Leaking Manifold 8.3 Cummins

[Coma]

Originally Posted by walt2137

This is a past from another Forum, this homemade penetrant really works, I have used it on rusty tractor equipment and many other jobs also on manifold bolts, it does the job.

April 2007 "Machinist's Workshop" magazine comparison test. They arranged a subjective test of all the popular penetrants with the control being the torque required to remove the nut from a "scientifically rusted" environment. Penetrating oil ......... Average load None ..................... 516 pounds, WD-40 .................... 238 pounds, PB Blaster ............... 214 pounds, Liquid Wrench ............ 127 pounds , Kano Kroil ............... 106 pounds , ATF-Acetone mix............ 53 pounds The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic transmission fluid and acetone. Note the "home brew" was better than any commercial product

I used this before I took mine in for manifold replacement. MH was 14 YO. Not a single broken bolt.

[sjholt]

""Whenever you apply the PAC brake, it generates an immense amount of heat in the exhaust manifold because of exhaust gases being trapped by the butterfly flapper in the exhaust brake. I now us more discipline in how long I leave the PAC brake engaged during deceleration and use a little more of a combination of wheel brakes and exhaust brakes""


Not so. If you had a pyrometer you would see the temps go down rather fast.

[dieselbeaver]

The slip joint is leaking... It is a machined slip fit when new, but it can wear out over time. Applying a never seize to it when new may help prolong its life.

The only thing I know of to due now involves taking it back off and getting some "exhaust cement" that I know CAT sells for a pretty penny. You follow the instructions and apply it and reassemble everything and let it cute. At that point of all the labor and hassle I might think of just replacing it.

They aren't the heaviest castings to begin with and they have a tendency to warp as it is. With all the coaches out in the market I'm kinda surprised a performance manifold like what is offered for the 5.9's hasn't come out.

That's all I got,
Allen