Free 7 Day Trial RV GPS App RV Trip Planner Campground Reviews RV Maintenance Free 7 Day Trial ×
RV Trip Planning Discussions

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.
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 02-10-2021, 09:56 PM   #1
Member
 
00zx6r's Avatar
 
Join Date: Aug 2020
Posts: 48
1999 Cummins ISM turbo boost psi???

Does anyone know the normal turbo boost range? I purchased 1999 H/R Navigator 70k miles Cummins ISM no EGR. I put in few thousand miles since purchased and have never seen the turbo boost passed 15 PSI. No codes, new air filter, new fuel filters, new coolant and trans coolant. The local shop checked found no leak in the CAC and proposed to replaced the turbo. Brand new turbo installed and the turbo boost still not passed 15psi.
I am towing 7k lbs trailer no problem on the flat but 35-40 mph up 6% hill, is this normal? This is my first diesel pusher, I used to own class C E450 for 15 years with same trailer weight and can do 6% hill in 45 mph. Also the diesel pusher has 4:30 in gear ratio.
Thanks!
__________________
1999 H/R Navigator ISM
Toad 2002 Tundra Mid Travel
00zx6r 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 02-11-2021, 07:09 AM   #2
Senior Member
 
Monaco Owners Club
Join Date: Sep 2014
Posts: 4,256
Not the same but I have a 400 ISL and I've only seen 23 boost.
I know with mine I have to manually down shift to get the rpm around 1900 or so for going up inclines. It's funny but my "cruise" is better at driving this thing than I am so far.
I have figured out that I can't just push the pedal. There's more to it or so it would seem.
I don't think I've really gone up a mountain yet though.
__________________
1996 Tioga Class C
2007 Monaco Diplomat 40 PDQ
TOAD 2012 Cadillac SRX 4
okcnewbie is offline   Reply With Quote
Old 02-11-2021, 07:11 AM   #3
Senior Member
 
Join Date: Oct 2014
Posts: 3,592
Call Cummins with your engine serial number to find out what boost PSI should be. If more than a few PSI lower, start looking for a leak in hoses or CAC.


Cummins 800-286-6467
__________________
Brett Wolfe
Ex: 2003 Alpine 38FDDS. Ex: 1997 Safari Sahara. Ex: 1993 Foretravel U240
wolfe10 is offline   Reply With Quote
Old 02-11-2021, 12:04 PM   #4
Senior Member
 
bigjon42's Avatar
 
Monaco Owners Club
Join Date: Feb 2017
Posts: 176
I have a 99 monaco exec, ISM 450, and consistently get 30lbs boost pulling grades. Your boost is too low, could be fuel filter issue. I have seen this problem from others with pluged fuel filters. Good luck !
__________________
Bigjon & Sandi
99 Monaco Executive M-450
1999 Lexus RX300
bigjon42 is offline   Reply With Quote
Old 02-11-2021, 12:57 PM   #5
Senior Member
 
Outbound's Avatar
 
Join Date: Jun 2012
Location: NorCal
Posts: 2,885
My 500 ISM gets about 25 lbs max, thats 6% grade pulling car trailer.
__________________
Outbound
2002 Monaco Executive 500 ISM
2004 GMC 2500HD 4X4
Outbound is offline   Reply With Quote
Old 02-11-2021, 06:40 PM   #6
Senior Member
 
Kurt Averill's Avatar
 
Join Date: Oct 2013
Posts: 227
My M11 450 gets to 28-30 depending on temp / altitude etc. after rebuilding the turbo and having the CAC re-cored. before the re-core got about 24 max. pulling a little over 10k in enclosed trailer....
Using a Silverleaf VMSPC - but the boost gauge agrees - the boost gauge is a manual gauge so you want to be sure the tubing is good no kinks or holes etc.
__________________
99 Executive 38 - no slides
M11 450 pulling a 28' race car trailer
Kurt Averill is offline   Reply With Quote
Old 02-11-2021, 07:22 PM   #7
Senior Member
 
Join Date: Sep 2020
Posts: 103
It could be that POS gauge on the dash that I wouldnt trust at all (along with the temp gauge and oil pressure). My 01 ism500 showed 38psi when I first bought it but when I put an autometer gauge on it the real boost was 28-29psi which was also verified by the obd2 monitor that I have.
__________________
01 Monaco Executive 43DS
Tuned and upgraded 500hp ISM
DieselDisco is offline   Reply With Quote
Old 02-11-2021, 07:33 PM   #8
Senior Member
 
jcussen's Avatar
 
Join Date: Jul 2018
Posts: 2,813
Had a 99 ISM 450 and also saw about 28-30 pounds of boost.
__________________
Foretravel tag axle 40 ft. 500 hp/1550 ft/lbs ism 1455 watts on the roof. 600 a/h's lithium down below.
jcussen is offline   Reply With Quote
Old 02-13-2021, 10:57 AM   #9
Junior Member
 
