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Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3212
Experience:  ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician
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2003 C5500 lost power and blows black smoke, blows

Customer Question

2003 C5500 lost power and blows black smoke, blows intercooler lines off
JA: Have you checked the spark plugs? When was your air filter last changed?
Customer: 6.6 l diesel
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: we removed the exhaust system and looked for restriction
JA: Anything else you think the mechanic should know?
Customer: It will run at an idle but will not run under a load
JA: OK. Got it. I'm sending you to a secure page on JustAnswer so you can place the $5 fully-refundable deposit now. While you're filling out that form, I'll tell the GM Mechanic about your situation and then connect you two.
Submitted: 10 months ago.
Category: Medium and Heavy Trucks
Customer: replied 10 months ago.
Air Filter was changed less than a 1000 miles ago
Expert:  Jeremy replied 10 months ago.

My name is ***** ***** I will assist you with your question today.

I'm an independent contractor and I don't get paid until a rating has been made.

We can go back and forth as needed to help resolve the issue you are having. Follow ups are free after ratings, so rate in confidence!

Which side are you blowing the intercooler lines off? Hot or cold side?

Have you tested the intercooler for blockages? What about the tubes, do they look bent at all? There has been issues with them being bent allowing pressure loss on the system and the lines to blow off.

There is a TSB for it, too.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Oil seepage from turbo charge air cooler hoses, or charge air cooler hose becomes dislodged during acceleration.

It is possible to have DTC P0299.

Due to the closed PCV system on the 6.6 LLY engine it is normal to have oil residue in the air charge cooler hoses and pipes.
The oil will migrate to the lower areas of the air charge cooler system and may cause customer concerns of oil seepage.
This may also cause the Charge Air Cooler hoses to dislodge when turbo boost is high.
Do a visual inspection of Charge Air Cooler connections and hoses.
Replace Charge Air Cooler hoses, pipes, or clamps if damaged.
Properly clean all oil from Charge Air Cooler pipes and hoses.
Charge Air Cooler hoses and pipes are marked for proper installation. The hoses are marked with ENG, DUCT, or CAC (charge air cooler). The hoses and pipes must installed correctly. The engine side is marked ENG, the duct side (the aluminum pipe) is marked DUCT, and the charge air cooler side is marked CAC.
Apply a very thin coat of sealer part number 97720043 to the Charge Air Cooler hose connections.
Install hose and properly torque charge air coolerhose clamps to 70 lb in/8 nm.
Allow the RTV sealer to dry for 3 to 4 hours. Recheck the Charge Air Cooler for leaks using the appropriate Kent Moore leak tester.


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Customer: replied 10 months ago.
The lines are blowing off the hot side
Customer: replied 10 months ago.
We have not tested the intercooler for blockage. What is the best method to use to test that
Expert:  Jeremy replied 10 months ago.

I honestly pull it and send it to a radiator shop for they can dip it and flush it.

Otherwise, pull the cold line off, start the truck and se if you feel pressure coming out. There is a test kit that you can get to test them, but they are expensive. The radiator shop can do it for cheaper than the test kit costs.

You just want to see if there is a good amount of air flow and pressure coming out the cold side. There should be enough there that when the truck is running and you rev it up, you can feel the air coming out 10 feet away at 20 psi. They build to 42 so it should blow very good.

Customer: replied 10 months ago.
The intercooler lines are on the turbo not the radiator
Expert:  Jeremy replied 10 months ago.

The intercooler lines come from the turbo, to the intercooler, then to the intake. I know this.

The radiator shops have test kits for the intercoolers for they are the same material as a radiator, aluminum. That is why I send them to the radiator shop for they can dip them in the solvents that they use which eats the oil out of the inside of the intercooler to keep from having to replace it.

Expert:  Jeremy replied 10 months ago.

I my area, they charge $40 to clean them with the dipping and replacement is $290. That is why I send it to them first when they are plugged and not leaking for they tend to be able to get the plug out which is caused by old, dry oil and dirt from a dusty road.

Expert:  Jeremy replied 10 months ago.

I see you viewed this and this is still showing as an open question due to no positive (3 stars or more) rating.

Were you not pleased with my service to you or is there a rating issue? Please let me know if you still need assistance with this, if there is a rating issue, and/or you need more time to respond.

I like to make sure all my customers are satisfied since you did pay a deposit for me to assist you, whether I’m paid by a positive rating feedback or not.

We can continue where we left off or start over if needed. Also, if you need diagrams, instructions, etc please don’t hesitate to ask.

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