# My friend's generator



## ToolLover (Jan 13, 2020)

Last night my friend whose wife has Alzheimer's called.
He said his utility power was off.
He said the generator was running and he had power.
Then he said he noticed that on occasion the lights flickered slightly.
This 10 KW Briggs-Stratton standby is over 25 years old.
I am thinking the commutator might need polishing and while I am at it I will check the relays in the transfer switch to see if they need burnishing.
That is going to be a trick with the power on. I may have to kill all before I take on the job.
Other than that, I will just have to poke around and see what I can find.
Maybe the spark plug needs changing?
Any ideas?
Now I have to dig up a manual on the internet to see how to get into the brush area.
Here is what I found: 
Briggs & Stratton 12KW, 10KW User Manual





Briggs & Stratton 01938-0, 01815-0 User Manual







manualmachine.com




Model 01815-0, but nothing on the brush area.


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## iowagold (Jan 22, 2020)

kinda wired but load check the battery...
it might be partial bad?
they run the fuel cut off.
and check the fuel screens etc.
do you have an o scope? you might look at the waveform.
yea check the brushes...
low hours...
but maybe dust trash? or mouse?

see if it is flickering on incandescent bulbs..
some lower cost led bulbs are not liking the gens unless they have the dim feature.
just a tip before you tear in to it.

stay safe out there!


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## iowagold (Jan 22, 2020)

oh yea check the rpm! lol!
see if it is running smooooth!


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## ToolLover (Jan 13, 2020)

@ Iowagold: I just replaced the battery and the starter solenoid last year, but I will check it.
I had not thought about rodents, but I will put that on the list to check. TY!


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## iowagold (Jan 22, 2020)

cool take your battery load tester with you...
it is on the list of things that can cause this issue.
just to make sure it did not boil out on you!
that voltage but low current thing...
it can make for high dc voltage during the run up and make it want to cycle a shut down back and forth for the un steady volts.
tricky at best!! 
lol!
been there done that one!
also look for loose or green or white connections... in plugs and screws...
dielectric grease helps on those.
pm me if you need links on that stuff.


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## ToolLover (Jan 13, 2020)

B&S model 01931-0 Twin cylinder B&S motor. SWEET!
OK, so today I got to my friends house.
I opened the cabinet and to my surprise I see no brush access.
I went round and round looking for the cover.
I am perplexed, no brush cover.
I manually start the unit and check the voltage after I realize the fluke I have does not have a hertz function.
Now I am ticked at myself for being so laxed.
I see the voltage @ 238.9 to 240.9
But then this is a slow digital meter and that could be in error.
I gave my swing meter to a now deceased friend. It is long gone. Bummer!
I am thinking I wish I had my Fluke with the hertz function.
Well, I may as well check the oil. It is OK.
I close it up and ask Bill for the book of prints I made for him and he gets it.
I come home after kicking myself for being so so so!!!
Any way the book shows this generator to be a brushless model.
Two Capacitors on the top under a protective cover and Cap diode set mounted inside the rotor.
Before I get into a tizzy about the flickering lights, I need to look elsewhere.
Bill said all lights flicker, so that lets out a bad switch.
I am looking to you guys for a solution.
How about a: bad cap? contacts in the TS in need of burnishing? Maybe something I am missing? maybe lugs need tightening?
I thought I had the brush thing covered, but now I need to rethink my attack.
@ Iowagold: I checked the battery: 14VDC at rest. Motor runs smooth as silk. No hiccup's.


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## ToolLover (Jan 13, 2020)

After spending some time talking to Paul last night, I had the prints for the B&S generator.
I told Paul that there were two large capacitors on top of the generator that I was suspicious of.
Paul told me that the caps often had a life of 8 years and I should check them.
Well, you might know the part numbers have changed from B4914GS to 311560GS.
Prices range from $49.99 to nearly $80.+ each.
So I called the owner and asked if he would be OK with my ordering the caps and have them ready when I took the top off of the generator to get to the caps.
He agreed, so the caps are on the way.
What bugs me is that the top has to be removed, then the caps are under the muffler which is above the stator housing.
The caps are inside a plastic cover that may be difficult to get off with the muffler on place.
Well, at least I found the caps: 25 microfarad @ 450 volts.
On another note:
I ordered a stand alone frequency swing meter that will allow me to view the fluctuations on frequency. $10, should arrive today.


