Generator is stalling
Our generator is stalling out after about 30 minutes. It is skipping also. I had inadvertantly run it with SAE 30 non-detergent for about 30 minutes, then turned it off and changed it to SAE 30 heavy duty.
Electrical Supplies - Coleman - Powermate Premium Plus 6250W Portable Generator
Answers & Comments
My answer:
Not knowing your model # and how old your generator really is - as related to TOTAL RUN HOURS - I can only give you several possibilities of what the problem might be even though I don't know the make & model and what the rated WATTAGE output is.
I also don't know what LOAD you are putting on the Genset or at what RPM you are running the engine at as to half throttle or full throttle setting?? I take it that it's a Briggs & Stratton 4-stroke single cyl, or is it a Honda 4-stroke single/twin cyl engine?
Since it runs good for 30 mins, and then starts to cut out - I doubt that the OIL is a problem even though you ran straight 30 weight - seeings most small engines run 10-30 weight oil as a rule.
I seriously doubt you did any damage to the engine at all unless it was ran low on oil - in which case it should have a LOW OIL cutoff switch mounted in the lower engine case close to the CHECK OIL port.
If the LOW OIL switch is working properly and adjusted properly then you shouldn't be getting cutout unless this switch is mis-adjusted. (ie: mechanically set too low as then when the oil level is indeed at it's proper level the switch would be already shorting out to ground) (See your operators manual for proper setting)
A way to check for proper operation is to temporarily disconnect the (usually) BLACK wire from the LOW OIL switch when the engine starts to cut out. If the problem goes away completely then the LOW OIL switch is either mis-adjusted or else it is going bad from vibration. (Again see your operators manual for proper adjustment and/or check out procedure)
Electronically this LOW OIL switch should be the only thing that would protect the engine from damage should the oil level fall below recommended level. Other then that it may have an electronic REV LIMITER if it's a bigger and more expensive model, but usually not.
I doubt the Maintenance-free Magnetron® electronic ignition is at fault, but could be weak and going bad. Always a possibility, but I would 1st rule out everything else first. Since the Genset runs for 30 mins and then starts to cut out I would look more for like a fuel vapor lock (partially closed or clogged gas cap vent), a possible dirty fuel filter, possible water moisture in the gas tank or in the carb bowl, possibly dirty carb in general along with it's dirty Float Bowl, Float Pin, Float and Needle Valve, and any Adjustment Screws that go Into the Carb Body. That covers everything from a fuel standpoint.
You do know that all Gensets should be started and run for at least 10 mins every 30 days - right? If you didn't know this - now you do! Every good operators manual should state this.
It just doesn't sound like it's starving for gas unless it's building up a (vacuum) or vapor lock in the gas tank.
Having covered everything from an Electronics/electrical standpoint engine wise - there is only one other thing left Genset wise.
What it really sounds like to me (and I personally HAVE SEEN this happen myself firsthand) is that the generator brushes are nearly shot - as in almost worn out. They may be getting too too hot - as from excessive current draw at point of contact, and thus the generator sensing circuitry itself is doing an electrical CUTOUT!!
An added protective Genset circuit feature in that the generator itself may indeed be linked to the engine as a type of REV LIMITER on the Maintenance-free Magnetron® electronic ignition. Again - your operators or service manual should have a pretty good troubleshooting section in it unless you don't have that anymore or never got one if you bought it used to begin with.
It has to be one of the scenarios listed above.
Please post me a reply as to the found problem there, and the resolve to it by following my recommendations above. Also please rate my troubleshooting fix as well.
Best regards and thanks,
Frank
Hi Mike,
Thanks for the feedback on the Genset.
Subaru engine should be pretty straight forward unless you got a bum
engine to start, but I doubt that very much, and I hope for your sake this is not the case. 30 hours
is nothing - depending on how it was broke in when brand new - all gas aside here. Again -
following the owners manual, as every engine is slightly different.
As to what you said about the gas tank, and emptying it out and then
refilling it, etc and then the problem starting right after that -
that's the KEY POINT right there!!
Now I know for sure it's Carb related as to the Float, etc.
The gas tank fuel line does have an in-line fuel filter correct? If it
doesn't you definitely need to add one for dirt protection!!
Depending on how you emptied the gas tank (tilting the Genset on end
maybe?), and what was inside it after you refilled it (as I have no
idea just how clean your gas/fuel is over there to begin with - all
water in the gas aside), you may very well have gotten either water
moisture or dirt in the Carb bowl, or else dirt in the Float Pin, Float and Needle Valve assy, or any Adjustment Screws that go Into the Carb Body.
Worse case is that you misaligned the Float itself somehow inside the
Carb Float Bowl, and now the fuel level inside is either running up too
high or else too low and causing either a TOO RICH or else TOO LEAN a
fuel mixture - thus causing the engine to maybe run way too HOT.
Hopefully the engine is not trying to seize up on you!
It's hard to say unless the Carb first is broken down, checked for
proper Float action setting, and/or cleaned out accordingly if dirt is
present in the bottom of the Float Bowl.
If all looks good there Carb Bowl wise then you will next need to check the air/fuel mixture Jet Adjustment Screws.
Let me know if you need that adjustment procedure after you first check
everything else out I sent you previously and what I sent you here
today?
Keep me posted and I'll follow up as well.
Best regards,
Frank
This is jforgette, my neighbor's generator was almost brand new, so I didn't think the worn brushes applied. But we tried the low-oil shut off idea. He thought the oil was full enough, but I told him to fill it to beginning of threads at bottom of fill hole. It only took about 1/4 cup. But... believe it or not, THIS SOLVED THE PROBLEM of dying after 20 minutes of running.
So Frank had the solution for me... thanx!!