Onan issues

Jim,
Depends on the model, if you have a coachman made interior you need to
reset the ac box each time you go from land line to gen.
Should you have the GM model, plug your 50 amp into the receptacle in the
compartment when running off the generator.

> Sorry, yes, I just changed the oil and filter and have triple checked the
> level before and after getting it running. It is right up to the full line.
> And I had just topped off the GMC fuel tanks before starting in on the
> Onan. Breaker button is pushed in. I should probably check that current is
> going through it though as I have heard these can go bad.
>
> Didn't know there was a procedure for changing from shore power to
> generator. Is there something I'm supposed to change?
> --
> -James Palmer, Traverse City, MI
> 1976 Eleganza
>
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--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
Read the manual???? I guess that would have been a smart idea. I actually have been going through it but hadn't gotten to the part about plugging
the cord back in... :roll: As soon as the neighborhood is awake I'll be starting up Mr Onan. Fingers crossed.
--
-James Palmer, Traverse City, MI
1976 Eleganza
 
> It's a GMC body.

James,

If it looks like to GMCs in our Pictures and has TZE vin, then it is a GMC.
That does not make it a GMC coach. Many were sold to outfitters as bare coach bodies (called a Transmode) and how the wiring and other stuff is set
up can be anybody's guess.

If you can still read a model sticker on the font side corners, that can be good. Or, maybe when John Shotwell gets home from this rally, he can help
you figure it out. This is something you should know. There are differences in models and years.

Matt - Still at Mansfield
--
Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
Now with both true Keyless and remote entry
SE Michigan - Twixt A2 and Detroit
 
So, today's report... I have 25 volts on pin 8 (sometimes dropping down to between 24.7 to 24.9). The gen only runs when I have 5 and 9 jumpered,
when I pull pin 12 and try and take the jumper off it promptly dies. (see video) Checked the oil again and I was just a bit under full so I added a
few ounces, regardless, it doesn't seem to be a low oil issue.

I plugged in the cord in the storage area (yeah I'm a newbie) and I do have current inside now. The receptacles don't work (they didn't at the
campground on shore power either so that's a separate issue) but I was able to turn on the AC. The engine seems to be running really weak. It sounds
like it's one chug away from dying which it finally did this morning after running for 10 minutes. I had the AC on when it finally stalled, not sure
if that had anything to do with it since it was already sounding like it was barely hanging on. If it were a lawnmower I would have been looking for
the throttle to rev it up a bit.

Here is a video of it while it was running. What does it sound like to you? At the end I pull pin 12 (hard to see as I was holding the camera) and
then a few seconds later pull pin 5 and it shuts down. I put pin 5 right back on so you can hear the pump. I think I let the pump go too long and
flooded it as it wouldn't start again.

https://www.youtube.com/watch?v=P437AFX4Z-w&feature=youtu.be

The other question I have relates to the power converter inside. A previous owner replaced it with a Diehard Battery Charger. Is this legit? If so,
what setting should I have it on? Automatic vs manual? 2 amp vs 10 amp? I would guess automatic and 10 amp?

--
-James Palmer, Traverse City, MI
1976 Eleganza
 
An inexpensive but relatively effective replacement for the original 12 volt supply. Unless it's a smart charger, keep a close watch on the battery
electrolyte levels.

--johnny

--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.

"Sometimes I wonder what tomorrow's gonna bring when I think about my dirty life and times" --Warren Zevon
 
> So, today's report on the 1976 Eleganza II and it's Onan... I have 25 volts on pin 8 (sometimes dropping down to between 24.7 to 24.9). The gen
> only runs when I have 5 and 9 jumpered, when I pull pin 12 and try and take the jumper off it promptly dies. (see video) Checked the oil again and I
> was just a bit under full so I added a few ounces, regardless, it doesn't seem to be a low oil issue.
>
> I plugged in the cord in the storage area (yeah I'm a newbie) and I do have current inside now. The receptacles don't work (they didn't at the
> campground on shore power either so that's a separate issue) but I was able to turn on the AC. The engine seems to be running really weak. It
> sounds like it's one chug away from dying which it finally did this morning after running for 10 minutes. I had the AC on when it finally stalled,
> not sure if that had anything to do with it since it was already sounding like it was barely hanging on. If it were a lawnmower I would have been
> looking for the throttle to rev it up a bit.
>
> Here is a video of it while it was running. What does it sound like to you? At the end I pull pin 12 (hard to see as I was holding the camera)
> and then a few seconds later pull pin 5 and it shuts down. I put pin 5 right back on so you can hear the pump. I think I let the pump go too long
> and flooded it as it wouldn't start again.
>
> https://www.youtube.com/watch?v=P437AFX4Z-w&feature=youtu.be
>
> The other question I have relates to the power converter inside. A previous owner replaced it with a Diehard Battery Charger. Is this legit? If
> so, what setting should I have it on? Automatic vs manual? 2 amp vs 10 amp? I would guess automatic and 10 amp?
>
> http://www.gmcmhphotos.com/photos/data/500/medium/battery_charger.jpg
If you lift the wire from pin 12, you disable the low oil pressure protection. Since it still wouldn't run without 5 and 9 jumpered, that means it was
not being shut down because the board thinks the oil pressure is low. So now I have to wonder if 24.X volts is enough at pin 8 to tell the board that
the Onan is running.

