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Onan carb nozzle boss gasket [message #258160] Fri, 08 August 2014 06:49 Go to next message
C Boyd is currently offline  C Boyd   United States
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I am having an issue with a 6000k Onan running rich. The books mentions a carb nozzle boss gasket but has no reference in pics or parts book. The screen is also missing from the bowl. What does the gasket look like and where does it go?

C. Boyd
76 Crestmont
East Tennessee
Re: Onan carb nozzle boss gasket [message #258168 is a reply to message #258160] Fri, 08 August 2014 10:48 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
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C Boyd wrote on Fri, 08 August 2014 06:49
I am having an issue with a 6000k Onan running rich. The books mentions a carb nozzle boss gasket but has no reference in pics or parts book. The screen is also missing from the bowl. What does the gasket look like and where does it go?


From 2012 post by Woody...

quote..
For those of you still nursing the onan, thought I'd share a lesson learned.

After 3 years of my 6K onan sitting on the garage floor (installed a Generac 55 in the MH), finally got around to prepping the old beast for use at the cabin. Decarbonized the heads, cleaned and checked everything, and built a cart out of some scrap steel and some HF wheels per the photos Davem posted. She fired to life again but for the life of me, couldn't get her to lean out without unplugging the fuel pump. Must've opened up the carb a dozen times to adjust/check everything.

Figured the carb was just worn out and was on the verge of ordering a rebuild kit from Jim K, and noticed in the photo on his website a fat, round gasket I hadn't seen during the dozen disassemblies of my carb. The diagram on page 13 of the manual, as well as my malfunctioning carb, doesn't have this gasket. Guess I dropped mine on the floor during disassembly and it rolled into that Murphy place, and upon reassembly of course I followed the schematic and it made sense since the marks on the bowl screen looked to match up with the nozzle boss.

It was only by referring to the Fuel System Trouble Diagnosis for smokes and runs rich, that the "nozzle boss gasket" is mentioned. Doph...all that fuel is sucked straight into the nozzle, bypassing the hi power jet. So I made a temp gasket from thick immersion safe thick gasket material and inserted it in the bowl between the filter screen and the nozzle boss. She runs like new now and I've just ordered the parts to convert it tri-fuel capable for the outpost.

Moral to the story, don't rely exclusively on any manual...take pictures with your cell phone of each step of disassembly, so if CRS hits you like it hits me a lot, you can put it back together the way it came apart. Also, do all those graveyard onan's have more untold secret fixes up their sleeves? It is one tough machine and might deserve a second look if you've got one you're using a doorstop. FWIW. Woody.

end quote...


Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: Onan carb nozzle boss gasket [message #258176 is a reply to message #258168] Fri, 08 August 2014 12:03 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Dennis S wrote on Fri, 08 August 2014 10:48
From 2012 post by Woody...

quote..
was on the verge of ordering a rebuild kit from Jim K, and noticed in the photo on his website a fat, round gasket I hadn't seen during the dozen disassemblies of my carb. ...
Is the nozzle boss gasket shown in this picture? Which gasket is it?

http://www.appliedgmc.com/products/892.jpg
Re: Onan carb nozzle boss gasket [message #258181 is a reply to message #258176] Fri, 08 August 2014 12:39 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
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A Hamilto wrote on Fri, 08 August 2014 13:03
Dennis S wrote on Fri, 08 August 2014 10:48
From 2012 post by Woody...

quote..
was on the verge of ordering a rebuild kit from Jim K, and noticed in the photo on his website a fat, round gasket I hadn't seen during the dozen disassemblies of my carb. ...
Is the nozzle boss gasket shown in this picture? Which gasket is it?

http://www.appliedgmc.com/products/892.jpg



I don't believe it is unless it is stacked under the bowl screw gsk. My kit did not have it or it is hiding somewhere. It is the same dia but is suppose to be thicker. I ended up using 2 bowl gaskets on the inside and 1 out. It is purring now for a few minutes then acts up some but getting closer. Could be plugs or points. Runs bout the same under load or not. Still could be fuel issue with my home made gaskets.


