Log In | Register
Skip to main content
Topic: Generator Won’t Start (Read 613 times) previous topic - next topic
0 Members and 4 Guests are viewing this topic.
Generator Won’t Start
I posted a thread on this a few months ago...thought it best to start a new one for clarity.

2014 27’ Midbath.  Onan RV QG 4000, 4KYFA26100P

Background: I went to my shop where I store my RV so that I could exercise the generator.  I have 1/2 tank of gas, strong charge to the battery.  I primed the generator & attempted to start it.  It cranked well, but never fired.  I went through the cycle several times.  Tried again today with troubleshooting in mind.

Again, 1/2 tank of gas in the RV.  Fully charged battery.  Verified about 13V to the starter solenoid on the generator.  Confirmed good oil level.  Primed, attempted to start, no luck.  Cranks but never fires.  No error codes.

Checked for fuel in the fuel bowl.  Yes.
Checked for fuel delivery to the carburetor.  Yes.
Removed the spark plug.  It was actually wet (gasoline),
Grounded the spark plug and ensured a good spark while cranking.  The spark appear strong, white/blue (I have a video of it if anybody wants to see).  I’ll attach a picture of the spark plug below.  Note that the gas had mostly dried before taking the picture.

All things considered, it seems to me there’s inadequate air getting into the cylinder.  Gas seems to be making its way into the combustion chamber (based on the wet plug), the spark plug is firing, but the engine doesn’t start.  I ensured the linkage going into the carb is free, and I can actuate it manually, but I didn’t see any movement at all when attempting to start the engine.  I wonder if the choke is being held closed, starving the engine of air?

Any other ideas?
Still pretty new to RV lifestyle & Lazy Daze
2014 27’ MB
Two beautiful Weimaraners, Junie & Pearl (now our angel dogs)
Re: Generator Won’t Start
Reply #1 –
After a little more reflection, I’m now thinking that float may be stuck, or the needle & seat gummed up so there’s nothing to stop the flow of gasoline into the intake manifold—and as a result my generator is flooding.  So the gas on the plug isn’t due to a lack of combustion from air starvation—but just a simple matter of unregulated gas flooding it.
Still pretty new to RV lifestyle & Lazy Daze
2014 27’ MB
Two beautiful Weimaraners, Junie & Pearl (now our angel dogs)
Re: Generator Won’t Start
Reply #2 –
These carbs are notoriously problematic if not run frequently.  If you take it to a shop, the most common fix is to replace the whole thing b/c labor costs make rebuilds expensive.

If you suspect things are sticky inside, you can try cleaning it up.  As the NPR Car Guys used to say 'Go to the auto parts store and find something that says miracle on the bottle!"

I use seafoam, for no other reason than I usually have some around.  You can drain whatever is in the carb using a screw on the bottom of the bowl.  Then you can disconnect the fuel hose between the pump and the carb and use a syringe or something to inject the cleaner.  soak, drain, repeat if you want to, eventually try fuel again. 

Maybe it won't work, but that's what I would try on mine if I suspected a gummed up carb. 

Rich
 
2003 MB
Re: Generator Won’t Start
Reply #3 –
Thanks Rich.  I’ll give that a try.  I’ve heard that even disassembled, these are notoriously hard to clean once varnish has established itself.  But I’ll certainly try before spending $350 on a replacement. 

There’s a ton of off-shore knock off carburetors on Amazon & eBay.  Tempting to get a replacement for $45, but I don’t want to stray from the manufacturer on something as important as my generator only to find myself out of luck in the boondocks!

Once I get this resolved, I plan to install a shut-off valve in the fuel line next to the carb.  I want to shut off the gas & drain the float bowl after each trip & before storage. 

Jay
Still pretty new to RV lifestyle & Lazy Daze
2014 27’ MB
Two beautiful Weimaraners, Junie & Pearl (now our angel dogs)
Re: Generator Won’t Start
Reply #4 –
Jay, draining the carb before storage is not a bad idea, but it does not get you around the recommendation to run the gennie for at least one 2-hour run under load per month.  The issue is that you are avoiding moisture and corrosion in the generator portion, as well as re-lubricating the engine parts.

As to dealing with the carb now, and the possibility of varnish causing problems, Seafoam might be good, but my instinct would be to get a can of carburetor cleaner and empty the can via multiple spraying, several minutes apart.  That having been said, I am NOT an expert on engines, so this is just a wild-assed guess on my part.  Its basis is that if I am cleaning a carb, I want to use a material designed and intended for cleaning carbs.

