Onan gas 4000kw generator

[Luke D]

Originally Posted by saddlesore

Misaligned sail flap/switch?

Wow, thanks, never checked that. Not even an idea how or where to check. Still waiting on Cummins/ Onan here in Tampa.

[The_Breeze]

Originally Posted by Luke D

Everyone on this forum is awesome. Thanks so much for being so helpful. As a former classic car mechanic I hear you about jets. Very true. I even thought about buying a new carb. Quite the dilemma. Amazon $69.00, Onan $326.00. same carb??? Can't be but sure look identical

Order a rebuild kit if you have the tools to pull the carb. Locate the jets and pull them. Take a peek. If clogged, soak them overnight or try some brake cleaner. Reassemble, prime the gen, hit the rocker switch and say a prayer. If it fires up, look skyward and say thank you - to him, not me

[flrockytop]

Originally Posted by The_Breeze

Order a rebuild kit if you have the tools to pull the carb. Locate the jets and pull them. Take a peek. If clogged, soak them overnight or try some brake cleaner. Reassemble, prime the gen, hit the rocker switch and say a prayer. If it fires up, look skyward and say thank you - to him, not me

When I had cab problem on my last rv I I got exact cab on line for $14.. 5 min swap and on the road again. In spare time I tried to repair old one for spare. Replace all jets that were replaceable. Soaked in carb cleaner you name it. I did it. It worked better but still not good.



The one that I had that would start and run for about a min then stop turned out to be the fuel pump.

[workhorsed]

Originally Posted by Luke D

Can't go anywhere do to Covid , so every couple weeks I go to our storage lot to check on our RV. Of course run the engine and generator. Fuel tank was even filled up couldn't resist $1.57 a gallon, plus exercised our Thor ACE 30.1.
Problem gen a few times started hard but started and ran fine. Well last week it wouldn't start. Went outside primed then tried. It fired died instantly . Several times. Check gas flow and there was good flow. Spark fine. I figured after checking oil level ( full ). Maybe carb plugged or dirty. Pull had checked at local carb shop , they said no dirt , clean and could not find issue. Now the real issue , re installed. Engine wouldn't even fire. Now noise like something loose in engine is present. Not rod but like something dragging or rubbing on flywheel. Gen has 353 hours on it an has been well maintained. Guess I'll have it pulled. Seems to be mechanical now. Any thoughts????
Thanks

Don't do any more cranking! Check starter bolts, check rocker arms. Just pull the spark plugs and check for compression; the bad cylinder will reveal itself. Re-installing the rocker arm is relatively simple with the correct tools. If you're not comfortable, pretty much any mechanic can do it in around an hour, if there is no collateral damage. Lots of info on youtube Good Luck, stay safe. W.

[The_Breeze]

Found this:

Consumption at 1/2 load 0.3 GPH
Consumption at 3/4 load 0.5 GPH
Consumption at full load 0.7 GPH

Here: Cummins Onan Quiet Gasoline Series RV QG 4000 RV Generator Set

[taylorbob1]

Originally Posted by The_Breeze

Found this:

Consumption at 1/2 load 0.3 GPH
Consumption at 3/4 load 0.5 GPH
Consumption at full load 0.7 GPH

Here: Cummins Onan Quiet Gasoline Series RV QG 4000 RV Generator Set

Just wondering, if anyone knows...
Would a “full load” be running the Air Conditioner?
That is, once it starts the compressor, it doesn’t need as many amps to keep it turning.

[Chance]

Originally Posted by taylorbob1

Just wondering, if anyone knows...
Would a “full load” be running the Air Conditioner?
That is, once it starts the compressor, it doesn’t need as many amps to keep it turning.

Depends on A/C size and model. Also depends on inside and outside temperatures.

Having clarified that first, no, a typical air conditioner shouldn’t even pull 1/2 load of a 4kW Onan.

If you were powering a Power Saver at night, and liked it pretty cold inside, it would likely pull under 1,000 Watts, so about 1/4 load or less.

My 4,000 Onan could just power old inefficient A/C and microwave at same time, so roughly 1/2 load for my inefficient A/C in middle of hot day when it needed more power.

[knucklehead]

Originally Posted by The_Breeze

I thought I remembered reading somewhere that the 4kw gas generator will consume .6g either in a 1/2hr or hr. Can't remember. I believe the post was by ducksface. I can't find that post to save my life.

YES: it is .6 gallons per HOUR...Bob Trice

[Luke D]

Originally Posted by workhorsed

Don't do any more cranking! Check starter bolts, check rocker arms. Just pull the spark plugs and check for compression; the bad cylinder will reveal itself. Re-installing the rocker arm is relatively simple with the correct tools. If you're not comfortable, pretty much any mechanic can do it in around an hour, if there is no collateral damage. Lots of info on youtube Good Luck, stay safe. W.

Thanks , never pulled valve cover. I did pull plug compression wasn’t right. That's when I sent to shop. It's under warranty so let them fix?

[Beau388]

Originally Posted by taylorbob1

Just wondering, if anyone knows...
Would a “full load” be running the Air Conditioner?
That is, once it starts the compressor, it doesn’t need as many amps to keep it turning.

Running amp draw depends on the A/C''s size and the outside temperature. A 15,000 btu non-power saver will draw 18 amps in the 110 degree ambient shade and a 9,000 btu power saver will draw 9.2 amps at 80 degrees. Starting amps depend on the A/C manufacture and the size of the starting capacitor (20 to 40 amps for 1 second).

[Mo_Mike]

Originally Posted by Luke D

Everyone on this forum is awesome. Thanks so much for being so helpful. As a former classic car mechanic I hear you about jets. Very true. I even thought about buying a new carb. Quite the dilemma. Amazon $69.00, Onan $326.00. same carb??? Can't be but sure look identical

That is unless you have Cummins install a carb. Over 800.00. But, wasn't sure it was carb and the generator was under warranty (except for gas issues). I was running ours about once a month, but you can bet I run ours every two weeks now. I would definitely get the Amazon one if I need another one ( Cummins says they are prone to need replacement)