I have a new to me 1988 LX 5.0 with a brake issue. I don't know much about the car itself and its my first dive into a fox body. I've had a 66 Mustang for 30 years so I know enough to be dangerous. The LX has had a 5 lug swap with cobra brake calipers. The brake pedal goes to the floor and there is about ZERO brake response. The engine is supercharged, and it idles at around 7 inches of mercury. I'm guessing that's not enough to supply the booster properly. However, if I understand how the booster works, low vacuum pressure would not equate to a pedal that pushes to the floor. If the car was only low on vacuum then the pedal would be hard to press, not easy, correct? While I may indeed have a booster issue with low vacuum my guess is I first have some hydraulic issue with brake lines or the master cylinder. Without the car running or any mechanical advantage I should be able to get a firm pedal if everything on the hydraulic side of the system is working the way it should. For my low vacuum pressure my thought is to add an electric vacuum pump but I'm open to ideas on that. Someone please point me in a direction. Thanks.
Brakes 88 LX 5.0 - help! no brakes
- Thread starter DRGunn427
- Start date
I don't know much about the effects of boost and low vacuum issues with brake boosters but yes you have a hydraulic pressure issue or rather a lack of hydraulic pressure, start with fluid in the master cylinder, if it's dry you may have to bench bleed it.
You also need to ID the brake booster, stock fox booster or a cobra style, a pic may help.
You also need to ID the brake booster, stock fox booster or a cobra style, a pic may help.
You either have air in your system or a MC going bad........
Your brake system is not stock so make sure all of the caliper bleed screws are at the top of the caliper... Seen calipers installed wrong before..
Your brake system is not stock so make sure all of the caliper bleed screws are at the top of the caliper... Seen calipers installed wrong before..
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When the engine is not running what does the pedal feel like? Is there brake fluid in the MC reservoir? Have you bled the brakes? I have more questions but need these answered to ask the right ones.
Since its new to you and there are no brakes , its time to get her ass on four jack stands( or a lift ) and go over the entire brake system.
Last thing you need is a wreak.
There is great info on the cobra brake swap on here, read all of it twice to start with.
Take pics and post them up .
Last thing you need is a wreak.
There is great info on the cobra brake swap on here, read all of it twice to start with.
Take pics and post them up .
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