Ken F in NM
'08 MB
Re: Generator Won’t Start
Reply #5 –
Is it throwing a code? See manual to see how to display them.
I would bet on the carb.
Don & Dorothy
Sold our LD in June of 2023

Our boring always non-PC travel blog
Traveling Dorothy
Re: Generator Won’t Start
Reply #6 –
Quote from: Don Malpas  - 
Is it throwing a code? See manual to see how to display them.
I would bet on the carb.
Don, I don’t believe so.  I get the “over crank” code (4 flashes), but not the “service needed” (3 flashes).  Without the 3 flashes, there’s no code to retrieve, correct?
Still pretty new to RV lifestyle & Lazy Daze
2014 27’ MB
Two beautiful Weimaraners, Junie & Pearl (now our angel dogs)
Re: Generator Won’t Start
Reply #7 –
Quote from: Kenneth Fears  - 
Jay, draining the carb before storage is not a bad idea, but it does not get you around the recommendation to run the gennie for at least one 2-hour run under load per month.  The issue is that you are avoiding moisture and corrosion in the generator portion, as well as re-lubricating the engine parts.

As to dealing with the carb now, and the possibility of varnish causing problems, Seafoam might be good, but my instinct would be to get a can of carburetor cleaner and empty the can via multiple spraying, several minutes apart.  That having been said, I am NOT an expert on engines, so this is just a wild-assed guess on my part.  Its basis is that if I am cleaning a carb, I want to use a material designed and intended for cleaning carbs.

Ken F in NM

Ken, understood.  I still intend to exercise it monthly.  And for now, I’m worried about what may be waiting for me after letting it sit so long once it failed to start.
Still pretty new to RV lifestyle & Lazy Daze
2014 27’ MB
Two beautiful Weimaraners, Junie & Pearl (now our angel dogs)
Re: Generator Won’t Start
Reply #8 –
Quote from: Kenneth Fears  - 
Jay, draining the carb before storage is not a bad idea, but it does not get you around the recommendation to run the gennie for at least one 2-hour run under load per month.  The issue is that you are avoiding moisture and corrosion in the generator portion, as well as re-lubricating the engine parts.

Thanks for mentioning the 2-hour run time, Ken!  For some reason I thought it was only 1-hour and that’s what I’ve been doing the last couple of months since I returned home with Nocona.  I just looked in the Lazy Daze manual and, sure enough, it states that Onan recommends at least two hours per month run time.
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264
Re: Generator Won’t Start
Reply #9 –
During Covid I did not run my generator every month as recommended.  Come December - we could not get our generator to start.  It would crank - but not start.  I got all the parts to service the generator from Cummins - minus the carburetor . Not in stock.  My honey took the carburetor out and cleaned it with carburetor cleaner, after checking spark plug, filter and oil.  Luckily, we got it working so we could go boon docking in the desert.  From the YouTube videos, this does not always work and have to replace the carburetor.  We used the videos to show us how to take the carburetor out. 
2017 RB 27'
 
Re: Generator Won’t Start
Reply #10 –
Hi Jay,

I went back and read your original post about the generator not starting. At that time, I thought you were going to go back to the storage place with a new sparkplug?

Based on my experiences with gas powered equipment, the sparkplug in your photo is beyond drying off or cleaning. Possibly the nastiest looking plug I have seen.. Replace it before you start digging into the carb or choke. You might get lucky and solve your problem for the cost of a new sparkplug!

You can also reach in and move the choke or throttle levers to make sure they are not stuck. I would also try some starting spray to see if it will fire up.

If you get lucky and get the generator running, let it warm up and then change the oil. I would think with the fuel system being badly flooded your oil has been contaminated with excess fuel.

Good luck, it must be pretty cold in your area. I hope you didn't deplete your house batteries.

Steve K
Steve K

2003 Mid-bath
Re: Generator Won’t Start
Reply #11 –
While on the subject of carbs does anybody know if the OEM version has been discontinued?   I have been looking for sometime and put my name on a waiting list but no success.  I bought one of those $60 knock-offs to try but would prefer the manufacturer's version.

Bob
2006 RK
Re: Generator Won’t Start
Reply #12 –
Quote from: Steve K.  - 
Hi Jay,

I went back and read your original post about the generator not starting. At that time, I thought you were going to go back to the storage place with a new sparkplug?

Based on my experiences with gas powered equipment, the sparkplug in your photo is beyond drying off or cleaning. Possibly the nastiest looking plug I have seen.. Replace it before you start digging into the carb or choke. You might get lucky and solve your problem for the cost of a new sparkplug!

You can also reach in and move the choke or throttle levers to make sure they are not stuck. I would also try some starting spray to see if it will fire up.

If you get lucky and get the generator running, let it warm up and then change the oil. I would think with the fuel system being badly flooded your oil has been contaminated with excess fuel.

Good luck, it must be pretty cold in your area. I hope you didn't deplete your house batteries.

