generator carb cleaning and adjustment

Keith V

Keith V

Well-known member
Mar 26, 2008
3,604
399
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Got my generator running, it's a newer Onan Emerald not the OEM one. The carb and puel pump were pretty gummed up.

It runs pretty good but surges. It has an altitude adjustment that I definitly screwed up, anyone know how to set that?

Big question is how to clean the carb, pulling the carb looks to be a nightmare as it's really packed in there and NOT on a slide like the OEM one.

Is seafom worth trying or should I just bite the bullet and pull the thing out?

How would one use said seafom on a genny? I'm thinking put some in a small gas can, with gas of course, and run from it for a while?

Thanks!
 
Keith, You might try Seafoam (or some other gas additive) in your gas tank. It will help to clean up the coach engine too. It might be effective at
cleaning the internal parts of the carburetor. A spray carb cleaner might be your best bet for cleaning the the venturi and parts where the air flows
through, as well as the external parts of the carb. Spray it in the carb intake while the engine is running and stop if it starts to stall. Probably
a good idea to disconnect the electrical plug because it will surge quite a bit during this process.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging
 
Keith, if you have a Mercury Marine dealer near where you are, stop there
and pick up two things. One is a carb cleaning spray can, I don't have a
part number. The other is a product called "marine engine fogging oil",
also in a spray can. Both are time tested high quality products. I have
used both of them for years. Read the labels, follow their
recommendations. JWIWD.
JIM HUPY
SALEM, OR
78 GMC ROYALE 403

> Keith, You might try Seafoam (or some other gas additive) in your gas
> tank. It will help to clean up the coach engine too. It might be
> effective at
> cleaning the internal parts of the carburetor. A spray carb cleaner might
> be your best bet for cleaning the the venturi and parts where the air flows
> through, as well as the external parts of the carb. Spray it in the carb
> intake while the engine is running and stop if it starts to stall. Probably
> a good idea to disconnect the electrical plug because it will surge quite
> a bit during this process.
> --
> Carl Stouffer
> '75 ex Palm Beach
> Tucson, AZ.
> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive,
> Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American
> Eagles,
> Solar battery charging
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Ive used Mercury Marine (quicksilver) Power Clean on a few outboards. Follow the directions as stated. Worked well for engines that get used for a
few months then go dormant for a few months. If you can spray it in the carb throat and let it sit while the engine is off but hot for a few hours.
Should help to clean up the junk without having to remove the carb.

I had an outboard that would not idle well after it sat for 10 years. Got it started and used the power clean and it worked pretty well. I too did
not want to remove the carb if I didnt have to.
--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan
 
Cool I'm sure theres a Mercury dealer around here, I'll give it a shot.

________________________________
From: Gmclist on behalf of Wayne Rogewski
Sent: Monday, March 20, 2017 3:20:13 PM
To: gmclist
Subject: Re: [GMCnet] generator carb cleaning and adjustment

Ive used Mercury Marine (quicksilver) Power Clean on a few outboards. Follow the directions as stated. Worked well for engines that get used for a
few months then go dormant for a few months. If you can spray it in the carb throat and let it sit while the engine is off but hot for a few hours.
Should help to clean up the junk without having to remove the carb.

I had an outboard that would not idle well after it sat for 10 years. Got it started and used the power clean and it worked pretty well. I too did
not want to remove the carb if I didnt have to.
--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan

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I'd concentrate on the fuel supply line for kinks, porosity and splits. Mine split where it stretced over the pump barb. Almost invisible but sucking
air giving your symptoms. I don't like Seafoam BS. Gasoline is a solvent with refinery added cleaners and additives.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Keith,
Before you get it out of there, look closely at the attachment of the bellcrank on the throttle shaft. I bought a used Emerald and had to clean the
carb to make it run, but it still surged with or without a load. Fortunately, I noticed the slop in the bellcrank attachment to the shaft before I got
something really maladjusted. An automatic center punch on that shaft swelled the shaft end, tightening the bellcrank attachment, and the surge was
fixed.
--
Terry Kelpien

ASE Master Technician

73 Glacier 260

Smithfield, Va.
 
I'll inspect the bellcrank, it seems to me this thing surged before, but I'm paying attention now...

The fuel lines are all new and steel except for the last 6" I guess I should take a looksee at that too

________________________________
From: Gmclist on behalf of Terry
Sent: Monday, March 20, 2017 10:52:21 PM
To: gmclist
Subject: Re: [GMCnet] generator carb cleaning and adjustment

Keith,
Before you get it out of there, look closely at the attachment of the bellcrank on the throttle shaft. I bought a used Emerald and had to clean the
carb to make it run, but it still surged with or without a load. Fortunately, I noticed the slop in the bellcrank attachment to the shaft before I got
something really maladjusted. An automatic center punch on that shaft swelled the shaft end, tightening the bellcrank attachment, and the surge was
fixed.
--
Terry Kelpien

ASE Master Technician

73 Glacier 260

Smithfield, Va.

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I've seen this looseness on Onans ion SOBs several times.. one even fell off. Onan wanted to sell the owner a complete new carb for several hundred
bux. We managed to stake it back on so it stayed and was tight long enough for the epoxy to set up.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
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