Author Topic: PAC Brake troubleshooting  (Read 1731 times)

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Offline jplante4

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PAC Brake troubleshooting
« on: September 11, 2018, 03:42:39 PM »
CAT 3126/Allison in a Safari Sahara coach. PAC Brake has never worked near as I can tell. I thought everything was great, but I was just sensing the downshift (first diesel coach).

Took the brake apart and freed up and lube all lube points. Got a new quick release valve and associated fittings. Piston works great when not installed on the butterfly using 85 lbs of air from a compressor. I suspected the PAC compressor, but the air horns work fine and there is pressure in the system. I bought a spare compressor anyway. The butterfly valve moves freely, everything is lubed and I can't see anything binding. When I put the piston on the butterfly valve and apply air pressure, nothing moves after I tighten the clamp on the butterfly shaft. I can move the valve by hand, but it is stiff.

Is there a way to adjust the spring tension on the butterfly shaft? It's the only thing I can think of that would cause the mechanism to bind.

Offline Brett Wolfe

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Re: PAC Brake troubleshooting
« Reply #1 on: September 15, 2018, 06:51:44 AM »
I have found PacBrake to be pretty good on the phone in diagnosing product problems.

Have you run this by them?

Offline Ken Carpenter

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Re: PAC Brake troubleshooting
« Reply #2 on: September 15, 2018, 07:01:03 AM »
PW brake support number is tel:8006630096
2005 Winnebago Journey 39K, C7 350HP
Jeep Grand Cherokee, Airforce One
Diesel RV Club Officer & Board Member