Brake pedal stays down.

[triplej1954]

So, I test drove the 98 explorer yesterday. It ran well and has power. Did well for sitting 6 years. But the brake pedal, after you push it down and take your foot off it it does not release, have to pull it up with your foot. I doubt this is a common problem, did not find any threads related to it. Makes for an interesting drive.

 

[XLTrunner]

Do the brakes function normally, otherwise...pulling, dragging, overheating? No loss of fluid? I'd give each wheel a once over to make sure.

I have read of situations where a bad brake booster can cause this. Normally, a defective booster simply causes a hard pedal (much like manual brakes). But, apparently, this is a much lesser known cause of a pedal not returning to normal position. Google it!

 

[Tech By Trade]

Last time that happened to me it was the master cylinder in my 76 chevy. Ended up costing me a deductible. Sucks. Right to the floor in the middle of traffic.

 

[XLTrunner]

I guess I interpreted the ops message as he had braking power...just that the pedal didn't return to normal. But, yes...a loss of brake pedal is most often either a bad master cylinder or major leak/loss of fluid. Need more specific info, I guess.

 

[koda2000]

After sitting for 6 years with old brake fluid (who knows how old) I'd guess you have rust in the master cylinder (and no doubt throughout the braking system). The pedal sticking down is definitely related to a problem inside the master cylinder, which has a spring inside it to return the pedal after it's been depressed. Brake fluid absorbs moisture from the air. It's recommended that brake systems be flushed every 2 years, but most people don't do this. The moisture lowers the boiling point of the brake fluid significantly and allows rust to form in the brake system. Minimally I'd replace the master cylinder and flush the old brake fluid, but don't be surprised if you also encounter sticking calipers and ABS pump problems.

 

[SupaSwope]

Im probably not as experience as someone that will chime in. But I will give my 2 cents. I have re did most of my brakes on the gen 2 explorer.

The obvious first to things to check would be the pads and fluid level. If the pads are in good shape, its possible the fluid has gone bad by not having a good seal on the master cylinder. Brake fluid absorbs moisture from the air around it and generally you would replace your fluid within 5 years of having a vehicle anyways. If the pads are good, and if the fluid is good or you replace the fluid and is still a problem, there could be a leak in the lines. If theres no leak, Then we move on two the two last culprits.

Master cylinders usually don't go bad but they can, I replaced mine when I got my truck for the hell of it when I redid my breaking system. So When I did all that work to my truck I was still not satisfied with the stopping power. The guy at my shop ended up telling me that's it for the truck which I kinda agreed, I was trying to get my brakes to act like anther vehicle and its just not gonna happen there all different. The guy ended up sharing some information with me on how a bad brake booster feels, They can fail in two different ways, One was the pedal you wont be able to move it, Also a booster can fail by one of the seals where the pedal presses not creating any pressure for the master cylinder. When you press on the brake are you hearing that whooshing sound, of the air moving in and out of the booster? That could maybe help knowing if the booster was bad.

I hope this information helped some.

 

[triplej1954]

As far as the brakes go, it does have normal stopping power. Not an issue with that. As far as googing it, I have. What came back was parking brake issues, no matter how I worded it. As far as the brake system goes. Plans are to replace all the brake parts except the lines, rotors, and master cyl. May have to include it.

 

[koda2000]

As far as the brakes go, it does have normal stopping power. Not an issue with that. As far as googing it, I have. What came back was parking brake issues, no matter how I worded it. As far as the brake system goes. Plans are to replace all the brake parts except the lines, rotors, and master cyl. May have to include it.

FYI: The metal rear brake line is a common failure point (due to rust), so you might want to include that too.

 

[Rick]

I did some searching on some other Ford forums and found that the booster has a return spring in it. Replacing the booster solved the problem in a few of the cases that I came across.

 

[triplej1954]

thanks for the info. One thread I found suggested hooking a bungee cord to the brake pedal. Don't think that is how Ford designed it to work.

 

[koda2000]

thanks for the info. One thread I found suggested hooking a bungee cord to the brake pedal. Don't think that is how Ford designed it to work.

Talk about redneck engineering...