Momentum 21G generator won't start

[rvoelker]

New 21G and am going through my basic system checks before maiden voyage: Generator won't start.
X - Can't reach Grand Design Customer service
X - Have been unable to reach dealer service department
√ - first post to this forum got me a couple of great answers in a short time!

Yeah, I know I should have been more patient but it was late in the day when we bought it and we wanted to get on the road(dealer said it had been prep'd earlier for a deal that fell through) so I didn't take a full pre-delivery walk-through).

Setup
- Is an Onan QG 4000 generator
- Single fuel cell is above 1/4 full (is 1/2 full just to be sure) BTW - why do they require 1/4 tank? I don't want to drag around 50Lbs of gas after my gen conks out!
- checked the generator oil level
- followed instructions in owners manual
- done most of my testing from the generator panel
- pressed the Prime button multiple times, up to 30-40 seconds each try over multiple days/attempts
- checked the 12vDC panel for blown fuses, in particular the Fuel Station fuse(which I figured might service the Generator fuel pump, and is not blown, and Fuel Station pump works)

Symptoms
- when pressing start switch on the generator to the prime position I get a faint click in about 1-2 seconds after pressing and holding. Red light comes on solid.
- when pressing start button to the start position, engine cranks normally
- there is no fuel coming out of the carb supply side fuel line when the prime button is pressed, nor when the engine is cranking
- I can hear nor feel any action out of the fuel pump when the primer button is held down - just the click
...and just for fun - manually supplying fuel to the carb inlet allows the generator to fire.

Questions
Is there a secret fuel shut-off valve not mentioned in the owners manual(or that I could not find)?
Can a person hear or feel the fuel pump when it is in operation?
On a brand new, never run(presumably) install is it reasonable to expect a greater than several minute prime the first time?

Considering my luck reaching anyone at GD or the Dealer, and how long a warranty fix is likely to take, and that summer is slipping away I'm considering just replacing the fuel pump myself if I can get any corroboration on my symptoms from the forum.

Thanks again -

[ncitro]

rvoelker Unfortunately I don't have one so I'm not a huge help, but I would be shocked if it did not have a fuel shutoff somewhere, I'd expect it either right at the generator or right at the tank, probably the latter. I'd trace the line back looking for a shut off valve.

[Country Campers]

Another thought with this is a while back there was a post on the fuel tank gauge not working properly. Your gauge may be showing a fuel level but may be wring.

Brian

[flyfshrockies]

rvoelker We don't have an onboard generator so FWIW. All of the above suggestions are good, the fuel gauge could be inaccurate for sure and a shut off could be well hidden. A couple of other thoughts, check the fuel filter, it could be clogged from stuff in the tank and line from installation or the filter could be mounted in reverse. I did that one time and it caused issues. Regardless of weight, I would start with a full tank of fuel and start from that point, making sure the tank vent works as well though that would probably show a run then start symptom. Check all wiring connections while you are at it. Good luck.

Dave

[rvoelker]

I can with some degree of confidence be sure that in this case the gauge(s) are indicating correctly. This was a bone dry delivery that I added fuel in three passes;
- 1st fill, 5 gallons - wouldn't start. (then learned it had to be at least 1/4 full)
- 2nd fill, 5 gallons - to get above 1/4 full, wouldn't start.
- 3rd fill, 8 gallons - to insure well above 1/4, wouldn't start. (that put me right about where the fuel gauges read - both the inside steam gauge and the Fuel Station LED indicator)

The Onan fuel pump is described as a 'micro quiet' pump. Has anyone ever listened to it while priming? Can you hear anything/it spinning? ..all I hear is a solenoid click. I've heard a few fuel pumps in my day but never one that doesn't make any noise or vibrate at least a little.

My thoughts at this point are to just order the $25.00 pump so I have it on hand for the weekend, get in there and trace the fuel lines for a shut-off, review the wiring for proper voltages, and drop in the new pump if necessary.

Thoughts?

[ncitro]

I can with some degree of confidence be sure that in this case the gauge(s) are indicating correctly. This was a bone dry delivery that I added fuel in three passes;
- 1st fill, 5 gallons - wouldn't start. (then learned it had to be at least 1/4 full)
- 2nd fill, 5 gallons - to get above 1/4 full, wouldn't start.
- 3rd fill, 8 gallons - to insure well above 1/4, wouldn't start. (that put me right about where the fuel gauges read - both the inside steam gauge and the Fuel Station LED indicator)

The Onan fuel pump is described as a 'micro quiet' pump. Has anyone ever listened to it while priming? Can you hear anything/it spinning? ..all I hear is a solenoid click. I've heard a few fuel pumps in my day but never one that doesn't make any noise or vibrate at least a little.