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## ToolLover (Jan 13, 2020)

Reporting back:
Well, one thing led to another.
The caps inside the generator were 45 Micro farad, not 35 MF as the manual indicated.
I did not replace the caps as they checked OK.
It was a 2 hour job just to get to them.
I found the oil temperature switch broken and had to wait for a week for that.
This week I got back.
I had the unit ready to start.
I removed the load wiring and installed a pair of 100 watt light bulbs for a load.
Looking over the unit, I decided to start it up.
Now, you must know this started because Bill (the owner) said his lights were blinking.
I had talked to Paul about this on the phone.
So I started it. It came to life, and I looked at the light bulbs. Nothing!
I put the frequency meter on it: 60 to 75 hertz. Voltage: 4.5 VAC.
The I hear the loud cheerp, really loud.
I move to look inside the cabinet and again the cheerp, along with bright sparks coming from the housing behind the flywheel which Bill mentioned seeing before.
Paul and I had discussed the cheerp which I had heard previously.
Paul said from his experience the loud screeching or cheerp indicated that the stator was grounded.
Paul had looked at the prints and this B&S was a brushless unit.
Well, now I had concerns of my own. Maybe the flywheel was involved in the sparking.
Paul pretty well put that idea to rest with a good experienced explanation.
Paul surmised the the problem began when the lights first flickered.
The problem escalated from a broken connection of a diode in the stator (causing the flickering) to it breaking loose and shorting out (causing the sparks). Good! Paul knows his stuff.
This then sent the voltage being generated through the stator shaft, thru the engine crank shaft to the flywheel.
The sparks I saw were the end result of the voltage discharging and causing the loud cheerp.
He said he had experienced this at other times on generators.
So, here I am, disappointed with my effort to fix what I though was a minor problem.
I am too old to struggle with pulling the stator plus the fact that this is a 25 year old B&S generator.
Might as well say it is the end of it's life.
Bill looks after his wife who has Alzheimer's and is tied to the house 24/7.
In our area there is only one generator repair company......Generac is their brand, so Bill is in a fix.
He is set on using the local company as they offer good service and they have 2 14KW's in stock along with new TS's.
Now, I have got to decide what I am going to do with that failed B&S.
The parts are out of production and I may break it down and offer them to buyers.


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## ToolLover (Jan 13, 2020)

Update: The company did not want to install the 14 KW because the copper gas line is too small to provide the necessary amount of gas to run the 14 KW.
They found a 10 KW and that is fine with Bill.
Looks like we are set to go.


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## Airstreamer67 (Oct 3, 2020)

ToolLover, you deserve a medal helping the neighbor with a 25-year-old genset. Good for you!

I believe it's the better part of valor for him to just replace it, as is the plan now. Fixing it seems to be a poor choice money-wise and time-wise and save-your-sanity-wise.

I've still got a 25-year-old unit that continues to operate. I recently found that a solenoid designed to hold the throttle open is not operating for one reason or another. I don't know if the problem is the solenoid itself, which is a $100 item and the maker, Trombetta, can't even exactly match the numbers on it and would have to guess at what replaces it, or if it's an electrical control problem somewhere.

In either case, I simply am using a rope to hold open the throttle, which results in the requisite 3600RPM operation. The only real disadvantage to doing this hillbilly procedure as far as I can see is that should the low-oil-pressure sensor detect low oil pressure, the unit will continue to run to destruction because there is no longer a solenoid to shut down because my rope is holding the throttle open.

