Hi all,

Finally decided to post on this, since it hasn't gone away. I recently overhauled the brakes on my 93' Civic DX hatchback with ~207,000 miles. I replaced one rear drum (other drum was in spec, and I cracked my replacement so couldn't use it), rear shoes and brake cylinders. I rebuilt the front calipers with new seals and boots, replaced brake lines all around, replaced front rotors with some cheap ones from AutoZone, and Hawk brake pads. I also replaced the master cylinder with a new OEM one. Unfortunately I kinda stripped the connection where it connects to the hardline (and one of the hardline connections too - those were way stuck), but I could get everything tight so I left it alone.

Problem I'm having: there is very little feedback from the brake pedal. It feels numb for the first 1/2" or so of travel and then gets very firm. I really have to push hard on it to get braking results. Furthermore I wouldn't consider the stopping distance too spectacular. My other car (83' RX-7) with similar disc/drum setup and smaller discs on the front stops much better with a more linear pedal feel. Obviously totally different cars, but I can't help but feel the braking is sub-standard on my Civic now.

I'd guess it's something with the brake booster, but the pedal feel was much more linear before I made all these brake changes and I didn't touch the booster - so I'm guessing I screwed something else up. I also get some shake on the front wheels when braking at highway speeds. All bushings on the front suspension are new and the steering rack has been rebuilt and is tight. Since I wasn't able to get a torque wrench on the compliance bushings I just guessed on how tight they should be, could it be that they're too loose?

Thanks!

 

Did your manifold vacuum check valve get turned around, by chance?

 

I'm not sure, I don't recall touching that. I'll look when I get home.

It could be I'm just imagining this, but I swear the braking was more linear and progressive before I made these changes. Also feel I need to press too hard on the pedal.

 

Your symptoms kind of point at a malfunctioning vacuum assist.

Did you bed in the pads properly?

 

I did a few stops from 30-40ish to 0. At first I had basically no stopping power, but after a few stops it felt driveable, but still not how I'd expect. I find it difficult to lock the brakes as well.

There's no reason to believe that other things aren't wearing out in the braking system, but I don't have much else to check. This car was in okay condition when I bought it, the previous non-enthusiast owner used it as his daily driver and did some maintenance to it, but brakes, suspension, etc. were fairly worn out.

 

I hate to ask massively basic questions.

But did you brake-clean the rotors prior to install?

what made you decide on a new MC? Was the old one malfunctioning, or were the old brakes just worn?

how did you crack the brake drum? any chance you did some damage to something?

 

I did not clean the rotors before hand. The only reason I went to a new master cylinder is because I felt I should due to the high miles, I wish I hadn't replaced it since it was probably fine.

I bought the car from a co-worker and he had some parts he was going to install, but never did. He had two new brake drums, but one was cracked, so I reused one of the old ones on the car (it was in spec). He also had some rotors, but they were too big, probably for an EX or whatever had larger front brakes. I drove the car around today in the mountains, and strangely the brakes felt better after driving for awhile, but still kind of a weird feeling. Like there's no feedback for the first part of the pedal travel (although it does slow the car), and then the effort gets much higher making it somewhat difficult to give it a medium amount of stopping. That's problem #1, problem #2 is the shake I get on the front wheels (not steering wheel) when braking at highway speeds. The only thing I could think is that the compliance bushings aren't torqued enough, but I don't want to end up cranking on them and stripping the control arms. I recently installed Si front control arms so that I can get a front swaybar in the future.

 

A huge part of your issue is that you did not clean the rotors beforehand.

The rotors come covered in some sort of lubricant to prevent rust.

You have to thoroughly brake clean the rotors before installing.

Try taking the pads and rotors off and cleaning them. Hopefully, the pads aren't soaked in that substance. You may need to sand off some of the oil laden pad surface.

Re-bed them per Hawk's instructions after doing this cleaning procedure.

They should vastly improve.

