Help with vacuum brake system

Reply Subscribe

Thread Tools

Search this Thread

08-21-2010, 09:21 PM

2010Raptor

New User

Thread Starter

Join Date: Aug 2010

Posts: 2

Likes: 0

Received 0 Likes on 0 Posts

Help with vacuum brake system

I have a 85 F700 with vacuum brakes on the rear. Before we bought it someone had taken all the lines off of the system. So no rear brakes or parking brake. I have the parking brake valve but, could use a diagram to re install the vacuum lines and such to get everything back working. Needless to say... It's a lot of fun trying to stop this beast with just front brakes.
Its a 24ft rollback wrecker. Maybe it is bigger than yours LOL

Reply Like

08-22-2010, 11:22 AM

krewat

Site Administrator

Join Date: Jul 2002

Location: Long Island USA

Posts: 42,561

Likes: 44

Received 298 Likes on 157 Posts

It's going to be fun finding a diagram for this, but maybe someone here can help.

Guys?

Reply Like

08-24-2010, 02:53 AM

Dennis/Ohio

Junior User

Join Date: Feb 2010

Posts: 67

Likes: 0

Received 1 Like on 1 Post

Quote:

Originally Posted by 2010Raptor

I have a 85 F700 with vacuum brakes on the rear. I have the parking brake valve but, could use a diagram to re install the vacuum lines

Parking brake valve? Must be a aftermarket hydraulic parking valve like
this link:
Product Overview and Available Literature | MICO, Inc.
Not safe as the only parking brake.

diagram to reinstall the vacuum lines? Could this have air brakes? I think you should talk to a local medium/heavy duty truck mechanic and get a basic understanding of the brake system you have.

Sorry, I don't have any idea what system you have.

Reply Like

08-24-2010, 10:05 AM

awhtx

Tuned

Join Date: Feb 2006

Location: Lampasas,TX

Posts: 483

Likes: 0

Received 2 Likes on 2 Posts

I think this is what you need.

1985 Ford Medium Heavy Duty Truck Service Manual Set: eBay Motors (item 250678966602 end time Sep-06-10 01:28:26 PDT)

Reply Like

08-26-2010, 07:58 AM

Dennis/Ohio

Junior User

Join Date: Feb 2010

Posts: 67

Likes: 0

Received 1 Like on 1 Post

Quote:

Originally Posted by skyvia

the vacuum brake system is controlled through a brake pipe connecting a brake valve in the driver's cab with braking equipment on every vehicle. The operation of the brake equipment on each vehicle depends on the condition of a vacuum created in the pipe by an ejector or exhauster. The ejector, using steam on a steam locomotive, or an exhauster, using electric power on other types of train, removes atmospheric pressure from the brake pipe to create the vacuum. With a full vacuum, the brake is released. With no vacuum, i.e. normal atmospheric pressure in the brake pipe, the brake is fully applied

Thanks for the info. I thought I could help on this forum with the older trucks but this is the second brake system you guys work on and I've never seen. The first I had never heard of is the Lucas Girling system.
thanks, dennis..

Reply Like