Oh well, after 25 years of service, I'm not sure how much I should try to fix it. At present, I'm operating my faithful old genset without the low-oil-pressure protection. Maybe I'll get around to fixing it. Maybe I'll continue using it like it is. I'd be motivated to try harder to fix it with a newer unit.

If it blows up, I'll be taking a page from your neighbor's plan book.


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## ToolLover (Jan 13, 2020)

@Airstreamer67: You did not mention the name and specifics of you genny.
You never know but there might be a solution hiding in someone's knowledge base about where to find the needed part to solve your problem.
I am sure you have searched without success, but give us a chance to help.
Have you determined the voltage that holds the solenoid up?
Detecting that will tell you if the solenoid is bad or lacks the control voltage, which I am sure you know, but you gotta start somewhere.
As to replacing Bill's generator, it is going to be expensive.
Bill only had a 1/2" copper line feeding NG to his unit.
Installing anything bigger than the 10 KW was going to present a big problem getting a bigger pipe for supply.
I am really surprised how much generators have increased in price in the last couple of years.
Best look after yours as a new one is outrageous.


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## iowagold (Jan 22, 2020)

looks like prices are on the way up again!
some is the demand for the gen sets...
but most of it is the parts and costs to get the stuff...
i have had 5 more items this weekend that are 6 months out...
BIG back orders!
so stock up on the things you need...
oil, spark plugs, filters etc...
things could get worse!
my plan has me covered for 2 years on the parts stock for my gear here...


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## Airstreamer67 (Oct 3, 2020)

ToolLover, thanks for the interest! I haven't checked what's wrong with my genset past finding out that Trombetta doesn't have the solenoid number in their database anymore because it's too old. That is understandable for 25-year-old stuff. It's also a good argument for just buying cheap use-and-discard stuff rather than buying last-forever-with-care stuff. I've historically done the latter, but times they are a'changing.

I'll pursue this project sooner-or-later when I get in the mood and will see if anybody here has experience with my unit: a Yanmar L100 diesel engine with a 6000W Gillette generator head. It was bought in 1995 and has served me well through the years. Indeed, it continues to operate even with my Rube Goldberg throttle-controlling rope. 

The Yanmar is very fuel-efficient, and I will keep it running as long as it makes economic sense to do so.

To replace it would cost maybe $4K or so. 

I paid $2200 for it in 1995, so the capital cost has only been about $85 per annum so far. Not bad. I'll try to whittle that $-per-year down as low as I can. I have a good chance to do that with this year's fast-approaching hurricane season, unfortunately. 

Hope your neighbor's new unit works out OK. A 10,000W unit should serve him well. I'd get a natural gas unit myself if I had natural gas. c'est la vie.


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## ToolLover (Jan 13, 2020)

Give us the serial number and model number please.


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## iowagold (Jan 22, 2020)

and snap some pix air!
I bet I can find one!
diesel stuff is not that hard to find parts for....
lol
but with that said... this parts from china thing is getting worse!
lots of parts are drying up due to the mfg plants over there shutting down last summer!
I have more parts than some of my suppliers right now!
no kidding!
you know it is bad when the guys you purchased the parts from cold call you and ask if you have any of the parts!
I had 3 of those calls this last weekend again!

snap some pix, take some measurements of the stroke etc.
I have lots of them here...
and places where you can purchase them from as well.


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## ToolLover (Jan 13, 2020)

Bad news for Bill, the quote to change out was 10 KW for another 10 KW was $9700.00.
Bill balked.
I guess I will get to do the deed.


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## ToolLover (Jan 13, 2020)

Well, Bill got frustrated with finding a 10 KW Generac.
He decided to go with the Contractor as the price was lowered $500.
Now Bill has offered me the B&S.
He said take what you want.
I really do not have a need for any of it.
I can part it out if any of you want any of it.
The twin cylinder motor runs like it should.
The TS is good and there are two cards and a few other items.
So let me know and I will get things going.
I will go there tomorrow and disconnect it from the gas and electrics.


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