It sure sounds like it is running slow. Either the fuel pump is not getting enough gas to the carb, or the carb needs cleaning and/or adjustment, or
the governor needs to be adjusted. Save the governor adjustment for another day. Try manually overriding the governor and see if it smooths out and
fires consistently. And be careful not to overrev it with the roof AC on, overrevving causes overvoltage and you can burn up your roof AC unit.

You need to check it for 120VAC output. The slower the engine turns, the lower the voltage, the faster it turns, the higher the voltage. If it lugged
to death trying to power the roof AC. You need to check the voltage without load and under load. When it is set right, the governor will keep the
following:

MAXIMUM NO-LOAD VOLTAGE 126

MINIMUM FULL- LOAD VOLTAGE 110

MAXIMUM NO-LOAD SPEED (RPM) 1890
HERTZ (CURRENT FREQUENCY) 63

MINIMUM FULL-LOAD SPEED (RPM) 1770
HERTZ 59

Once you verify or adjust so that the voltages are correct with and without load, you can recheck the pin 8 voltage and try lifting the jumper.

If the RPMs are right (voltage as described above), and it won't run without pin 5 jumpered to pin 9, I am afraid you might have a bad board.

I wouldn't rule out the possibility you need to clean the carb.

That's about all I have to offer. At home, I get stuff running and let my sister the mechanic do the final tweaking. She is a lot better with small
engine carbs than I am. You probably need the manual and someone with more experience with the Onan to get you over the finish line.

Don't be surprised if it doesn't make 120V anymore. When it shuts down with the roof AC running, it often blows the bridge rectifier. Sorry I should
have told you that before you tried the roof AC. I didn't know it was going to be struggling to run it.

And you need a real 4 stage converter to replace that battery charger before you ruin your house battery.

The manuals are here: http://www.bdub.net/manuals/
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"Highest price does not guarantee highest quality."
 
Forget all of the previous postings about 120 VAC for now. We will get you back on how to fine tune the AC voltage after we get the engine starting
and running properly.

Also the voltage on pin 8 is in the 25 to 30 volt AC range. Not VDC as previously mentioned in another posting. I hope you were reading VAC when
you were there.

On the oil pressure switch. Simply unplugging the switch at the switch or the board will tell the board that the oil pressure is OK.

One of the two above items (pressure Switch circuit or 30 VAC alternator) is not working correctly or you have a bad K2 relay circuit on the board. I
have found a lot of K2s with open coils, blow series diodes, or changed valve resistors and capacitors.

I have fixed my share of those over the years but do not do it any more. At this age, I have more money than time left so I would opt for a new dino
board if the required voltages from the oil pressure switch alternator and board plus +12 and ground and a good fuse are all there.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
> Forget all of the previous postings about 120 VAC for now. We will get you back on how to fine tune the AC voltage after we get the engine
> starting and running properly. ...
Yeah. It is starting, but I am stepping back from the "running properly" process. I won't recommend messing with the governor because it was most
probably correct at the time the RV was "abandoned".

I favor making sure there is no fuel delivery or air/fuel mix trouble before mucking with something that virtually never needs adjustment. I defer to
Onan experts on that.

As far as "forget about the previous postings about 120VAC for now", I say when you get 120VAC, you got the speed right.

The youtube video sounded like it needed more gas, but that might mean it needs more throttle, more fuel from the pump, unplugging carb jets, or
whatever.

Over and out on this thread.
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"Highest price does not guarantee highest quality."
 
I appreciate everyone's help! Last week I had an Onan that wouldn't start and this week it's running and I believe we've isolated the need for a new
or rebuilt board. Still some kinks to be worked out for sure with the fuel delivery one way or another.
--
-James Palmer, Traverse City, MI
1976 Eleganza
 
Inside the carb is a 1/4" O ring that seals the jet tube going in the float bowl. If it isn't sealing it will suck air and not run worth a hoot.

> I appreciate everyone's help! Last week I had an Onan that wouldn't start and this week it's running and I believe we've isolated the need for a
> new or rebuilt board. Still some kinks to be worked out for sure with the fuel delivery one way or another. The carb sure did look clean when I
> opened it up so it's hard for me to believe the issue lies with it. Mr Bridges has been kind enough to offer to look at my board and get it back
> up to snuff so I'll be sending that his way.
>
> And yes, I was measuring the 25 volts as AC.
>
> Sure wish I was at the convention in Ohio. I gave it some serious thought but I found out about it too late and would have had to cancel too many
> things to make it happen.

--
C. Boyd
76 Crestmont
East Tennessee
 
To check If the Onan is not getting enough fuel, the air filter element can
be sprayed with starter fluid while running and if the rpms and smoothness
increase in the presence of starter fluid then you are fuel starved.

Sully
77 eleganza 2
Seattle

> I will double check that, thanks!
> --
> -James Palmer, Traverse City, MI
> 1976 Eleganza
>
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> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
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