Steve K


Steve, a new spark plug will be here on Monday.  I’ve also got an Onan carburetor on the way—pretty certain I’ll need it.  If I get lucky and don’t need the carburetor, it is returnable.  An oil change is definitely in the plan!  And yeah...it’s pretty cold here!  But I have a large garage condo (my shop) where I store my LD and tend to my car hobby.  It’s climate controlled so nice & comfy.  I keep a fresh charge on the batteries.  Curious though...I had the impression the generator is started with the chassis battery—not the house batteries.  Does it actually draw from the house batteries?

Bob, for the QG 4000 in my coach (4KYFA26199P) RVupgrades.com lists part code 48-2116 as the replacement carb.  It is Onan OEM. 

MFG P/N: A042P619
MFG: Cummins Onan

Jay
Still pretty new to RV lifestyle & Lazy Daze
2014 27’ MB
Two beautiful Weimaraners, Junie & Pearl (now our angel dogs)
Re: Generator Won’t Start
Reply #13 –
"Steve,  Curious though...I had the impression the generator is started with the chassis battery—not the house batteries.  Does it actually draw from the house batteries?"
Jay

Hi Jay,
Glad to learn you have climate controlled area to work in. I am so jealous! Living in NE Ohio, your weather is heading here. Sure ain't pretty other than for ice fishermen!😀

Back to your question about which battery is used to start the generator, unless something has changed over the years, the generator uses the house batteries to start. That is how it works on my 2003; I would refer you to your Lazy Daze Owner's Manual for your 2014. I also note that another Steve mentioned checking the house batteries (in the original discussion about your genset starting problem) to see if they were strong enough to give the sparkplug a strong spark. I assume you have had the rig connected to shore power and your house batteries are fully charged? If not, put a charge into those batteries to rule out battery issues.

Good luck,
Steve K



Steve K

2003 Mid-bath
Re: Generator Won’t Start
Reply #14 –
Hi Steve...house batteries makes sense.  Reduces chances of getting stranded somewhere!

Sorry for sending the cold weather your way.  Looks like it’s going to settle in for about another week.  After the very easy winter we’ve had so far I guess we probably had this coming!   
Still pretty new to RV lifestyle & Lazy Daze
2014 27’ MB
Two beautiful Weimaraners, Junie & Pearl (now our angel dogs)
Re: Generator Won’t Start
Reply #15 –
Hi Jay; My '99 uses the house batteries to start the generator. In a pinch you can start the vehicle engine. The alternator can put a lot of amps into the house batteries (especially if you don't have a diode isolator) to help start the generator. Being stranded with a running engine is better than having a running generator that won't 'move on down the road.'  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Generator Won’t Start
Reply #16 –

Jay,

I'll just add my $.02 to the discussion, since I recently dealt with exactly the same issue.  I, too, have a 2014 mid-bath with the same Onan generator.

The coach had been parked in the driveway at home since March 25 (after returning from Morro Bay/San Simeon a few days after the first COVID-19 lockdown).  When I tried to start the generator in August, it would crank, but refuse to turn over.  Unlike you, I was getting a code 36 on some of the attempts (from a motor boat forum, "engine has stopped with command from controller, so either you have a fuel supply problem, combustion air supply problem or as JFM suggested the ambient air temperature has de-rated the engine output below the load on the generator and the engine has stalled").

I responded to this by pulling out the spark plug.  I saw that it was wet, and perhaps a bit fouled, so I decided to replace it, and while I was at it I decided to replace the air filter and change the oil, since it had been almost six years since taking delivery from LD. 

After all of this, I managed to get it started after about six or seven attempts, with one of the attempts throwing the same code.  I let it run for about two hours, then shut it down.  I ran it repeatedly, but it would always take anywhere from three to eight or nine attempts.  I found that starting the coach engine beforehand seemed to help, as this increases the house battery voltage.  The same hard-starting behavior persisted for months, through a couple of trips, so I figured that it had to be a gummed-up carburetor.

After returning home from a three-month trip just before Christmas, I resolved to do something about it, and I found this video online: https://www.youtube.com/watch?v=wX6Pbh7HEMU .  There are quite a few similar videos detailing the "can and hose" method, using Seafoam ( Amazon.com: Sea Foam SF-16 Motor Treatment - 16 oz.: Automotive ). 

It's pretty simple: I used a small gas can, put about a gallon of gas in it, and mixed in about 4 (or 6) ounces of Seafoam.  Then I pulled the fuel line off the generator - the fuel line is held in place with a crimp-style hose clamp, which I just cut off with a pair of end-cutting pliers - and quickly plugged it with a stubby #2 phillips screwdriver, which fit into the line snugly, no drips.  Finally, I slid on the temporary fuel line, cinched it up with a small screw-type hose clamp, dropped the other end into the gas can, and fired up the generator.  I let the generator run for about half an hour, then shut it down, then waited for about an hour and started it up again.  It still took about three attempts, but then I let it run for another hour, then shut it down.  Every time since, it has turned over on the first attempt - definitely an improvement.

