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Leaving substantial oil after idling on 10 hour break

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I have a 2006 CXN with a 460 hp. It had a complete Inframe at the dealer with a new cam a reman head and the other head reworked. Ever since the repair it  will leak oil “sometimes” when the I idle on my 10 hour break. I changed the brake air compressor and the turbo. It still leaks. You can see in the pic it comes out the exhaust manifold, and turbo flange. Took it back to dealer they “ resealed” the lower exhaust studs. They don’t think it’s the rings because the valves aren’t black they looked grayish. Any thoughts? Also it doesn’t pull a hill since the rebuild at all. It actually pulls worse than before the inframe!

E0C1BB10-8A3D-487E-9604-A2E11A8153B6.jpeg

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Looks like unburned fuel slobber coming from exhaust manifold joint. Common with winter cold starts regardless of injector health or idling with bad injectors. Usually leaves two black pus spots on you EUP chrome cover.

Are you adding oil to the engine?

Does your bill include injectors, or did they reuse them?

Slobber coming out of one manifold union joint or both?

what are you boosting at when in a hard pull(PSI)?

Edited by Mack Technician

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We had some guys who were chronic idlers and would idle the truck to cool it before shutting it off at the house. The slobber would climb up the stem of the exhaust valve, he would shut it off, plug it in, go to bed, temps would go sub-zero, slobber turned to adhesive bubble-gum-pus, bond the exhaust valves solidly to the guides and bend his push tubes upon start up cranking.

At the dealership we had a winter law- No shutting off a customers truck (outside) that isn't at full operating temp.   

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I live in the very hot south USA. Heat index averages 98-102 😅. They changed two injector “sleeves”. Not the injectors though. My manifold pressure gauge reads about 25 psi at 70 mph flat ground loaded, it will rise to 35 psi on a big upgrade climb. Before the major engine work I would have a slight trace of slobber near the waste gate. This seems excessive, however I never have to add oil. It is always in range on the dipstick. I truly think it’s internal because of the lack of power on an incline. As for the break in, I had this rebuilt 18 months ago. And I did bobtail(no trailer) about 250 miles home, but it has seen plenty of weight since. 

Edited by Big Red Mack
Adding info

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Test injectors, verify how many bad, replace all if a couple are bad. Also good time to reset overhead on engine, since rebuild, now that your broke in. You have a CCRS engine, they burn through injectors faster than previous vintages. The fuel bangs the tips in multiple hits instead of one burst. 

Unless something has changed.....and Mack shaped up.....??...Locally sourced injector tips were generally better than remack injectors.

Replace all your injector lines, even though they are new, per instruction from Mack. Not sure if you’ve been watching the threads ahead of you.....but folks are still lighting those AC engines up. Your heat index is 98-102 and you engine is capable of taking it to 1,800 if a fuel line fractures. Especially if you sleeping in it, don’t tempt fate, hate to see a brother on the news. 

good luck!🍀 let us know what fixed it.

Edited by Mack Technician

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