RV Trip Planning Discussions

Go Back   iRV2 Forums > POWER TRAIN GARAGE FORUMS > Cummins Engines
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
 
Thread Tools Search this Thread Display Modes
 
Old 09-21-2019, 04:40 PM   #1
Senior Member
 
Joe II's Avatar
 
Join Date: Jun 2010
Location: Cedar Rapids, Iowa
Posts: 148
Overpressure?

I have an ISL 8.9L in my freightliner m2. Under hard acceleration it sounds like air escaping. When I let off the throttle it goes away, if I donít push too hard it doesnít happen. Just curious if itís normal.
__________________

Joe II 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 09-21-2019, 04:46 PM   #2
Senior Member
 
Join Date: Nov 2015
Posts: 10,639
NO it is NOT normal


You have an 'air charger' hose leaking
Tubo spins up due to increase in exhaust pressure
It supplies combustion air -----pressurizes the air charge hose then thru the air charge cooler then to intake manifold


Need to check hose, hose clamps, air charger cooler heads, intake manifold for LEAKAGE
__________________

__________________
Is it time for YOUR Medication or Mine?
Dodge 3500 w/Tractor Motor & NUWA 5vr
US NAVY---USS Decatur DDG-31
Old-Biscuit is offline   Reply With Quote
Old 09-21-2019, 04:48 PM   #3
Senior Member
 
Join Date: Jan 2018
Posts: 1,314
You have a boost leak. Get it attended too because sometimes air leaks out, other conditions dirt is leaking in.
__________________
Been through all the continental states and provinces. Loving life on the road.
Finance is offline   Reply With Quote
Old 09-21-2019, 04:53 PM   #4
Senior Member
 
Joe II's Avatar
 
Join Date: Jun 2010
Location: Cedar Rapids, Iowa
Posts: 148
Wow. I guess I have some work to do.
Joe II is offline   Reply With Quote
Old 09-21-2019, 05:23 PM   #5
Senior Member
 
Join Date: Jul 2014
Posts: 19,080
The turbo charger hoses are about 3" in diameter.

Look for the shinny pipes with short hoses on them, connecting to a radatior looking thing, sandwiched with the coolant radatior.

Many times one of the hose's rip open.
twinboat is online now   Reply With Quote
Old 09-21-2019, 05:38 PM   #6
Senior Member
 
Joe II's Avatar
 
Join Date: Jun 2010
Location: Cedar Rapids, Iowa
Posts: 148
Ok. Itís done it since new, I thought it was an overpressure valve or something. Itís got 15k miles now.
Joe II is offline   Reply With Quote
Old 09-21-2019, 07:35 PM   #7
Senior Member
 
A Traveler's Avatar
 
Join Date: Aug 2017
Posts: 676
Overpressure?

My ISL did the same thing and it was a cracked exhaust manifold. This was a common problem on the ISL.

Time for a visit to your nearest Cummins shop. Have them look it over.
A Traveler is offline   Reply With Quote
Old 09-21-2019, 08:09 PM   #8
Senior Member
 
Join Date: Nov 2015
Posts: 10,639
Open Hood..start engine
Go to high idle
Then inspect/listen for LEAKS
__________________
Is it time for YOUR Medication or Mine?
Dodge 3500 w/Tractor Motor & NUWA 5vr
US NAVY---USS Decatur DDG-31
Old-Biscuit is offline   Reply With Quote
Old 09-21-2019, 08:48 PM   #9
Senior Member
 
Joe II's Avatar
 
Join Date: Jun 2010
Location: Cedar Rapids, Iowa
Posts: 148
Thanks. Iíll start inspecting things tomorrow.
Joe II is offline   Reply With Quote
Old 09-22-2019, 01:15 PM   #10
Senior Member
 
Joe II's Avatar
 
Join Date: Jun 2010
Location: Cedar Rapids, Iowa
Posts: 148
I checked all the hose clamps and the rubber hoses. All are good. I set it to high idle and could feel a little bit of air coming out of the union of the turbo and the elbow. I tightened up the clamp but it didnít stop the air so Iíll see if Thereís a gasket that goes between the elbow and the turbo.
Joe II is offline   Reply With Quote
Old 09-22-2019, 06:41 PM   #11
Senior Member
 
Join Date: Feb 2018
Posts: 174
I bought a pvc cap of the appropriate size to fit in one of my rubber hoses by the turbo. I tapped it for 1/4 NPT so I could install a quick connect air hose fitting. I disconnect the charge line from the turbo, install the cap and tighten the clamp to hold it in place. I connect an air compressor to the system and set a regulator to 10-20 psi. It is a lot more convenient (and safer!) to check for leaks when the engine is not running and the engine does not develop much boost pressure at idle to reveal small leaks anyhow. You are likely to find many leaks as I did on mine. Each leak is wasted power!


Good luck!
SlowJoe is offline   Reply With Quote
Old 09-22-2019, 07:21 PM   #12
Senior Member
 
Joe II's Avatar
 
Join Date: Jun 2010
Location: Cedar Rapids, Iowa
Posts: 148
Thanks slow. Iíll do that also.
__________________

Joe II is offline   Reply With Quote
Reply



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


» Featured Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 08:17 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
×