Onan generator replacement

Just to let you know it is possible to fix the Onan reasonably sometimes.

I wanted an onboard gen that can come on when we are away if it gets too hot for our animals and there is no power. (texas is brutal in the summer)..
I found a used 7kw unit, not working, for $200.. assuming that the rotor was broken..

doing some testing (thanks to smokstak.com forum), seems that the drive belt pulley (rubber between to metal parts) had finally fallen apart (this unit has 4,000 hours).

$45 including a new belt (why not?) and a few hours work and voila!.. perfectly good gen. still have to add trifuel and install it, but have tested powering the FW with no problems.

Why don't you just pull it out and get a Honda or Yamaha and store it in the spot where the Onan used to live. Cheaper and quieter.

go camp out in the forest and run what you brung. Parks are way too crowded anyway. Like living in an apartment compared to a house on an acre. Over 15 yrs and only in a park 3 times, had no choice BUT here in Az we have lots of space unlike the east & midwest.

The portable Hondas are only "whisper quiet" when running in the lower one-fourth of their power output bands. I've heard the 2000i fully rev'd up in campgrounds and it's way more irritating (due to it's sound spectrum at full RPM and their full RPM speed) than my built-in Onan 4K is listening from outside our RV.

The portable Honda inverter generators rev above 4000 RPMs when at their full power ... while the Onans run at 3600 RPM at all powers. Which is going to be louder-per-watt-produced at full power? My built-in Onan sounds about the same whether putting out 200 watts or 4000 watts, so .... if one wanted to quiet their Onan down further with glued in sound insulated and full isolation mounts .... it would be a formidable competitor in the watts-versus-sound-level RV world.

I'm pretty much convinced that the low-sound reputation that the Honda inverter generators enjoy comes from most folks using them the bulk of the time at way reduced power levels from maximum.

FWIW, I have a constant speed Honda portable generator for battery charging that not only runs at a constant 3600 RPM regardless of the power I'm drawing from it ... but while doing this it's sound level is only 1 dB louder than the lowest noise specified for the Honda 1000i and 2000i inverter generators. I use it in tenting sites when even our built-in Onan might be too loud for our green neighbors.

We are talking about a couple of different issues. Running a Honda 2000i next to anyone's model mounted in an RV is a huge difference, but I have yet to see someone with a large output (4000+) that is "whisper quiet" like the Honda 2000's. Run the Honda in a tent campground and people might look the other way. Run ANY 4000 in the same conditions and people will be asking when you are turning it off.

That said, if you look up an Onan QG 7000, it shows a noise rating of 70 db. Look at the HF equivalent model (8500) and it shows 76 db. That would be noticeable, but not huge. Also notice that the Onan is a fully encased design and runs you $5000. I very much trust an Onan genny, but I would have a VERY hard time justifying the $4500 price difference. Especially when folks like Consumer Reports list the HF genny as a top of its class purchase.

From where I sit, if you can mount the HF genny inside your RV, it most likely has a properly insulated generator compartment and noise will probably not be an issue. Adding a sound shield to bring it down to the same noise level as the encased Onan would probably not be very difficult either.

The one thing to sort out is the fuel supply. The HF genny has a gravity feed carb, so you might need to do something special about that. Considering the $4500 price difference compared to the Onan, that seems like a very small inconvenience.

Jose

N-Trouble wrote:
Not true... Put a Onan 5500 next to a Onan 4000 and the difference is night/day. 5500 is MUCH quieter.

Do you mean "put an Onan 5500 out in the open next to an Onan 4000 out in the open" and the difference is night/day?

Or do you mean "put an Onan 5500 as mounted in the typical RV next to an Onan 4000 as mounted in the typical RV" and the difference is night/day?

Today's versions of those two Onans are 4 dBs apart in sound at half-power. Probably not a night and day difference ... but the sound spec for both of them is really too loud. Either one should be installed in an RV properly for their quietest operation. How they're installed in any particular RV probably can make a night and day difference.

DaHose wrote:
Big genny's just plain old make noise folks.

Jose

Not true... Put a Onan 5500 next to a Onan 4000 and the difference is night/day. 5500 is MUCH quieter.

I know they are few and far between these days, but try to find a small electric motor rewind shop and see if they can rewind it for you. Also the rotor and stator both have coils and hopefully both aren't bad. Have the shop test and determine which it is. Also a good motor man/winder may be able to repair the fault without a full rewind if the problem can be located without damaging the coil turns around it. The $5000.00 quote is ridiculous. Look at used onans where RVs are parted out and the will be thousands less for the entire unit.
Good Luck with this. You can do it much more reasonably than for 5gs.

DaHose wrote:
That's a deal, glennts.

As to noise question on the HF genny. My Onan 4000 BFA is PLENTY loud when it is running. I can't imagine that the HF units would be a big difference, plus you can add a high rise exhaust (there's a name for that) with an additional silencer inline. Although, I put a spare muffler on the exhaust output of mine out of curiosity and with the exhaust note cut down, I could now hear all the mechanical clacking. Big genny's just plain old make noise folks.

Jose

Not all of them, we have a EU6500IS that runs nice and quiet.

DaHose wrote:

As to noise question on the HF genny. My Onan 4000 BFA is PLENTY loud when it is running. I can't imagine that the HF units would be a big difference, plus you can add a high rise exhaust (there's a name for that) with an additional silencer inline. Although, I put a spare muffler on the exhaust output of mine out of curiosity and with the exhaust note cut down, I could now hear all the mechanical clacking. Big genny's just plain old make noise folks.

The difference is that the Onan is designed to be enclosed, and can, in fact, be made nearly silent with a properly designed enclosure (I know, I've done it). The HF is designed to run in the free air. Yes, enclosures can be cobbled, but they are somewhat problematic.