Those w/ Generac stanby generators....quick ?

[General Lee]

I have a 20KW, recently installed. I have noticed during exercise mode it sounds as if the exhaust or motor has a small miss. It runs at a lower RPM during exercise mode (normal) The miss, (slight popping sound) is really only heard up close to the unit. The further you are away you can't hear it. And the miss is only every few seconds.

Is this evident on any of your units? Is it normal? I was thinking it may be the governor doing its thing to control the RPM's. Trying to decide if I need someone to come out and take a look.

 

[mfreund]

I have a 20kw on propane. I have not noticed any type of miss. Ours also runs at full throttle when in exercise mode. I wonder if yours is set properly for the fuel being used. If you take off the air cleaner there is a rod in the middle of the carburator that needs moved for propane use. It comes from the factory set for Natural Gas.

It is the best money I have ever spent

 

[dschuffert]

I have two 20KW units that run on propane. I run them at a lower rpm in exercise mode. I do not notice any type of miss. I installed mine in April of this year and exercise them on a weekly basis on Saturday mornings. I just installed the cold weather kit in each one this weekend. I ran them in manual mode for a few minutes to make sure everything was still working after I installed the kit.

As mfreund stated you may want to check to make sure the fuel type selection is properly set. You may also want to check and test weather you are getting proper gas flow as described in the manual.

 

[kiotiken]

I have a 16KW unit and it runs a lower RPM while exercising. I notice the exact same thing you do. It's been doing it since new, which was several years ago now. It's never missed a beat when needed.

 

[Toyboy]

I have the 20kw and have the pop in the exhaust from time to time when in exercise mode also. Mine is running NG. To me it seems like it may not be burning cleanly and sending some unburned gas into exhaust. Maybe it's because it's running at a slower RPM??

 

[BuzzardA91]

I have the 15kw portable generac ultra source. It ran lousy from brand new as well as had a slight leak when hot ( one or two drips on floor ). Generac is the WORST company I have ever dealt with. With a few hours on it Generac gave me where to bring it to. They also said a few jobs is acceptable. Keep in mind generator weighs 500 pounds and is no pleasant to transfer. I arrived and found their repair center to be somebody's house and got no answer. Called Generac and they sent me somewhere 55 minutes away. They looked at it and said I was using too high a grade gas and drop to 87 because it was running too rich. Made sense to me. Lost power for 10 days a year later. Ran like crap and brought it back. This time they said I'm not using enough of the power of the generator and the extra gas is burning off causing the pops. Made sense I guess. Hurricane Sandy came and was out for four days. Loaded it up, still ran lousy.

Now it's off warranty with under 100 hours. Paid my local non-generac shop to check it. Very quickly they found the bolts that attach the carb to the manifold were drilled off kilter. This cause the carb to not sit flat and was sucking air causing the popping and lean conditions. $50 for a new manifold plus labor. Thanks generac.

Good luck dealing with Generac but maybe check that first.

I bought a Honda a few days ago. I need it to run when I need it. The popping in mine got worse with time.

 

[General Lee]

Interesting that a couple of you guys are hearing the same. Mine is propane and is set to propane. I physically saw the tech make the switch under the air cleaner. Plus it was originally set to NG and didn't start right away before he realized to switch it over.

When we tested it after install it ran absolutely fine at full throttle and it hasn't run full throttle since. There hasn't been any power outages, so the automatic weekly test run is all it has done. My neighbor has the exact same set up and I don't notice the slight miss/pop on his. I wonder if something is slightly out of adjustment. I will have to check what the proper gas flow is per the manual.

I'm not comfortable enough to throw into manual mode. When the electrician simulated a power outage he didn't do the steps what the manual calls for and I'm worried I'll screw something up doing it myself. I have the 100 amp automatic transfer switch with all house breakers except for 3.

 

[hr3]

When you put the switch in manual your only running the engine not transfering load to the house.. Try it....

As far as doing the transfer test you should do it at least once a year...

 

[Pettrix]

I have the 15kw portable generac ultra source. It ran lousy from brand new as well as had a slight leak when hot ( one or two drips on floor ). Generac is the WORST company I have ever dealt with.

I've heard that Generac has had some issues. From my research I came to the conclusion that diesel generators are the only way to go if you want reliability. I will give it to Generac that they have some pretty good sales and marketing going on.

 

[daugen]

I believe the standard setup is for the unit to run at 2400 rpm instead of 3600 rpm at test. I have had my 20kw for almost three years, gone through multiple major outages, and the unit has run flawlessly. I have not heard any misfires during the test, but haven't been very close to it to hear it well either. The unit burns zero oil, the air filter is never dirty, and I change the oil with Mobil 1 and a new oil filter every Spring. The motor compartment still looks new, and the readout, after an initial low battery issue, has read "ready to run" ever since. I agree with annual transfer switch testing; that's a big solenoid in there and it makes a pretty good clank when it moves. And you want to make sure it moves...
I really don't think you can hurt the unit; the interface is pretty smart. Just rocker the switch off auto and start it on "manual" if you wish. I do that before changing the oil every year. And btw, Wix makes a fine replacement oil filter...

