Turbo Exhaust Brake Maintenance Question

[shelland]

I purchased some exhause brake lube from WRV and went under the coach looking for the exhaust brake. I think the exhaust brake is above the turbo and accessible from the bedroom only. Correct me if that is not the case.

I also noticed a small vacuum can with a rod that connected to an arm and shaft that goes through the exhaust just in front of the turbo. This mechanism is located on the exhaust system between the turbo and the engine block. I tried to move the rod but it wouldn't budge so I'm wondering if the shaft is frozen. Should I be able to move the rod and turn the shaft? Is this part of the exhaust brake? I don't think so but I can't see everything from below. Thanks for the help.

[shelland]

I purchased some exhause brake lube from WRV and went under the coach looking for the exhaust brake. I think the exhaust brake is above the turbo and accessible from the bedroom only. Correct me if that is not the case.

I also noticed a small vacuum can with a rod that connected to an arm and shaft that goes through the exhaust just in front of the turbo. This mechanism is located on the exhaust system between the turbo and the engine block. I tried to move the rod but it wouldn't budge so I'm wondering if the shaft is frozen. Should I be able to move the rod and turn the shaft? Is this part of the exhaust brake? I don't think so but I can't see everything from below. Thanks for the help.

[Dave Fernandez]

Hello Steve & Marsha:

The exhaust brake (PacBrake) should be silver in color and has an air line to one end. You can excess through the top of the engine under the bed. You can lube the pins on the exterior and if you remove the air hose you can put a few drops of lube in the opening of the PacBrake. You should not be able to move the PacBrake by hand. During deceleration the airline moves the PacBrake. I can hear mine when if is on as I decelerate and a wall or some thing else is next to me and the sound reverberates back through an open window. When I first heard this I thought something was grinding during deceleration. If you check out the web sit for PacBrake it should be helpful.

You can find a PDF document at the bottom of the page called "Find out how easy it is to operate an exhaust brake. Download an exhaust brake drivers guide."�

[rmmpe]

The other item you mentioned sounds like the Turbocharger's Waste-Gate, which prevents Turbo overspeed. If the exhaust to the Turbo is uncontrolled, a Turbo can generate pressures upward of 2 Atmospheres (30+ psi). Pressures in that range can cause the Turbo to overspeed and disintegrate from centrifugal force and/or cause damage to the After-cooler (Charge Air Cooler) and ducting.

The diaphragm you see is subject to the charge air pressure. When the pressure reaches the proper setting, the diaphragm overcomes the internal spring, extending the rod and opening the Waste-Gate to allow the exhaust gases to bypass the turbo "Hot side".

[shelland]

Thanks for the info. I appreciate it.

[rmmpe]

You're welcome.

[EngineerMike]

The following files will be added to the ACA Tech Library page in a few days. File names are self explanatory, except maybe the "maybe" on the wiring schematic- this is PacBrake's suggested wiring, your WRV MMV.

[Rich and Cork]

Mike, thanks for the bump on this subject. I ordered their lube from Camping World.

[EngineerMike]

I was just reading on another source that one clever owner put in a 12V rocker switch within sight of the PacBrake to be able to cycle the butterfly valve manually while doing the lube or just an inspection. Sounds handy. IIWMI'd consider a relay & in line fuse on the load side of the relay.