Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
RV Trip Planning Discussions

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.
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 08-30-2018, 07:50 AM   #1
Senior Member
 
BrokeDown's Avatar
 
Join Date: Mar 2016
Location: Fort Myers, FL
Posts: 604
Onan 10K Fuel Pump Wiring

I am having a problem where my Onan 10K shuts down with a 3-6 code. Sometimes it will run for 2 or 3 hours, sometimes it will run for 15 minutes and sometimes it will not run at all.

I was told that this is most likely a fuel problem so we replaced most of what is cheap to replace (air filter, fuel filter, fuel pump, etc.) I still get the random shutdowns.

I had an Onan Tech install the new fuel pump. He said that if that did not fix the problem, he would replace the control board next.

I am not 100% convinced that the control board is the problem. It could be a fuel line problem or a fuel pickup problem.

To isolate the problem, I am going to run a separate 12V+ line to the fuel pump. If it solves the problem, the problem is most likely the control board or the relay. If it does not solve the problem, it is most likely the fuel lines or pickup.

I have a couple of questions.

1. The fuel pump has a black and white lead, each lead is one wire. I assume white is 12+?

2. The leads coming from the generator has 2 wires each. Is one start and one run? Do I need both for this test?

3. Does the negative lead go to ground or is it switched too?

Thanks for any help that you can provide.


-B
__________________
Full time RVer since 4/2016. Newmar Mountain Aire 4523 - Jeep Rubicon - Harley FLTCR - 2022 F450 Platinum, 2022 Momentum 351MS-R with Curt Flex Air hitch and MORryde IS - Also considering a Polaris General 4 Seater and a Can Am Spyder RT
BrokeDown 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 08-30-2018, 12:53 PM   #2
Senior Member
 
Monaco Owners Club
Join Date: Sep 2014
Posts: 4,569
You should be able to find the service manual and schematics here;

Index of /~n0nas/manuals/onan
__________________
1996 Tioga Class C
2007 Monaco Diplomat 40 PDQ
TOAD 2012 Cadillac SRX 4
okcnewbie is offline   Reply With Quote
Old 08-30-2018, 01:12 PM   #3
Senior Member
 
bruceisla's Avatar
 
Join Date: Oct 2012
Location: Foley AL
Posts: 7,138
Quote:
Originally Posted by okcnewbie View Post
You should be able to find the service manual and schematics here;

Index of /~n0nas/manuals/onan



Look near the end of index ... HDKCA thru HDKCD service manual. doc number 981-0540B
__________________
2005 Newmar Essex 4502, 2013 Caddy SRX
1997 HR Endeavor 37, CAT, 1996 Geo Tracker
bruceisla is offline   Reply With Quote
Old 08-30-2018, 02:15 PM   #4
Community Administrator
 
Lt Dan's Avatar


 
Tiffin Owners Club
Join Date: Sep 2013
Location: DFW, Texas
Posts: 21,263
Also, be aware that some coach builders buried a second fuel filter in the line between the fuel tank and the generator. Some have reported this filter being bundled inside a wiring harness so you may have to trace the line all the way from the tank to the generator.
__________________
2017 Phaeton 40IH XSH Maroon Coral - Power Glide Chassis with IFS
Previous '15 Tiffin Allegro RED 38QRA and '06 Itasca Sunrise 35A
'16 Jeep JKU Wrangler Sahara or '08 Honda Goldwing
Lt Dan is offline   Reply With Quote
Old 08-30-2018, 07:15 PM   #5
Senior Member
 
BrokeDown's Avatar
 
Join Date: Mar 2016
Location: Fort Myers, FL
Posts: 604
Quote:
Originally Posted by okcnewbie View Post
You should be able to find the service manual and schematics here;

Index of /~n0nas/manuals/onan



Thanks. I have the service manual.



The schematics only show one positive and one negative going to the fuel pump. The wire harness shows 2 wires but there is no way to tell where they go.....


I'll try hooking a wire from 12V+ terminal to a switch and another wire from the switch to the pump + lead.


If it works, I just may put a relay inline and leave it that way. We don't use the generator that often and its not worth $700 for a new control board when a few dollars worth of wire and a switch can take care of it (assuming that it does.)


