Go Back   iRV2 Forums > MOTORHOME FORUMS > MH-General Discussions & Problems
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
Thread Tools Search this Thread Display Modes
Old 11-20-2009, 07:43 AM   #1
Junior Member
Join Date: Jul 2009
Posts: 17
Onan Generator question

HI i have question on my Onan Generator. after starting generator what
would cause it to surge while running ? instead a smooth idle greyhawk


greyhawk is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 11-20-2009, 07:57 AM   #2
Senior Member
Ford Super Duty Owner
Join Date: Mar 2009
Posts: 360
Check the altitude adjustment. Mine moves on it's own and when it starts surging I have to re-adjust it.

zippo is offline   Reply With Quote
Old 11-20-2009, 07:58 AM   #3
Junior Member
Ratman's Avatar
Join Date: Aug 2009
Posts: 8
I have an older 4K Onan and recently had a surging problem. I found two problems. First there are two adjustment mixture screws. The "back" one was missing a small o ring. I replaced that and it seemed to run better for a while. Again it started to surge. This time I removed the entire carb (Note - It is easier to just pull the entire intake manifold with the carb attached than to try to disassemble the parts in the bay - At least it worked for me). I then checked the float valve and found a bunch of crap under the seat. Flushed it out and reassembled and now it purrs...

Good luck
Ratman is offline   Reply With Quote
Old 11-20-2009, 04:30 PM   #4
Senior Member
doc's Avatar
Appalachian Campers
Join Date: Sep 2002
Location: Dixie !! (north Georgia) USA
Posts: 3,022
Fuel filter trying to clog??
doc is offline   Reply With Quote
Old 11-20-2009, 05:32 PM   #5
Senior Member
Gary - K7GLD's Avatar
Join Date: Aug 2009
Posts: 1,696
My 4kw Onan does that if the altitude (mixture) screw on the bottom of the float bowl is set too lean - for too high an altitude. Try turning it a bit at a time towards the lower altitude direction - mine smooths right out and puuuuuurs like a kitten when adjusted properly.

Along those lines, especially for generators and other smaller gas engines that only run occasionally, then sit idle for long periods of time - that tends to allow fuel sitting in the carb float bowl and up in the jets, to turn into a varnish-like material that's pretty much impossible to remove without completely dis-assembling the carb.

Do your gensets, lawnmowers and other small engines a break, and either RUN them occasionally long enough to come up to normal temperature - and/or treat the fuel with Stabil fuel conditioner to extend the life of the fuel. It's LOTS easier, cheaper, and less frustrating than trying to correct problems AFTER the damage has been done!
John Day....|'88 Winnebago Super Chief 27ft. Class A
Eastern .....|'88 KIT model 240 24 ft. 5er
Oregon ......|'02 Dodge/Cummins 2500 Quad Cab
Gary - K7GLD is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Onan 5.5 Marquis gold gas, shuts down at 15 min Shamong Shepherds MH-General Discussions & Problems 12 08-27-2008 05:39 PM
Onan Generator Quits On Start With No Load Birddog Pilot Alpine Coach Owner's Forum 26 08-11-2008 10:49 AM
Onan Problems Stretch Alpine Coach Owner's Forum 12 06-23-2005 06:02 PM
High dollar ONAN Quiet Diesel not worth it! Dale Tomlinson Winnebago Industries Owner's Forum 2 05-17-2005 06:24 PM
Finally fixed my Onan 3600LP shut-down problem. Ken Lenger RV Systems & Appliances 8 04-20-2005 05:25 PM

» Featured Campgrounds

Reviews provided by

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 04:14 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.