Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  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 06-20-2011, 07:21 PM   #1
Junior Member
 
Join Date: Jun 2011
Location: Belgrade, MT
Posts: 11
Onan BS series generator

Hi everyone! I'm looking for a little direction. I inherited this BEAUTY from my in-laws who left it sitting in a field for 7 years! I've been whittling thru a seemingly endless list of things to do to her so she is 'camp-able'. We're not too far from that but now I'm in a quandary trying to get this generator to stay running. It will start and run for about 15 seconds and then shut down....every time.

I've read some threads that have given a list of a few things to check, so here is what I've done.

The oil was very thin so I changed with with SAE 30.

I've read about the oil pressure sending unit, and I removed the lead wire (for just a short time)I to see if I got a different reaction and didn't.

I removed the manifold and cleaned out the carb twice...also checked that the float level was at 1/4" as my owner's manual states.

I have fiddled with the idle mixture setting and fuel mixture valve a lot...to no avail.

I heard that if there is a leak in the fuel line even before the fuel pump, that it could cause problems so I stuck a tube directly in a gas can with no change.

I put a new fuel pump on it (4-6 psi) and an inline filter.

I don't know what else to do or check so I am looking for some advice.

Thanks in advance for your help!

Jeremy
__________________

__________________
jerm8 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 06-20-2011, 07:32 PM   #2
Moderator Emeritus
 
Mike Canter's Avatar


 
Join Date: Apr 2008
Location: Freeport, ME
Posts: 4,707
Will it start right up again and run for another 15 seconds or do you have to wait?
__________________

__________________
Mike Canter
"Gunner" USN Retired, Airdale
2004 Monaco Signature 44' Conquest. Detroit 60
Mike Canter is offline   Reply With Quote
Old 06-20-2011, 11:11 PM   #3
Junior Member
 
Join Date: Jun 2011
Location: Belgrade, MT
Posts: 11
It starts right up immediately and runs for another 15 seconds.
__________________
jerm8 is offline   Reply With Quote
Old 06-22-2011, 06:18 PM   #4
Senior Member
 
Ford Super Duty Owner
Join Date: Dec 2009
Location: Mcdonough, Ga.
Posts: 4,383
Quote:
Originally Posted by jerm8 View Post
Hi everyone! I'm looking for a little direction. I inherited this BEAUTY from my in-laws who left it sitting in a field for 7 years! I've been whittling thru a seemingly endless list of things to do to her so she is 'camp-able'. We're not too far from that but now I'm in a quandary trying to get this generator to stay running. It will start and run for about 15 seconds and then shut down....every time.

I've read some threads that have given a list of a few things to check, so here is what I've done.

The oil was very thin so I changed with with SAE 30.

I've read about the oil pressure sending unit, and I removed the lead wire (for just a short time)I to see if I got a different reaction and didn't.

I removed the manifold and cleaned out the carb twice...also checked that the float level was at 1/4" as my owner's manual states.

I have fiddled with the idle mixture setting and fuel mixture valve a lot...to no avail.

I heard that if there is a leak in the fuel line even before the fuel pump, that it could cause problems so I stuck a tube directly in a gas can with no change.

I put a new fuel pump on it (4-6 psi) and an inline filter.

I don't know what else to do or check so I am looking for some advice.

Thanks in advance for your help!

Jeremy
It may be flooding. I went to school on the onan in 93, so its been a while. I am almost positive the pressure should be 2 PSI
__________________
1998 Pace Arrow 35 ft. F53 Ford V10 2012 Honda Civic toad
32 years mechanic at Delta Air Lines 15 year motorhome service manager. 3 popups....2 travel trailers....5 motorhomes....loved them all.
ga traveler is offline   Reply With Quote
Old 06-22-2011, 07:27 PM   #5
Junior Member
 
Join Date: Jun 2011
Location: Belgrade, MT
Posts: 11
Do you think it's too much of a pump? Would it start right away again if it were flooding?

Also, It's a BF series generator, not BS. I guess you know where my mind was regarding this thing when I first posted!
__________________
jerm8 is offline   Reply With Quote
Old 06-22-2011, 10:05 PM   #6
Senior Member
 
bigskymt's Avatar
 
Newmar Owners Club
Join Date: Apr 2010
Posts: 462
jerm8: greetings from Whitehall.
The wire you removed from the oil sending unit provides a ground ( "- VDC" with proper oil pressure) for both the fuel pump and primary voltage to ignition relay coils. Try disconnecting that wire and grounding it to the generator chassis to eliminate the oil pressure switch.
If it were flooding it throw out a lot of black smoke and be hard to re-start.
__________________
bigskymt is offline   Reply With Quote
Old 06-22-2011, 11:09 PM   #7
Junior Member
 
Join Date: Jun 2011
Location: Belgrade, MT
Posts: 11
I did not have it grounded when I disconnected it...it was just hanging there. I'll give it a try tomorrow. Thanks for the tip, neighbor!
__________________
jerm8 is offline   Reply With Quote
Old 06-23-2011, 07:31 AM   #8
Junior Member
 
Join Date: Jun 2011
Location: Belgrade, MT
Posts: 11
Houston, we've got a problem. The electric choke assembly came out and arc'd against the chassis while it was started. It is missing a screw. (did I mention that this thing has been sitting for a while, and before that it was not taken care of very well)

Do you think I fried something? Now it won't start like it did. It only coughs and backfires.