 

Okay, now I feel slightly foolish. Yea the rotors definitely had some black something or other covering them. I thought it was odd, but I was like okay whatever, they're just like that. I've installed rotors on other cars that had no covering, so I hadn't seen that before. Oh well.

I'll have a go with cleaning things off and see if it helps or not. Thanks!

 

If your hats and lips came with a black coating, then that's beneficial to stay...don't attempt to remove that.

I am more refering to the friction surface having an anti-rust lubricant on it. That lubricant needs to be sprayed off with brake cleaner.

The anti rust lubricant is kind of like...a waxy version of WD40. Its usually amber-ish in colour.

Anyway, good luck! Let us know if it worked out!

 

Okay, this covering was totally black, and it felt kind of matte-like. But it came off after driving a bit. I'll post back when I get a change to clean everything off.

Also, maybe it's worth replacing the check-valve? It's only 20$ new.

 

Maybe...but it's likely just a case of the slipperies. Check how the brakes work after cleaning them and go from there, would be my suggestion.

 

Okay, I'm kind of leaning towards the problem being the nut behind the steering wheel.

I took the brake pads off today and cleaned off the rotors with some brake cleaner. I didn't want to take the caliper bracket off so I just cleaned the visible section and rotated the hub to clean it all. I didn't notice anything out of the ordinary, and the pads didn't look soaked or messed up or anything. I put it back together and tried to really concentrate on what I was experiencing. I noticed in particular that more I used the brakes the better they felt and the less numbness in the initial pedal travel (which is annoying me). If I really shove on the pedal I can get the brakes to lock quite dramatically, although it feels like there's more travel then I'm used to.

I think the numbness in the initial part of travel, greater pedal effort and larger amount of pedal travel may just be the way the car is. This is only the second car I've owned without ABS, so my only other point of reference is my RX-7, which feels nicer, but it could just feel nicer. Maybe there's just less boosting on this car. Should I have adjusted the brake pedal after replacing the master cylinder?

 

I'm going to probably take a look at the rear drums over the weekend to see if they're the source of the problem. I drove the car on Wednesday and it still just feels "off" to me. I feel the brakes felt much more progressive before doing all this brake work. I know this is a vague problem, but it's hard for me to be more specific beyond what I mentioned above, and just the fact that I feel it's not how it should be.

On a related side-note, it drives me crazy that I rounded off one of the brake line fittings. Aside from just dealing with it and using pliers to deal with it in the future, what are my options for fixing it? The only options I can think of are making a new one from scratch (but I'll never get the factory bends correct), buying a decent condition used line or cutting off the fitting, put a new one on and re-flare the line. I find it very irritating to have something that I broke on the car. I like fixing, not breaking.

 

Huge clue, first check your brake fluid. I betcha you're not entirely bled, ie there's air in the brake lines. Having a little rust on the rotors, all this stuff is very very small relative to a gap in your brake pedal stroke. If the MC and BB were installed correctly, the first thing to check is your fluid, especially since you mentioned replacing the master cylinder. What size do you have? It says on the side, its a fraction, either 13/16, 7/8, 15/16 or 1. Did you bleed Right Rear, Left Front, Left Rear, Right Front in that order? Did you bench bleed the MC before installing it? I bet if you open the rear right bleeder and run a clear hose from there to the MC resovoir, you could just sit there pumping several dozen times and there may be a ton of air bubbles that come out.

Also, typical replacement parts do NOT require adjusting your brake booster, its something that's rarely ever done on our cars, even with modding and upgrading. So first check for air in your brake fluid, that will have the most dramatic effect on pedal feel.

 

Okay, someone tell me if I'm just crazy, or if this makes any sense at all.

I've noticed for awhile, that there is an noticeable sound coming from the rear passenger side when braking. I decided to try and adjust the handbrake. The rear passenger wheel drum drags much more than the driver side. I backed off the adjustment on the handbrake a lot, but no amount will prevent the passenger drum from dragging. I'm thinking maybe the drum is slightly warped which could be causing this? Anyways, after backing the adjustment off the braking felt much better and more linear. Does that make any sense, or is it all in my imagination?