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Topic: Turbo boost pressure (Read 349 times) previous topic - next topic

Turbo boost pressure

My coach has been consistently producing 23psi max at 100% load. This cummins ISL400 seems to have less pep than the same engine I had in our 2006 Nimbus. Unfortunately I have no memory of the boost in that coach. I believe I saw another comment on the forum that stated he was informed he should be getting 31psi at max if my poor memory is correct. I have had no problems on the hills going and returning from NAC to Alabama a week ago but the performance is less than expected.
The CAC looks to have been recently worked on or replaced as it is bright silver compared to everything else.
Any thoughts?
Thanks as always...
Tyson
Tyson
2004 295 3610 WTFS
2010 Honda CR-V
Motorcade #18344
AA1DS

Re: Turbo boost pressure

Reply #1 –
With boost being the issue I would first check the rubber boots and clamps on the piping from the CAC to the engine. Feel all over the boots for hole or tear and check the clamps for tightness.
Dub McBride 1996 270

Re: Turbo boost pressure

Reply #2 –
Tyson,

You can call Cummins with your engine serial number to verify what boost should be. Cummins 800-286-6467

On most engines, if fuel flow is restricted, the ECM also restricts boost.

So, probably a good idea to change fuel filters-- an inexpensive first step along with visually checking for leaks from turbo through CAC back to intake manifold.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Turbo boost pressure

Reply #3 –
Good info guys, thanks will do...
Tyson
Tyson
2004 295 3610 WTFS
2010 Honda CR-V
Motorcade #18344
AA1DS

Re: Turbo boost pressure

Reply #4 –
On those large hose clamps is there a torque number? With the spring associated with the nut do you just snug it up to let the spring keep tension or should it be tightened fully?
Thankfully there are no dumb questions....
Thanks,
Tyson
Tyson
2004 295 3610 WTFS
2010 Honda CR-V
Motorcade #18344
AA1DS

Re: Turbo boost pressure

Reply #5 –
Quote from: Frontier Camping –
On those large hose clamps is there a torque number? With the spring associated with the nut do you just snug it up to let the spring keep tension or should it be tightened fully?
Thankfully there are no dumb questions....
Thanks,
Tyson

 I don't know the specific answer as to torque, but I can say with authority that if the piping separates it WILL melt air lines with very BAD results.
In restless dreams I walked alone.
Narrow streets of cobblestone.


'93 U225
Build 4337
'14 CRV Toad

Re: Turbo boost pressure

Reply #6 –
I've just always tightened the clamps by feel and on the tight side.I've had clamps break over time but not get loose. I've had the rubber boot split and it's an easy fix. Always good to carry spare clamps and boots in parts bin. I hope your issue is this simple. I like to use a ratchet and socket on the clamps.
Dub McBride 1996 270