Go Back   iRV2 Forums > THE OWNER'S CORNER FORUMS > Monaco Owner's Forum
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 04-09-2017, 06:24 AM   #1
Senior Member
noeldale's Avatar
Monaco Owners Club
Holiday Rambler Owners Club
Join Date: Sep 2007
Location: SE MI
Posts: 711
Blog Entries: 15
Vacumn Pump

With just ignition on and vent selection to anything but 'Off', before starting engine I get a weird noise from the engine compartment, DP, that I cannot find. If the vent control is turned 'Off' the noise stops.

I assume it is the vacumn pump for vent controls and is going bad. This does not happen at all times but when it does it is very loud from outside. I've tried touching most of the engine area and cannot find any item with a vibration to know it is working.

Does anyone know where the pump is, what the pump model is, or if this is even the right item to look for?

I've searched for info online but the only conversations are for gas units and they find the pump in the dash area and I know it is not there.

This is in an 03 Neptune 36PBD, 300ISB.

Dale, Mary and Oreo the Malshi, 03 36PBD Monaco Neptune 'The Beast', 06 Malibu Maxx
noeldale 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 04-09-2017, 06:54 AM   #2
Senior Member
onechaddude's Avatar
Join Date: Jul 2011
Posts: 1,587
Sounds to me like it is your vacuum generator you're talking about. My 07 Neptune does the same thing when I turn the key on until it builds vacuum. Then it stops as it should. After about 10 secs it stops regardless of the dash HVAC controls. If you're vacuum generator is making noise it may not be bad. You're problem may be that you have a split in a hose or disconnected hose that's leaking vacuum.

When I bought my coach new in 07 the vacuum generator would run about 10 secs and then be off about 45 secs then on another 10 and so on. I took it back to dealer and they found one hose with a split in it. After replacing it works like it should.

What does yours do after you crank the engine? Does it continually run? Will your dash HVAC switch between defrost and dash and floor?


onechaddude is offline   Reply With Quote
Old 04-09-2017, 06:59 AM   #3
Senior Member
Twomed's Avatar
Monaco Owners Club
Join Date: Oct 2009
Location: On the road
Posts: 1,417
Dorman 904-214 Electric Vacuum Pump Ford Diesel 6C3Z2A451A looks like this on Ebay.

About $50 or you could probably get it from Monaco for around $200
Happy Trails,
06 Dynasty Countess III ISL//3060
07 Hummer H3// Suzi 650 Thumper
Twomed is offline   Reply With Quote
Old 04-09-2017, 08:28 AM   #4
Senior Member
jacwjames's Avatar
Monaco Owners Club
Join Date: Jun 2014
Posts: 4,742
My vaccum pump is located under a black metal box.

I had a problem a while back with mine. I had installed a Onan Auto Generator start on the firewall. While doing this I hit one of the vacuum lines causing the pump to click continuously. The controls still worked but I had a leak. Finally traced it down to a loose hose.
Jim J
2002 Monaco Windsor 38 PKD
2005 Jeep Grand Cherokee w/5.7 Hemi
jacwjames is offline   Reply With Quote
Old 04-09-2017, 11:16 AM   #5
Senior Member
noeldale's Avatar
Monaco Owners Club
Holiday Rambler Owners Club
Join Date: Sep 2007
Location: SE MI
Posts: 711
Blog Entries: 15
I'll check tonight on the leak situation and get around to hear what is going on.

The dash controls do work and it will switch from on setting to another.

I'll also see if it goes off after the engine is running.

Thanks for the suggestions and possible part. That will help me find it and see if there is a hose off.

More later after I check.
Dale, Mary and Oreo the Malshi, 03 36PBD Monaco Neptune 'The Beast', 06 Malibu Maxx
noeldale 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
Vacumn Acellerator on 1989 Country Coach joecpayne Class A Motorhome Discussions 0 05-10-2013 05:27 PM
central vacumn vscoggin Class A Motorhome Discussions 12 04-17-2013 09:47 PM
Vacumn hookup Doc S Entegra Owner's Forum 2 08-18-2012 06:27 PM
Vacumn nipple on 8.1 Oklahoma MR C Workhorse and Chevrolet Chassis Motorhome Forum 4 09-09-2008 09:10 AM
toad brake with vacumn sal avitabile Toads and Motorhome Related Towing 5 11-29-2005 05:23 AM

» Virginia Campgrounds

Reviews provided by

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 12:31 AM.

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