I run on propane, two large bottles, and after three days of running, the fuel meter only showed a drop from 75 (80 is full) to 60, so the thing is pretty efficient for our purposes. We have an all electric house and when the heat pump kicks on, we can hear the gen groan and the lights flicker once in a while. I've now learned to turn the hot water heater off during long outages, and that has helped, as we have three fridge/freezers.
Engine starts at 9 seconds and the lights come on at 16 seconds, every single time. And so far, no odd noises. Your installer should be able to go through the test procedure with you in about two minutes. If he isn't sure, you need a different guy. And i would definitely pop off the air cleaner and look down in there to make sure the fuel switch is in the right position. Seems every Tom, Dick and Harry is now a "backup home generator" installer, after our last storm. And most electricians don't understand the propane/LNG regulator issues, so it becomes a pointing match between the installer and the gas people.

 

[General Lee]

I believe the standard setup is for the unit to run at 2400 rpm instead of 3600 rpm at test. I have had my 20kw for almost three years, gone through multiple major outages, and the unit has run flawlessly. I have not heard any misfires during the test, but haven't been very close to it to hear it well either. The unit burns zero oil, the air filter is never dirty, and I change the oil with Mobil 1 and a new oil filter every Spring. The motor compartment still looks new, and the readout, after an initial low battery issue, has read "ready to run" ever since. I agree with annual transfer switch testing; that's a big solenoid in there and it makes a pretty good clank when it moves. And you want to make sure it moves...
I really don't think you can hurt the unit; the interface is pretty smart. Just rocker the switch off auto and start it on "manual" if you wish. I do that before changing the oil every year. And btw, Wix makes a fine replacement oil filter...

I run on propane, two large bottles, and after three days of running, the fuel meter only showed a drop from 75 (80 is full) to 60, so the thing is pretty efficient for our purposes. We have an all electric house and when the heat pump kicks on, we can hear the gen groan and the lights flicker once in a while. I've now learned to turn the hot water heater off during long outages, and that has helped, as we have three fridge/freezers.
Engine starts at 9 seconds and the lights come on at 16 seconds, every single time. And so far, no odd noises. Your installer should be able to go through the test procedure with you in about two minutes. If he isn't sure, you need a different guy. And i would definitely pop off the air cleaner and look down in there to make sure the fuel switch is in the right position. Seems every Tom, Dick and Harry is now a "backup home generator" installer, after our last storm. And most electricians don't understand the propane/LNG regulator issues, so it becomes a pointing match between the installer and the gas people.

Good Info daugen. I agree with your last few sentences. My installer did go over the test procedure in literally 2 minutes, thats why I can't really remember exactly what he did. I do know for sure he DID NOT use the manual lever rod in the transfer switch box for the solenoid. I believe he just hit the new generator breaker in the panel and it came on automatically. The manual calls for about 5 or 6 steps and he didn't all those steps.

So at least to run at 3600 rpm I can just switch the rocker on the genny to "manual" and let it run? And then just switch back to "Auto" when finished?

 

[daugen]

So at least to run at 3600 rpm I can just switch the rocker on the genny to "manual" and let it run? And then just switch back to "Auto" when finished?

yes, manual goes to full speed. You can tell, if only because it makes a lot more noise.
I put my gen in a flower bed, and toasted three feet of plant life downwind; that sucker puts out an enormous amount of hot air once it gets going.

there are different setups; if you have a gen breaker in your main panel, and not on the remote panel outside, then maybe that's all you need. My sister had the same unit put in two days before the storm, thankfully, and her setup was
different than mine when I walked her husband through starting the unit. Some of these units have extra circuitry for running multiple heat pumps, mine does not, only have one. Personally I'd call the installer back and ask him to run through the procedure again, while you take notes. But what you really want to accomplish is to turn off street power, to mimic an outage, and make sure the gen kicks on as it should. Then turn the street power back on, and the gen should run for a little while longer, on cool down mode, and then turn off. It may be hard to trust the electronics but if installed properly, they really do work and make sure you aren't backfeeding juice when you shouldn't.

 

[Toyboy]

The occasional pop when it doing it's weekly run is less concerning than when it goes to start it really don't wind up very fast. When we had the 8kw at our former home it would really wind up to start. This one has always seemed slower or have a less rpm starter. I even have the largest cranking amp battery that will fit in the compartment.

 

[BuzzardA91]

Don't overlook the manifold problem I posted. I believe my engine is same as the guardian series. The $50 manifold made a huge difference. Two generac dealers said some popping is normal. Don't buy it. It doesn't pop at all now. It definitely got worse over time. If your getting some popping its gonna get worse. Either the people I went to are incompetent or generac doesn't want to pay the repair for poor manufacturing. It will eventually suck more air and run so lean the muffler will glow and start causing premature oil breakdown and damage.

