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Onan Carb [message #285140] Sun, 16 August 2015 17:26 Go to next message
Luvn737s is currently offline  Luvn737s   United States
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I am running an Emerald III 6.5Kw Onan. When it's running that is. I have to constantly clean the carb after which it runs fine for about 2 hours then starts hunting and then quits altogether. Do you know anyone who does Onan carb rebuilds or exchanges? I could probably do it myself, but I know nothing about this unit and would prefer to start fresh.

Randy
1973 26' Painted Desert
Ahwatukee (Phoenix) AZ
Re: Onan Carb [message #285166 is a reply to message #285140] Sun, 16 August 2015 21:17 Go to previous messageGo to next message
thainglo is currently offline  thainglo   United States
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Randy - I had great success directly with Walbro. I'm assuming that is the manufacturer of your carb. Call Luis Salas and give him the model of your carb. Mine was LMB for the 6k. Was $50, worked great and took about 10 days.

Matt Sladek 1976 Eleganza II Coralville, IA
Re: Onan Carb [message #285180 is a reply to message #285166] Mon, 17 August 2015 00:52 Go to previous messageGo to next message
bhayes is currently offline  bhayes   United States
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thainglo wrote on Sun, 16 August 2015 20:17
Randy - I had great success directly with Walbro. I'm assuming that is the manufacturer of your carb. Call Luis Salas and give him the model of your carb. Mine was LMB for the 6k. Was $50, worked great and took about 10 days.


You'll want to verify it's a carburetor problem. Some of the more knowledgeable generator brains on this list can chime in on what to look for. Do you have a service manual? The manual should tell you what the settings are for your carburetor.

If it is a carb problem, you'll need to find out the manufacturer of your specific carburetor. Onan has used a few manufacturers over the years, including Walbro and Nikki. If your carb is a Nikki, you may want to call around to local small engine/lawnmower shops in your area. They may be able to do a rebuild for you.

If it's a Walbro, I went directly through Luis at Walbro as well. I think my rebuild was a bit more ($80-$90 IIRC), but they did a great job. They even sent a printout with everything they found wrong that they fixed.

Since your Onan is an Emerald, new carbs are probably still available through Onan or a reseller, though probably more pricey than a rebuild.




Bryan Hayes
'76 Eleganza II
Salt Lake City, Utah
Re: Onan Carb [message #285201 is a reply to message #285140] Mon, 17 August 2015 09:39 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Randy,

I have to suggest that what you have is not really a carburetor problem. I suggest this even though I am not sure what it is......
There are three guesses that are at the top of my list.
First would be is the air filter sound. If you are sucking in crud, that can stop an tiny carburetor up real fast.
The simplest would be fuel contamination. Get a lawn mower size fuel filter and put it in line. If it stays running, you got it.
The last, but not highly likely would be oil carry-over from the crankcase vent system. To check this one out, take the hose off where it connects to the intake and plug the hole in the intake. Be ready to catch "blow-over" and see if it doesn't do better. If this is the issue, you will know pretty fast. What to do about it is another issue.

Good Luck

Matt


Luvn737s wrote on Sun, 16 August 2015 18:26
I am running an Emerald III 6.5Kw Onan. When it's running that is. I have to constantly clean the carb after which it runs fine for about 2 hours then starts hunting and then quits altogether. Do you know anyone who does Onan carb rebuilds or exchanges? I could probably do it myself, but I know nothing about this unit and would prefer to start fresh.



Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Onan Carb [message #285519 is a reply to message #285140] Fri, 21 August 2015 01:02 Go to previous messageGo to next message
Luvn737s is currently offline  Luvn737s   United States
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My guess is that it ethanol related and when I dropped the bowl it was pretty cruddy. This genset wasn't pampered and I got it pretty cheaply so even if I put a carb on it I think I'm still money ahead. I like it much better than the Kohler I had.

Randy
1973 26' Painted Desert
Ahwatukee (Phoenix) AZ
Re: Onan Carb [message #285540 is a reply to message #285140] Fri, 21 August 2015 11:23 Go to previous message
rscortezzo is currently offline  rscortezzo   United States
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I bought a Walbro lmb 180 on eBay for 39.00 could not find a power needle for the original carb. With help from Gene Fisher and Gary Bovee's help the Onan runs great, also installed Gary's electronic ignition. Also I have plenty of AC power.

Rich Cortezzo
Green Valley AZ
1978 Eleganza II F389018
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