C. Boyd
76 Crestmont
East Tennessee
Re: Onan carb nozzle boss gasket [message #258185 is a reply to message #258181] Fri, 08 August 2014 13:29 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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C Boyd wrote on Fri, 08 August 2014 12:39
I don't believe it is unless it is stacked under the bowl screw gsk. My kit did not have it or it is hiding somewhere. It is the same dia but is suppose to be thicker. I ended up using 2 bowl gaskets on the inside and 1 out. It is purring now for a few minutes then acts up some but getting closer. Could be plugs or points. Runs bout the same under load or not. Still could be fuel issue with my home made gaskets.
The bigger picture looks like there is a gasket stacked like you say, but imbedding that picture messes up the forum (widens the page).
Re: Onan carb nozzle boss gasket [message #258189 is a reply to message #258185] Fri, 08 August 2014 14:10 Go to previous messageGo to next message
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[Updated on: Tue, 27 January 2015 19:24]

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Re: Onan carb nozzle boss gasket [message #258191 is a reply to message #258189] Fri, 08 August 2014 14:33 Go to previous messageGo to next message
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[Updated on: Tue, 27 January 2015 19:23]

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Re: Onan carb nozzle boss gasket [message #258193 is a reply to message #258191] Fri, 08 August 2014 15:07 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
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The rubber washer with the little hole is thinner than the paper bowl gasket. I got no idear where it goes. Rubber don't do good in this environment. The big bowl gasket was rubber in the kit and it rolled and swelled up first time I had it back off. I am having to use the original. The gasket I need goes under the screen that I don't have either and probably is paper composite. Jerry called and said he had o rings for gas and would bring them by. We are thinkin that should work. It runs now, purrs most of the time but flutters some. Inside voltage 120 - 125 with ac on.



JoeC wrote on Fri, 08 August 2014 15:33
Here is an interesting link to a 146-0180 Repair Kit on e-bay.

http://www.ebay.com/itm/REPAIR-rebuild-KIT-WALBRO-LMB-ONAN-146-0180-CLINTON-/130309446769

If I am counting correctly, it looks like it has another gasket in it which may be the missing Boss Gasket. Doesn't the real fat black one look like it would fit over the end of the Nozzle?



C. Boyd
76 Crestmont
East Tennessee
Re: Onan carb nozzle boss gasket [message #258198 is a reply to message #258193] Fri, 08 August 2014 16:01 Go to previous messageGo to next message
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[Updated on: Tue, 27 January 2015 19:23]

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Re: Onan carb nozzle boss gasket [message #258284 is a reply to message #258198] Sat, 09 August 2014 14:55 Go to previous message
C Boyd is currently offline  C Boyd   United States
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Update.. went back in the carb and put a green o ring around the bowl screw inside instead of the homemade used gaskets and the only place the flat rubber washer with the little hole would go is in between the bowl securement bolt and the nozzle. It fired right up and purred then started acting up a little. Set the points at 20 and it is purring nicely. Makes electricity and everstuff. So don`t give up they can be repaired.





JoeC wrote on Fri, 08 August 2014 17:01
Chuck, at least yours makes electricity and the voltage sounds about right. Mine didn't run or make electircity two months ago when I started working on it. Not is runs good and makes electricity. My field coils were shorted out and I got a rewound assembly from Jim Miller.

When you say "flutters" - do you mean it "pulses" and the governor arm moves with the pulses? That could be several things but I would lub all the connection points - if you have not already done so. You also might want to look at the Sensitivity Ajustment on Page 27 of the Major Service Manual. There is a discussion there about "hunting". JM2C

I hope you solve your issues. Please post what you find for us to know your final resolution. Thanks



C. Boyd
76 Crestmont
East Tennessee
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