Charge Air Cooler Leakdown Check

[Birddog Pilot]

I can't find my notes on the test parameters for the charge air cooler leakdown test, does anyone have the information? It's something like: Plug the ports, attach gauge, apply 10 psi (or some pressure?), and see what the leakage is after so many seconds.
Thanks,

[shiggs68]

If you are referring to air conditioning, you draw down a vacuum. Close the ports and let it sit 20 to 30 minuets. Then check with the manifold gauge for any change. This serves two purposes, checking for a leak and boiling out any moisture which is caustic when mixed with the charge freon.


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[wolfe10]

The CAC (Charge Air Cooler) works with boost pressure. So around 25 psi= 50 Column Inches HG.

No sure I have ever seen any leak down specs, but you want close to 0 leakage.

Said another way, any leakage reduces boost PSI to the engine.

Brett
2003 38 FDDS

[Old Scout]

Don't recall whether any specs were given but do seem to remember an owner who was trying to test their CAC but was having trouble creating enough pressurized air volume to accomplish the test. Suspect even a Cummins shop has to contract out to a radiator company. Again, as I recall, the thread suggested a turbo has a lot of capacity to overcome modest leaks in the system. So a CAC could have a fairly significant "leak" and still pass a test. I had a CAC failure that involved a ruptured cross tube--not repairable. Simple gasket leak[s] between tanks and coil--try to tighten bolts or replace gaskets.

[DrDaveMA]

Bird dog, I think the significant question here is, why do you want a leakdown spec, are you having problems, if so tell us what is wrong, or do you just want the spec?

[Birddog Pilot]

Thanks all, yes, the leakdown check that I am referring to was once upon a time quoted to me by a Cummins facility but I just can't recall the specific details.
We are here at Mac's Radiators in Portland, OR having the coolant radiator either rebuilt or replaced, and in addition the CAC is also leaking. The CAC was repaired by Cummins in San Diego about four years ago but appears it may have only been disassembled, inspected, and put back together again. New gaskets or just retorqued, who knows? Mac's and I are currently researching if Radiator Specialities made the CAC and if a repair kit is available. Anyone else had any experience with this item? If a new CC is required, unfortunately Dura-Lite is no longer an option, apparently they no longer offer a unit for Alpines; that would only leave Radiator Specialities in Sacramento.

[Phil R]

Maybe this will help. Is there a testing guideline to follow to determine if a Charge Air Cooler is leaking out of specification? | Dura-Liteâ„¢

[Dr4Film]

My CAC was tested while submerged in a huge water tub with one opening plugged and the other opening had a plug with an air hose connection. They showed me how bad it was leaking.

This was at the Bryce-Thomas / CG&J Radiator Shop in Gadsden AL where I was having my new radiator built and installed.

The CAC was attached to the radiator and both had to come out or the radiator replacement. It was a good time to rebuild the CAC too.

Dr4Film ----- Richard

[Birddog Pilot]

Thank you Dr4Film and Phil R, excellent info. Yes, same procedure used with the tank of water and apparently CAC was leaking a bunch, probably vastly exceeding your Dura-Light specs Phil R. Yes, those D-L numbers are pretty much what I recall Cummins mentioning about four years ago.
Presently still researching availability of gasket kit or new CAC. The radiator is ready for install and the money machine counter is madly ticking away.

[JWJ]

Did you find a replacement
I am looking for the same thing.

[Birddog Pilot]

JWJ, Yes, Idid find the replacement, and it was from Radiator Specialties in Sacramentowhich was the OEM for the WRV's complete radiator package. My original p/n wasRS-5002, but that is now superseded with RS-5044; which I am happy to reportfit perfectly. I would have much preferred a Dura-Lite replacement, but as Imentioned previously they have discontinued making a CAC for Alpines. That is really a shame, because their CAC’shave an excellent reputation.

I was quitedisappointed that I couldn’t find any information either from Radiator Specialtiesor their Oregon distributer Source Engineering in Eugene regarding a gasketkit. In 2011 when Mac’s brass/steelcoolant radiator was overhauled in San Diego, the shop also installed newgaskets to repair a leaking CAC. Now, neitherthe manufacturer nor its distributer had any information regarding the availabilityof such a kit. This seems unusual inthat RS was able to manufacture a one-ofCAC, probably utilizing gaskets that I assume might have been suitable for arebuild of the original RS-5002. In anycase the old CAC is in the back of the Jeep and when we get home I’ll see whatI can find in the way of a replacement gasket kit and have it overhauled. We Alpine owners can never have enough sparecomponents.

I might alsoadd, if you have never seen one of these radiator packages during a removal andinstallation process, it is quite educational. The main building point is the coolant radiator which is supported bytwo vibration isolators and two ½” Grade 8 bolts, that’s all that supports the entire package. Thereis a tank welded/soldered/brazed (?) at each end of the core. The aft tank has coolant running through itand the forward tank contains a tube that terminates on the rear of the tank tothe in and out transmission line fittings. Thistube is what keeps our hardworking Allison transmissions happy. With 15+ gallons of coolant that is a lot ofcooling action flowing past the one heat transfer tube. The hydraulic cooling fan and shroud aremounted to the rear, inboard, of the coolant radiator. The CAC is outboard of the coolant radiatorand has the oil cooler mounted beneath. Then the last outboard component is the AC condenser which is also mounted to the CAC. That makes quite a package and a lot ofengineering went into all the brackets and various attach points; it also makesfor a whole lot of weight hanging from these two ½” bolts. Further, in regard to the vibration isolatorsthere are at least two options available from Mission Sales in Texas. Do check out this topic here on the “Forum,” Radiator - Top mounting vibration dampers,items 2, 11, and 13. Terry and Jim have some excellent informationthat should answer most of your questions. With the CAC out of the way, this would be an excellent opportunity to change the isolation dampers.