Yikes!
__________________
jerm8 is offline   Reply With Quote
Old 06-23-2011, 08:06 AM   #9
Moderator Emeritus
 
Mike Canter's Avatar


 
Join Date: Apr 2008
Location: Freeport, ME
Posts: 4,707
Yep, you fried something. You have lost your cold start enrichment. The cough and spit back is caused by excessive leaness on the start. Your electric choke is not coming on for start. Check to see if you still have 12 volts at the wire that you shorted out. If no voltage them hopefully a fuse.
__________________
Mike Canter
"Gunner" USN Retired, Airdale
2004 Monaco Signature 44' Conquest. Detroit 60
Mike Canter is offline   Reply With Quote
Old 06-23-2011, 01:10 PM   #10
Senior Member
 
bigskymt's Avatar
 
Newmar Owners Club
Join Date: Apr 2010
Posts: 462
The electric choke works with 12vdc to the coil and the mounting plate grounding to the choke housing. There are I believe 3 screws that attach the plate to the housing. If the screws are loose you will not get a good ground and the choke will not release as the current heats the choke coil and pulls off the choke.
If you reinstalled the choke coil and didn't engage the coil with the choke linkage you will have no choke and hard starting.
Since the heating coil is in itself a resistor I doubt you did any damage when it touched ground. If the choke plate touched ground it would arc as the circuit was completed.
If you have a test light you can check voltage at that wire if you get it running.
You can manually activate the choke to aid in starting.
__________________
bigskymt is offline   Reply With Quote
Old 06-23-2011, 11:49 PM   #11
Junior Member
 
Join Date: Jun 2011
Location: Belgrade, MT
Posts: 11
The wire from the oil pressure switch still has juice. I put the electric choke back together and it started up again. It still shuts down after about 15 seconds. I tried pulling the wire off and grounding it at start up but it would not fire. It fires with the wire connected, or disconnected (but dangling). It still shuts down either way after about 15 seconds and will start right up again.

The engine seems to run real smooth until it shuts down; no black smoke, no backfiring any more.

Could the culprit still be the oil pressure switch, but I'm just not testing it right?
__________________
jerm8 is offline   Reply With Quote
Old 06-24-2011, 09:13 AM   #12
Moderator Emeritus
 
Gary RVRoamer's Avatar


 
Join Date: Jan 2000
Location: Silver Springs, FL. USA
Posts: 18,084
Some Onans will shut down if there is no electrical output. Guess they figure if no power is being produced, something must be wrong with the stator or armature and they want to quit ASAP. Maybe that's your problem???
__________________
Gary Brinck
Former owner of 2004 American Tradition
Home is in the Ocala Nat'l Forest near Ocala, FL
Summers in Black Mountain, NC
Gary RVRoamer is online now   Reply With Quote
Old 06-24-2011, 11:35 AM   #13
Senior Member
 
bigskymt's Avatar
 
Newmar Owners Club
Join Date: Apr 2010
Posts: 462
Gary RVRoamer may have hit on the answer.
As for the oil pressure switch the system doesn't look at that when cranking as w/o the engine running you have no oil pressure (or very little once its been cranking for awhile). My schematics don't show the oil pressure switch as a resistance value but your description seems to indicate that by your results when grounding the wire.
The fact that it always runs 15 seconds seems to further rule out the oil pressure switch since that switch is responsible for both primary ignition voltage and fuel pump voltage. You can test that by removing the wire from the switch within the 15 sec. run time and see if it immediately stops.
You can also put a test lamp on the wire going to the electric fuel pump
within the 15 sec. run time and see if you lose voltage there just before it quits. (I would expect you would). That will indicate if the run relay is dropping off prior to it stopping.
Last if you can measure the 115vac output within the 15 sec. run time.
good luck
__________________
bigskymt is offline   Reply With Quote
Old 06-25-2011, 05:38 PM   #14
Junior Member
 
Join Date: Jun 2011
Location: Belgrade, MT
Posts: 11
I pulled the oil pressure switch wire as it was running and it didn't shut down. It will start fine with the wire disconnected, just not when it is grounded.

It appears that there is power output from the generator. I'm getting a little over 120V at the breaker in the gen set compartment.

I put my test lamp on the fuel pump wire while it was running. The lamp didn't shut off prior to the engine quitting, but simply faded as it lost rpms as the engine was quitting. (I tried it a couple times with the same results)

I don't know if it is related, but I'm not getting juice inside to the outlets or a/c when it is running. The outlets, etc. work fine when I have it plugged in to the house. The breakers are all on and the fuses seem to be fine. It seems like something needs to kick in after the generator starts, but nothing happens inside with power. Maybe it isn't running long enough. I don't know.
__________________

__________________
jerm8 is offline   Reply With Quote
Reply

Tags
generator, onan



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 generator help MACRacing Monaco Owner's Forum 8 07-12-2010 06:14 PM
Onan propane generator surging Papa_Jim MH-General Discussions & Problems 4 07-11-2010 09:14 AM
Generator Question - Propane Onan Suddenly Misfiring...... RBAJJK Spartan Motorhome Chassis Forum 1 08-04-2009 09:00 PM
onan generator clicking noise peter griffin Winnebago Industries Owner's Forum 10 02-23-2009 02:48 PM
Onan Generator Problem jadams RV Systems & Appliances 2 03-30-2007 03:52 AM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 06:04 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.