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Testing CAC

I pressure tested my Charge Air Cooler today. Kinda followed John and Chris's method. I gotta say this would be a lot easier with the CAC out of the vehicle. Anyhow, I used a piece of wood with rubber backing with a male air connection held tight to the CAC with a pipe clamp. On the other side I used the stock hose piece with a can stuffed in it. Held 45 psi with no leaks. Check out the third photo of the can. I'm thinkin' another 5 psi would have blown the back off of it! My advice to others that want to check your CAC; let someone else do it!
jor

Re: Testing CAC

Reply #1 –
Jor --Glad you were BRAVE!!!
Chris
1999 U 320 DGFE
Build Number 5523
Chris & Elka Lang
In the field, Lonoke AR

Re: Testing CAC

Reply #2 –
Well done John see how easy it is to check pressure.
I did mine with it out due to repair of holes in cooling fins
JohnH
Coachless, now use aircraft.
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Testing CAC

Reply #3 –
I would not run the pressure up more than peak turbo boost pressure plus 10%, and then time the leak down. My best guess is they all leak a little.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: Testing CAC

Reply #4 –
We use capped pvc with a valve stem fitted in one end.
Dub McBride 1996 270

Re: Testing CAC

Reply #5 –
Think when they did mine they went to 50lbs,Phred,it's a metal vessel why would it always have a leak?
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Testing CAC

Reply #6 –
Quote from: jor –
I'm thinkin' another 5 psi would have blown the back off of it! My advice to others that want to check your CAC; let someone else do it!
jor

About 600 lbs of force pushin on that can, come to think of it a selenoid valve, tee, potato and trigger and tailgaters would no longer be an issue.
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Testing CAC

Reply #7 –
Why do this test ?  What indication is there that may be reason to suspect a leak ?  I may have a problem and am not smart enough to know it.  Have a great day  ----  Fritz
Fritz & Kathy Johnson
1991 36'

Re: Testing CAC

Reply #8 –
Quote
potato and trigger and tailgaters would no longer be an issue.
Reminds me of the potato bazooka guns one of my kids used to make. Lots of fun blasting those babies into a brick wall.

Quote
Why do this test ?
I guess if you were getting insufficient boost it would be a good idea. I just wanted to do it for fun.
jor

Re: Testing CAC

Reply #9 –
With no boost gauge, in many cases it is difficult to tell you have a problem until significant loss of power.  Don't know that I would do this as Preventive Maintenance, but if power issue or you are already under there working in the area, not a bad idea.

BUT (large BUT), as others have suggested, the force of 30 PSI on  those end caps is significant.  Do not be in the "line of fire" when pressurizing!
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: Testing CAC

Reply #10 –
Visibly  check it first and is the boost power will not get up to specs you may have a leaking CAC. I had 4 good sized bolt holes from a loose fuel cooler rattling it for years before I bought it.  Massive difference after my fix. With the  help from my Banks I get 32lbs which is great.
JohnH
Coachless, now use aircraft.
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Testing CAC

Reply #11 –
I only put about 15 lb of pressure on mine had a gauge in line and once air was off just watched gauge drop then started looking for holes. I'm hard hearing so listening for air leaks don't work.
Chris
1999 U 320 DGFE
Build Number 5523
Chris & Elka Lang
In the field, Lonoke AR

Re: Testing CAC

Reply #12 –
Regarding CAC, I've heard mention of the desirability of adding a second cooler in series with the first.  This seems doable though it would take some piping.  What would be the advantage of adding a CAC?  Would it, in conjunction with some increased fueling make a safe power upgrade path?  Would it support a larger turbo?

Wouldn't mind  a power bump  on my 300 Cummins 8.3.
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Testing CAC

Reply #13 –
Chuck,

Not too difficult to do a TEST to see if your current CAC is adequate or if "more is better".

And, on newer/electronic engines, this data is available on Silverleaf, Scangauge D, etc

Need a temperature probe somewhere between CAC exit and engine intake manifold or intake manifold itself.  The newer engines tell you intake manifold temperature.

If within 10-15 degrees of ambient temperature, your CAC is doing what it should and extra cooling will likely do very little good.

If big delta between ambient and intake, start by really cleaning the CAC and radiator.  Simple Green EXTREME is aluminum-friendly and works well.

If still a big delta, look at condition of CAC and/or supplemental CAC.  I really doubt you will need to go to this step unless the CAC is bad.  Said another way, suspect the CAC was properly speced.
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: Testing CAC

Reply #14 –
Thank you Brett.  Sometimes I tend to overlook the basic first steps and this is good information.
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Testing CAC

Reply #15 –
Not knowing what is normal is a problem.  My m11 shows in the upper 20's at full revs up a grade. 27 or so 28 once.  Is that good?
"Riding and rejoicing"
Bob & Susan
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Testing CAC

Reply #16 –
Call Cummins with your engine serial number.  They should be able to look up max boost for your engine.

Cummins 800-286-6467
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: Testing CAC

Reply #17 –
My cummins guy said 15 to 20 pounds under max load for a M-11
Chris
1999 U 320 DGFE
Build Number 5523
Chris & Elka Lang
In the field, Lonoke AR

Re: Testing CAC

Reply #18 –
No, 27-29 are good numbers for an M-11.  15 to 20 is way low.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R