Small Engine Problems? Ask an Engine Mechanic for Answers ASAP
The serial # XXXXX(NNN) NNN-NNNN There is no model number listed. I brought up schematic diagrams up for a Centurion and it seems to be close.
It says Generac Guardian 15000 on one sticker, and on the other sticker which is located on the panel with the recpticles it says Industrial/commercial 15000 watt.
I thought it was a spark problem. I went through the print and everything checks out. I now have spark. The engine starts and stalls immediately. I had gas in it about a year. I drained the fuel, Replaced with new fuel, replaced thefuel lines. It has a plastic fuel pump on the valve cover. It seems to be pumping fuel in sperts.I think it is ok but not shure if it is putting enough pressure. I pulled the carb off and blew air through ports they seem clear, the govener seems like it is working it opens and closes the throttle.
As gas gets old, it turns to varnish and clogs up the passageways inside the carburetor, not allowing enough gas to get to the engine.
This condition is cumulative. Every time gas sits, the varnish builds up just a little more, like coats of paint, until eventually gas can not flow. It will not happen overnight, but the symptoms can show up all of a sudden, even while simply stopping to refill with gas.
The use of fuel additives, such as Sta-Bil or Sea Foam will not stop this process from happening. They will greatly slow it down, but the gas will still go bad.
When this happens, either the engine simply will not start, or it will not run without the choke on (this reduces the amount of air getting pulled into the engine, changing the fuel/air mixture), or it will run but surges.
Another issue that varnish in the carb can cause is that the varnish may not allow the float needle to seal properly against the seat, causing the flow of gas to not shut off when the bowl is full. The result will be gas overflowing the carb and running into the cylinder, and possibly out the air intake. If the gas gets into the cylinder, it will seep past the rings and down into the crankcase. This will be evidenced by your oil level being over-full and/or the oil smelling like gas.
If this is the case, you will need to change the oil and filter, if it has a filter.
The only 2 solutions are to either replace the carburetor or give it a good, thorough cleaning.
When removing the carb, make sure to take a good picture, or make a good drawing of where all springs and linkages are attached. This will make reassembly much easier.
Most people believe that cleaning a carb involves removing the bowl and wiping it out, then spraying some carb cleaner through it.
This is simply insufficient. It takes months or years for this accumulation to build up – it just can not be removed in minutes.
To properly clean the carb, you must remove it, disassemble it (making sure to remove all non-metal parts), and soak it in a commercial solvent for several hours. Soaking it overnight is even better.
Then clean all solvent off with a spray type carb cleaner, making sure to get lots of cleaner into every hole and passage there is. Pay special attention to the tiny holes in the bore of the carb, under the throttle plate for the carbs that have these holes. Use lots of cleaner. And make sure to wear safety goggles to avoid getting the over spray into your eyes. There will be over spray.
Dry the carb with low pressure compressed air.
This is an EPA compliant carburetor, and as such, is not supposed to be taken apart or adjusted.
When you have an issue with it, you are supposed to replace the entire carb.
But, sometimes it is possible to clean them. Just remember, that as an EPA compliant carb, there are no parts available for it, so if you lose or break anything, you will definitely need to get a new one.
Occasionally, even a good cleaning is not going to be sufficient, and you may end up having to replace the carb anyhow. Be prepared for this.
If for some odd reason this does not help, please let me know so I can assist you further.
I lost spark. I pulled wire off oil safety switch unit does not have spark. I checked oil switch with ohmmeter it is supposed to be normally closed, it is. when I crank engine it opens when it sences oil pressure which leads me to believe it is ok. I pulled off wire comming from coils measured voltage about 1.5 volts dc. Carberator was opened seems clear sprayed with carb cleaner and blew compressed air through ports seem clear. where does spark get generated from? does govener control spark?generator always ran good, Just one day did not start. I removed gas put in my car and had no problem with it. carberator had no varnish in it that i could see. Thanks for the help.
No spark. Plugs are wet pulled plugs blew them out with compressed air. They are new. Grounded plug cranked engine no spark.
I removed the magnetos checked them with a ohmmeter and they read 18000 ohms. I cleaned a minute amount of rust and dirt off the flywheel removed the diode harness, Reinstalled the magnetos and the engine now fires up. I reconnected the diode harness and the engine does not start. disconnected the harness and the engine fires. It seems to run full out no control. I am getting popping from carberator I am figuring without diodes no govener control and i guess the popping is timing is off. I checked diodes with incorrect polarity shows open circuit which is what you would expect. with correct polarity it shows 2.2 meg ohms on one and a little higher on the other. with good diodes installed will the govener control return and the popping stop or do you think i have to look elsewhere?
It is racing actually running at 78 Hertz instead of 60 .
I have corrected the spark issue thanks to you, However i also have a carberator problem. I tried to clean it as you have stated earlier but it still does not work. I am trying to find a carberator but my old Generac Part # is 0C8526 and cannot find a repalcement # everytime I punch in the # the part does not come up.