Ford F-700 Brakes Locked
04-28-2005, 08:04 AM
#1
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Ford F-700 Brakes Locked
Morning,
This is not diesel related, but I figure you guys know alot more about this stuff than me. I own a Ford F-700 with a 370 4v motor. It has an electric brake motor that I suppose helps the hydraulics. Anyway the parking brake is just a push button that actuates a solenoid on in the engine compartment to lock the brakes. The truck is dead and wont start and I tried to pull it with my CTD and can't move it. Is there a way to unlock those brakes, or am I dead. Thanks for any help.
Cole
This is not diesel related, but I figure you guys know alot more about this stuff than me. I own a Ford F-700 with a 370 4v motor. It has an electric brake motor that I suppose helps the hydraulics. Anyway the parking brake is just a push button that actuates a solenoid on in the engine compartment to lock the brakes. The truck is dead and wont start and I tried to pull it with my CTD and can't move it. Is there a way to unlock those brakes, or am I dead. Thanks for any help.
Cole
04-28-2005, 08:14 AM
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A couple of things. Check to see if you have power in and out of the switch. Some systems are set up to lock the brakes in the neutral position then when power is supplied, the brakes unlock. Do you have power into or out of the solenoid? You can run a wire from 12V+ to the 'brake' side of the solenoid, this should unlock them.
04-28-2005, 10:50 PM
#3
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go to the rear brakes and tighten the nuts on the adjusters on the "cans" be sure to chock the wheels first!!! the brakes will not unlock without running the engine but you can pull the adjusters to release them.
04-29-2005, 12:40 AM
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Sounds like you have the lucas girling brake system. I HATE THOSE SYSTEMS!!!!!! They are expensive to rebuild and a major PIA to work on. When you turn on the key with the eng off, an electric pump is supposed to turn on to build up pressure to power the brakes. I think there is a solinoid that turns on the power to the electric pump. Make sure the battery is up first. I haven't worked on one of those in several years, and I do not miss them!!! Good luck
04-29-2005, 03:28 AM
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Disconnect the dead battery, install a good battery, press the brakes until you hear the electric booster kick in, then hit the parking brake lock switch while the electric motor is running. The system will unlock.
What you have is a Dayton system manufactured for Oshkosh, Ford, and Freightliner. You have to have power and the system has to develop enough pressure to allow the solenoid to release. The electric motor is a back-up to the hydraulic lines you will also find running to the brake booster system from the engine power steering pump.
Once it is released, the rig will roll right along.
What you have is a Dayton system manufactured for Oshkosh, Ford, and Freightliner. You have to have power and the system has to develop enough pressure to allow the solenoid to release. The electric motor is a back-up to the hydraulic lines you will also find running to the brake booster system from the engine power steering pump.
Once it is released, the rig will roll right along.
05-03-2005, 07:39 AM
#6
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Thanks a bunch guys. When I turn the key to on, the brake motor runs and there is a light on the dash that says Elec Brake Motor on. I just got back to town and will mess with it today. The starter was bad and my guys killed the battery trying to start it so I couldnt unlock the brakes. Hopefully we'll get her running today
Thanks
Cole
Thanks
Cole
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