-B
__________________
Full time RVer since 4/2016. Newmar Mountain Aire 4523 - Jeep Rubicon - Harley FLTCR - 2022 F450 Platinum, 2022 Momentum 351MS-R with Curt Flex Air hitch and MORryde IS - Also considering a Polaris General 4 Seater and a Can Am Spyder RT
BrokeDown is offline   Reply With Quote
Old 08-31-2018, 04:30 AM   #6
Senior Member
 
bruceisla's Avatar
 
Join Date: Oct 2012
Location: Foley AL
Posts: 7,138
Quote:
Originally Posted by BrokeDown View Post
Thanks. I have the service manual.



The schematics only show one positive and one negative going to the fuel pump. The wire harness shows 2 wires but there is no way to tell where they go.....


I'll try hooking a wire from 12V+ terminal to a switch and another wire from the switch to the pump + lead.


If it works, I just may put a relay inline and leave it that way. We don't use the generator that often and its not worth $700 for a new control board when a few dollars worth of wire and a switch can take care of it (assuming that it does.)


-B

And you can try running the gen from a bucket of diesel as a test.
__________________
2005 Newmar Essex 4502, 2013 Caddy SRX
1997 HR Endeavor 37, CAT, 1996 Geo Tracker
bruceisla is offline   Reply With Quote
Old 08-31-2018, 12:47 PM   #7
Senior Member
 
BrokeDown's Avatar
 
Join Date: Mar 2016
Location: Fort Myers, FL
Posts: 604
Quote:
Originally Posted by bruceisla View Post
And you can try running the gen from a bucket of diesel as a test.

If the direct wire test does not fix it, this would be my next step.
-B
__________________
Full time RVer since 4/2016. Newmar Mountain Aire 4523 - Jeep Rubicon - Harley FLTCR - 2022 F450 Platinum, 2022 Momentum 351MS-R with Curt Flex Air hitch and MORryde IS - Also considering a Polaris General 4 Seater and a Can Am Spyder RT
BrokeDown is offline   Reply With Quote
Old 08-31-2018, 07:38 PM   #8
Junior Member
 
Join Date: Aug 2015
Posts: 9
Quote:
Originally Posted by BrokeDown View Post
If the direct wire test does not fix it, this would be my next step.
-B
Make sure the oil level is correct. Believe it or not, too much oil can cause this same problem! I had to drain about4 ounces. Has worked perfectly since!
__________________
!991 Fleetwood Bounder 31K
mlj824 is offline   Reply With Quote
Old 09-01-2018, 06:52 AM   #9
Senior Member
 
BrokeDown's Avatar
 
Join Date: Mar 2016
Location: Fort Myers, FL
Posts: 604
Quote:
Originally Posted by mlj824 View Post
Make sure the oil level is correct. Believe it or not, too much oil can cause this same problem! I had to drain about4 ounces. Has worked perfectly since!

Interesting. I will check that. Did you get a 36 error code?


-B
__________________
Full time RVer since 4/2016. Newmar Mountain Aire 4523 - Jeep Rubicon - Harley FLTCR - 2022 F450 Platinum, 2022 Momentum 351MS-R with Curt Flex Air hitch and MORryde IS - Also considering a Polaris General 4 Seater and a Can Am Spyder RT
BrokeDown is offline   Reply With Quote
Old 09-03-2018, 12:27 AM   #10
Senior Member
 
Gulf Streamers Club
Ford Super Duty Owner
Join Date: Aug 2015
Location: Memphis, TN
Posts: 4,308
Just be careful bypassing the CB/ relay, because if it continues to run w/ gen shut down, it can overpower the float needle and could cause a flooded engine, and/ or worse, fuel spill and fire. Do NOT walk away, stand by w/ switch and fire extinguisher
__________________
(TerryH.) 2000-GS Conquest Limited 6266 Class-C 99-E450SD V10
THenne1713 is offline   Reply With Quote
Old 09-03-2018, 07:24 AM   #11
Senior Member
 
