View Full Version : Parking Brake Parts

04-25-2011, 10:16 AM
A couple of questions regarding my Scott parking brakes on a PA-18-150:
1. My right parking brake is behaving differently from the left one. If it is pushed back without applying brake, it remains in that position until the brake is applied. The left one feels like it has a spring inside and always snaps back forward unless it is set with the brake. Aside from that, they both work as expected. Do they have a spring on the inside that might be broken?
2. Are individual parts available for the Scott parking brake? I haven't been able to find anything except the entire unit and I don't want to pull it off until I know.

Thanks in advance.

04-25-2011, 11:19 AM
I think the only individual parts you can get are the 0-rings. There are no springs and they should stay in what ever position you put them in and should release automatically when you apply the brakes.


04-25-2011, 11:56 AM
They are a piston valve. With brakes applied and you pull or push the valve so that it goes in, it stays in because of the back pressure from the valve to the wheel. When you tap depress your brakes -this action pushes the valve back away from the master cylinder (over coming the valve to wheel back pressure) releasing the brake line pressure when it passes and opens the port. No springs, sticky piston maybe.

04-25-2011, 12:46 PM
Ok, great. Thanks. I'm guessing that the left master was serviced well enough that the parking brake lever is moving forward due to a little pressure on the master side (when the brakes are not applied).

Also, the right parking brake is missing the spacer on the shaft between the body and the lever. Is that a critical component? It should be there right?

04-25-2011, 02:40 PM
Are these normally engaged/disengaged with a cable assembly of some sort? I have the parking brakes with just the levers sticking up 90 degrees to the floor. To make a long story short checking them in the off position is now on the landing check list. Anyone have a pic or description of the cable assembly or is exactly what is supposed to be there? Thanks, Jim

04-25-2011, 05:15 PM
They started with a wire (cloths hanger) attached to them that was attached to the seat frame so you could set them from the back seat.