My thoughts at this point are to just order the $25.00 pump so I have it on hand for the weekend, get in there and trace the fuel lines for a shut-off, review the wiring for proper voltages, and drop in the new pump if necessary.

Thoughts?

I'd be genuinely surprised if the fuel pump was bad brand new. We joke a bit about the quality inspection off the line (how much can they check when the walls are all up) but I'd have to think someone at some point fired the thing up before you got it, even if it was only Onan. I'd really look for the fuel shut off to start.

[Jlawles2]

rvoelker If there is a convenient place to disconnect the fuel line at the generator start there and see if you can get fuel. That will confirm or deny the fuel supply issue. From there if all is good, try the carb next (if not already there) you may need to tap the bowl (it really still has a carb?? I thought everything was going FI now). to see if the needle valve is stuck. You can also try a shot of brake cleaner in the intake to see if it will at least try to start. Don't forget to check the choke to see that it's functioning (this will cause major headaches).

If all checks out, pull a plug, carefully ground it and watch for the sparkies while trying to crank. Look for any chafed wires leading to the coil packs in case the kill line is shorted out.

Don't forget to check the oil level and it's sensor. Some will not fire off if there is no oil.

[rvoelker]

FIXED!

Work was a little light at the office today so I decided to just handle it. It's 92 degrees out and am sitting in the air conditioned cabin (another ops check complete!) listening the generator doing it's thing.

I've been around engines for a lot of years and was on the fence about attempting a fix or going through the brain damage of executing on my Warranty. Having never heard this type of fuel pump running I was just not sure, which is why I reached out to the forum.

ncitro - I would have been surprised if a brand new, factory checked, pump was bad, too - so I yanked it and did a bench test.
- for those who have never heard one, the 'MicroQuiet Fuel Pump" makes a light tapping noise when running and not moving fuel, just like any old electric fuel pump. Definitely obvious to the ear when running.
√ Thats what this one did on the bench

Upon reassembly -
- press prime button: tap-a-tap-a-tap-a and then a light buzz/hum when it had fuel moving through it.
- press start button - crank-a-crank-a-vroom!

Final diagnosis was that the minus/grounding lead from the fuel pump was mangled on the grounding bolt/lug and not making any connection (the one that goes through generator chassis to the black battery cable). Re-working that connection and lug solved the problem.
- I guess I am now in the club who can joke about Grand Design quality inspection

** For future reference - in the prime position the switch light flutters to indicate pump action(if you can't hear it). It is a solid red light when pump is not operating/spinning (fault).

Thanks to the forum - all your troubleshooting suggestions and 'you might wanna check' ideas were spot on.

No thanks to Grand Design(never responded) or my dealer(never called back), nor to Cummins tech support who only warned, "take it to your dealer or you'll void your warranty".

[ncitro]

rvoelker Glad you got it! Support can be tricky, in particular GD is just coming out of the national rally which ended Saturday, so they could be dealing with getting people back into position. Thats no excuse for not getting a call back, just letting you know.

[acoleman43]

rvoelker I'm a little late for this one

The fuel pump is quiet. Glad you got it all figured out.

[ThePowells]

rvoelker Welcome to the forum and the Family!.

When you get a chance, check out the forum welcome letter which will hopefully make your forum usage a little easier.

https://gdrvowners.com/forum/main-fo...to-new-members

[tgodrich]

My toy hauler I used to have had an on board fuel station. Within this, it also supplied gas to the generator. There was a pipe from the top of the tank into the tank that was the draw for the generator. This pipe went in only about 3/4 way, so that the generator would not draw all the gas out of the fuel tank. It would quit drawing at about 1/4 tank, as described above, by design. I think this may have been a boil over design from motorhomes that have a generator also supplied by the fuel tank. This would assure that the generator would not run the fuel tank dry such that you could not start the motorhome.

Anyway, that was the way my toy hauler fuel draw worked for the generator from the factory. I moved the generator line to the main tank draw with a Y so that I could run the fuel station less than 1/4 full and still supply the generator. If I needed dirt bike gas, I made sure I pulled it into a can prior to running the tank out with the generator. Hint... Put a secondary fuel filter inline with the generator too, if your going to run the tank dry. There can be sediment at the bottom of the tank.

Hope this helps.

[rvoelker]

Agreed about the generator fuel draw depth being a hold-over. Good idea to do a Y off of the main tank draw.

Most of the bikes I carry are 2-strokes and am not likely going to mix at the race track so reserving a quarter of regular in the fuel cell is not necessary. Like they say in the aviation industry, "It takes more gas to fly more gas". I'd rather not drag around gas that I can't really use.

[flyfshrockies]

rvoelker Usable fuel is always nice. Our aviation saying was if you you are leaving fuel behind you need more airplane, or in this case more truck? Another good one was that, the runway behind, the sky above, and the fuel in the ground were of no use to you.

Dave