Arby49's Avatar
 
Join Date: Jul 2016
Posts: 617
Just saw this post, but wanted to throw something in the mix. We were experiencing the same sort of problem until it finally quit running altogether. Had the brushes replaced in the motor, everything has been fine since.
__________________
Russ & Lois Bell
2008 Monaco Dynasty Yorkshire IV
2013 Ford Flex
Arby49 is offline   Reply With Quote
Old 09-03-2018, 07:26 AM   #12
Senior Member
 
BrokeDown's Avatar
 
Join Date: Mar 2016
Location: Fort Myers, FL
Posts: 604
Quote:
Originally Posted by THenne1713 View Post
Just be careful bypassing the CB/ relay, because if it continues to run w/ gen shut down, it can overpower the float needle and could cause a flooded engine, and/ or worse, fuel spill and fire. Do NOT walk away, stand by w/ switch and fire extinguisher

This is a diesel generator so no carb/float.



I believe the fuel pump circulates fuel through the fuel system. From the fuel tank, there are two hoses, one supply and one return.


In any case, I will be sure to shut down the fuel when I stop the generator.


Thanks.
-B
__________________
Full time RVer since 4/2016. Newmar Mountain Aire 4523 - Jeep Rubicon - Harley FLTCR - 2022 F450 Platinum, 2022 Momentum 351MS-R with Curt Flex Air hitch and MORryde IS - Also considering a Polaris General 4 Seater and a Can Am Spyder RT
BrokeDown is offline   Reply With Quote
Old 09-03-2018, 07:33 AM   #13
Senior Member
 
BrokeDown's Avatar
 
Join Date: Mar 2016
Location: Fort Myers, FL
Posts: 604
Quote:
Originally Posted by Arby49 View Post
Just saw this post, but wanted to throw something in the mix. We were experiencing the same sort of problem until it finally quit running altogether. Had the brushes replaced in the motor, everything has been fine since.

Russ,
Were you getting a code with your shut down? I am getting a 3-6.



I think I read your post somewhere along the way, you had 3,000+ hours on your unit? I have under 1,500.


The Onan Tech told me that there is a quick check for the brushes. He said you check the lead to the brushes. If they are slack, the brushes are not wore out. I will do that check if the bypass wire does not fix the problem.


-B
__________________
Full time RVer since 4/2016. Newmar Mountain Aire 4523 - Jeep Rubicon - Harley FLTCR - 2022 F450 Platinum, 2022 Momentum 351MS-R with Curt Flex Air hitch and MORryde IS - Also considering a Polaris General 4 Seater and a Can Am Spyder RT
BrokeDown is offline   Reply With Quote
Old 09-03-2018, 07:38 AM   #14
Senior Member
 
Arby49's Avatar
 
Join Date: Jul 2016
Posts: 617
Quote:
Originally Posted by BrokeDown View Post
Russ,
Were you getting a code with your shut down? I am getting a 3-6.



I think I read your post somewhere along the way, you had 3,000+ hours on your unit? I have under 1,500.


The Onan Tech told me that there is a quick check for the brushes. He said you check the lead to the brushes. If they are slack, the brushes are not wore out. I will do that check if the bypass wire does not fix the problem.


-B
I was getting a code, which I think was 3-3? At last check, the hours were at 1800. Hope this helps. The tech came to my location and had it repaired in a couple of hours. Total cost was $180.00.
__________________
Russ & Lois Bell
2008 Monaco Dynasty Yorkshire IV
2013 Ford Flex
Arby49 is offline   Reply With Quote
Reply

Tags
fuel, fuel pump, onan, wiring



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 10K Fuel Filter Replacment Hours lwmcguire Class A Motorhome Discussions 6 08-08-2018 09:46 AM
Onan 10k fuel filter replacement cruzbill RV Systems & Appliances 36 03-09-2018 09:13 AM
10k and 12.5k Onan gen. fuel filter tom chelbana RV Systems & Appliances 5 07-23-2016 06:18 PM
Onan 10K Won't Stay Running Doc Mark Newmar Owner's Forum 4 09-30-2011 09:31 AM
Onan 10K Diesel Generator al_mers MH-General Discussions & Problems 7 02-26-2010 10:49 AM

» Featured Campgrounds

Reviews provided by


All times are GMT -6. The time now is 03:04 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.