Seems good to go, at least for the time being.  From now on, I will be disciplined about running the generator under load at least two hours per month.

Question for gurus: how difficult is it to replace the carburetor on one of these units?  Do you actually have to take the entire generator out in order to get at it?  I had a difficult enough time just removing and replacing the spark plug!

Regards,

Tim

As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
2014 Mid-Bath
2014 Honda CRV toad
Re: Generator Won’t Start
Reply #17 –
Hi Tim,

I’m glad you got yours running!  Way to go!

I bought this LD about three years ago from the original owner, a friend of mine.  The generator was always tough to start.  But as of about 15 minutes ago, I think I may have the easiest starting, best running generator in the LD fleet! 

I bought a new Onan carburetor from RVUpgrades, and a new NGK spark plug & Onan air filter off Amazon.  I went down to my shop today to install it all.  The carburetor took me about an hour and a half—maybe two hours.  It’s very straight forward, but re-installing the bolts is a blind operation and a pretty awkward, crowded reach.  More on that in a minute. 

Once I had the new carburetor, air cleaner & spark plug installed, I gave it about a 20 second prime and hit the starter.  It fired immediately and ran great.  I ran it for just a few minutes then shut it off to inspect for leaks.  All was good so I re-fired it.  Again, it jumped to life and ran smoother than I’ve ever heard it run since I bought it. 

A couple notes on the carburetor R&R.  First of all, this was all done with the generator installed in the coach.  No need to drop it.  I carefully covered the solenoid & all wiring in plastic, then laid down a couple shop towels to ensure I couldn’t arc anything across the wires.  I know I should have disconnected the house batteries—but felt safe enough proceeding without doing so.  I then disconnected the fuel line & the ground wire running from the carburetor to ground.  Then the air filter cover & element come out.  Inside the air cleaner housing is a pair of bolts with 10mm heads.  Use a 10mm socket on a 1/4” drive with about 6” of extension to back those out.  The carburetor then slides towards you with the linkage still attached.  It’s a simple matter of tilting the carburetor and slipping the choke & throttle linkage free (there’s also a spring in the mix...don’t forget to reattach it).  You’ll also then be able to easily unplug the “hot” wire between the carb & the harness.

Reinstalling it is just doing the same things in reverse order.  You’ll need to use gasket adhesive to secure the gaskets in place and let them set thoroughly or the gaskets will slide out of place during installation.  The most time-consuming part for me was getting the bolts back in!  I tried for too long just using my fingers and had no success.  Eventually I used a mirror and small shop light to see what I was doing, and used a short socket and extension to feed the bolts into the holes.  There’s a little bit of twisting and turning of the carb required while feeding the bolts through the air filter housing, carburetor and manifold.  Again, gasket adhesive kept the gaskets in place while doing so.

Be sure you have a new hose clamp on hand (you have to destroy the original one when removing the fuel line).

I’ll head back down in a day or two to run the generator for a couple hours under load.  I also plan to drain the gas from the float bowl when done. 

Jay
Still pretty new to RV lifestyle & Lazy Daze
2014 27’ MB
Two beautiful Weimaraners, Junie & Pearl (now our angel dogs)
Re: Generator Won’t Start
Reply #18 –
Jay,

Thanks for the excellent, detailed description of how you replaced your carburetor!  You must have surgeon's hands.

I'll be sure to refer back to it if (or when) I decide to do the same.

Regards,

Tim
2014 Mid-Bath
2014 Honda CRV toad
Re: Generator Won’t Start
Reply #19 –
I need to take a closer look at mine.  How do you drain the carburetor bowl, and is it a necessary step if running the generator on a monthly basis?
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264
Re: Generator Won’t Start
Reply #20 –
Quote from: HiLola  - 
I need to take a closer look at mine.  How do you drain the carburetor bowl, and is it a necessary step if running the generator on a monthly basis?
It shouldn’t be necessary if you run the generator regularly, but it’s easily done so I’d rather take the extra step to try & minimize varnish build-up.  At the bottom of the carburetor float bowl there’s a stainless steel screw that can be backed out to open the drain.  There’s an outlet/nipple underneath that a section of 1/4” fuel line can be fitted to, so you can collect the gas in a can vs. just allowing it to drain into the catch tray underneath the carb. 
Still pretty new to RV lifestyle & Lazy Daze
2014 27’ MB
Two beautiful Weimaraners, Junie & Pearl (now our angel dogs)