. Several of the guys in the forum made life-long friendships with our soldiers when they returned home. Forum folks are different. We're here because we want to be and it's pretty special.
I like it when a plan works. Be true to who you are and you'll get what you deserve.
All the best,
Mark
 
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