Onan 4KW - Fix it or Replace it ??

[Wbago]

I have a none-working Onan 4000 Microquiet fitted in my RV, that hasnt worked since i had it ... turned over a couple of times, it starts then dies, and thats all i know ...

My thoughts are that a cheap genny might be easier for me, but im wondering what power i will need, as 4kw seems a lot for camping lol ...

Question is really, what is the smallest genny thats worth me getting, to power the aircon, and assorted appliances, nothing bigger than a kettle ... a suitcase genny thats about 850w is around £100, and even a smallish repair on the Onan will be more than that
must also be 240v, straight hook to shoreline (UK)

thoughts??

[Rickf1985]

It may just need some simple cleaning, I would spend a little time with what you have first. You are going to need close to 4k because of the Air conditioner. When it first starts are you holding the switch on start for a few seconds until the light on the dash stays on? Or if you are at the generator just hold the switch for a little bit to flash the field to make sure it is putting out power. This is Daves favorite area of expertise so I am sure he will be here soon.

[DaveVA78Chieftain]

4K genny = 33 amp output.
You said air conditioner so you just said you need a 4K genny.
AC running amps is ~13.  Close to 20 amps to start compressor which is why it is wired to a 20CB.
The AC was why the RV standard went from 15 to 30 amps in the 70's.
The other 10 amps is used to run the rest of the rig.
It is possible to pop the 30 amp service breaker if the compressor starts up while the microwave is running.

Post the full model and serial number of your genny and maybe we can figure out what is wrong with it.

Dave

[M & J]

Or we'll try like the dickens.

[Wbago]

Its an Onan 4000 KY ...

s/n is 4KYFA261008 ... or that 8 might be a B

Im getting no fuel to it now, so might be fuel pump issue unless theres a cutoff valve somewhere ... plenty fuel in the tank ...

[DaveVA78Chieftain]

4KYFA26100B is actually the model number, not the S/N. Page 1-2 of the service manual tells you how to decode them for model, features, and DOB.

Troubleshooting is based on Spec # so I will assume the 8 is actually a B for Spec B

Operators, Service and Installation manuals are in Members Free manuals area.

Will check into it later tonight - have to take wife to dinner.

Dave

[tiinytina]

question does your's have it's own fuel pump? or not? I'd pull the fuel line from gas tank run tube into a can of gas, crank it.. may be just the fuel pump on the genny itself not pulling.... in same line after you pull the line off the main tank is there fuel draining from it?  is there a filter? have you changed it?  sorry if been there did that already

[DaveVA78Chieftain]

Getting gas to the unit is first step.  Tina's comment is the right approach.  May simply be that one of the rubber hose connections between tank and Onan is cracked allowing pump to just suck air.

Dave

[DaveVA78Chieftain]

The original Onan in your rig was replaced/upgraded to the KY Microlite which is a 3600 RPM unit.  Be sure to download the service manual so you can see where all the parts are.  It has a troubleshooting section.  Just remember you have a Spec B unit.

Dave