Join Date: Jan 2021
Posts: 23
Work the waste gate back and forth and see if it moves freely. It could be staying open a little causing the boost to excape out of the exhaust passage on the housing. I just went through all that. Mine was stuck shut and the pressure from the turbo not being directed out of the exhaust when letting off the throttle was being stopped in the CAC. (dead head pressure) It can only take so many hits and mine blew the top seam out of the CAC. This is bad! but after removing it from the R/V it got worse. The Hot air coming from blown seam on the CAC had made a hot spot on the radiator and it looked like it was gonna leak soon. So this little cast-iron valve can be VERY costly. I purchased mine from a deadbeat seller that knew this was a problem and wouldn't help with the repairs. But its mine and I had to find the problem and fix it correctly. I was getting $15k to 20k quotes. Make this part of your regular maintenance and work the valve several times and keep it oiled.
TFarmer is offline   Reply With Quote
Old 02-28-2021, 12:59 PM   #10
Member
 
00zx6r's Avatar
 
Join Date: Aug 2020
Posts: 48
Update,
Contacted Cummins, provide the ESN but tech was not able to give the average turbo boost psi.
Dropped off the motorhome to friend of friend to get more help on the CAC could be leaking, after looked into it he found no leaking, bottom line is the turbo boost still low (less than 15 psi) and I am still feeling lost the power.
Next step, I will try to replace the turbo boost sensor.
__________________
1999 H/R Navigator ISM
Toad 2002 Tundra Mid Travel
00zx6r is offline   Reply With Quote
Old 02-28-2021, 04:25 PM   #11
Senior Member
 
Join Date: Jul 2014
Posts: 28,610
Have you checked the fuel line for a inline filter hidden along the chassis rail ?

Its more like a strainer but over time it does get plugged up.

No fuel, no boost.
twinboat is offline   Reply With Quote
Old 02-28-2021, 06:23 PM   #12
Junior Member
 
Join Date: Dec 2020
Posts: 15
Quote:
Originally Posted by bigjon42 View Post
I have a 99 monaco exec, ISM 450, and consistently get 30lbs boost pulling grades. Your boost is too low, could be fuel filter issue. I have seen this problem from others with pluged fuel filters. Good luck !
Same with mine...highest I've seen was 32 psi on the gauge and the road tec
__________________
99 Monaco Executive 450 M11
Fu227 is offline   Reply With Quote
Old 02-28-2021, 07:00 PM   #13
Senior Member
 
Join Date: Jul 2014
Posts: 28,610
I just stole this picture from another post .

It shows the strainer I mentioned connected to the copper lines.

You may not have one but its worth a look.Click image for larger version

Name:	Capture%2B_2021-02-28-20-57-53.jpeg
Views:	28
Size:	44.3 KB
ID:	319671
twinboat is offline   Reply With Quote
Old 03-01-2021, 09:02 AM   #14
Member
 
00zx6r's Avatar
 
Join Date: Aug 2020
Posts: 48
Quote:
Originally Posted by twinboat View Post
I just stole this picture from another post .

It shows the strainer I mentioned connected to the copper lines.

You may not have one but its worth a look.Attachment 319671
Thanks twinboat - I will check it on my motorhome.
__________________
1999 H/R Navigator ISM
Toad 2002 Tundra Mid Travel
00zx6r is offline   Reply With Quote
Reply

Tags
1999, cummins, turbo



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
1999 8.3L Cummins temp turbo boost loss jwinston Cummins Engines 8 11-07-2017 06:00 PM
Cummins ISM engine versus Cummins Non ISM engine gimlimike Newmar Owner's Forum 4 08-06-2017 04:39 AM
Turbo Boost What is the Maximum Boost that a 5.9, 275HP shogun1940 Cummins Engines 10 11-30-2014 07:47 PM
ISM went limp, no turbo boost Genset Cummins Engines 1 09-26-2013 08:34 AM
Monaco Dynasty 09' ISM 500 Turbo boost pressure twincessna Monaco Owner's Forum 2 05-03-2012 11:18 AM

» Featured Campgrounds

Reviews provided by


All times are GMT -6. The time now is 04:32 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2021, vBulletin Solutions, Inc.