I'm sure I don't have the only poorly drilled manifold. I'm sure thousand went out that way until they eventually caught it.

My engine says manufactured in 2008

 

[daugen]

BuzzardA91, is there any way short of disassembling the entire carb manifold to verify if the manifold is an issue?
Generac is known for high quality, and I'm surprised this got past them. Their engines are a primo upgrade even for Z turns, and of course, their tech migrated to Vanguard, who (B&S) now owns them.

I spent a lot of time finding the max size Napa battery, their 72 month one, to fit in that small space. And so far, it's started just fine in the winter.
I'm wondering if the popping at test speed is because the engine is a little unhappy at that speed, perhaps the carb is set up/jetted for the normal 3600 rpm steady state use.
I'm definitely going to go out at next test time and listen to mine now, you've got me concerned.

 

[BuzzardA91]

Not sure on yours but they gave me a ton of excuses on the popping that all made sense at the time. Although I am not a mechanic by any means. Valves were adjusted, carb etc to no avail. Just kept getting worse. A visual inspection won't show I don't think. We took the carb off and you could see with the eye all four mounting bolts were all off from 90 degrees in the same direction. Manufacturing must have been set up wrong or something. For my particular problem it got so bad over time the muffler would be orange after an hour. If I pulled the choke out about 20% the popping got less but then the engine ran rough (as expected). It's not like the carb is off a bunch, it doesn't sit flat so it sucks air even if torqued down properly. It looks right with a visual inspection but off just enough to leak air.

I guess the short answer for my problem would be, minus removing the carb, it would be impossible to see. Once off you can visually inspect the bolts and see there is a problem.

Hope that helps.

At night the problem really stands out because you can see a blue flame from the exhaust every time it pops.

 

[BuzzardA91]

I don't mean to bash generac products. I just had a bad one that ended up being an easy fix. I know a ton of people who have them an very happy. Since this post the elderly lady had a 20kw generac guardian installed after last years October storm when we lost power for ten days. Been working fine I guess since when tested. Hurricane Sandy it ran for four days and I could hear it popping, but not as bad as mine. Just found out it needed to be fixed because some wires melted and the inside of the enclosure looks like it had a small fire. Wouldn't surprise me if its the same manifold problem. Hers ran longer then mine and the heat from mine would have definitely caught fire in an enclosure if ran for several hours.

 

[BuzzardA91]

After all the excuses and after the fix I thought about it logically. I don't have ANY other engines that run with a regular popping. Not sure why I believed the first few excuses they gave me. Popping is NOT normal for an engine running properly. Sometimes the fuel is the problem, but its always a problem with something. Just not normal.

 

[trumpeter]

You seem to have about the same load as I will. You say two large bottles, what size are they? If your gen ha sthe briggs built engine, the popping may be that it is running a little bit rich.

I believe the standard setup is for the unit to run at 2400 rpm instead of 3600 rpm at test. I have had my 20kw for almost three years, gone through multiple major outages, and the unit has run flawlessly. I have not heard any misfires during the test, but haven't been very close to it to hear it well either. The unit burns zero oil, the air filter is never dirty, and I change the oil with Mobil 1 and a new oil filter every Spring. The motor compartment still looks new, and the readout, after an initial low battery issue, has read "ready to run" ever since. I agree with annual transfer switch testing; that's a big solenoid in there and it makes a pretty good clank when it moves. And you want to make sure it moves...
I really don't think you can hurt the unit; the interface is pretty smart. Just rocker the switch off auto and start it on "manual" if you wish. I do that before changing the oil every year. And btw, Wix makes a fine replacement oil filter...

I run on propane, two large bottles, and after three days of running, the fuel meter only showed a drop from 75 (80 is full) to 60, so the thing is pretty efficient for our purposes. We have an all electric house and when the heat pump kicks on, we can hear the gen groan and the lights flicker once in a while. I've now learned to turn the hot water heater off during long outages, and that has helped, as we have three fridge/freezers.
Engine starts at 9 seconds and the lights come on at 16 seconds, every single time. And so far, no odd noises. Your installer should be able to go through the test procedure with you in about two minutes. If he isn't sure, you need a different guy. And i would definitely pop off the air cleaner and look down in there to make sure the fuel switch is in the right position. Seems every Tom, Dick and Harry is now a "backup home generator" installer, after our last storm. And most electricians don't understand the propane/LNG regulator issues, so it becomes a pointing match between the installer and the gas people.

 

[V1Rotate]

One way to check for any kind of vacuum leak or intake manifold leak is to get a can of carburetor cleaner and carefully spray it around the top of the engine and the intake manifold while the engine is running. Do not spray it into the air filter and use it sparingly so as not to create a fire hazard. If you have an air leak, you will hear a change in the sound of the engine. I have never done this on a generator engine but this technique works great on cars.