# Brake pad replacement



## wine (Feb 23, 2005)

I'm replacing the front pads on my 97 Sentra. Is it necessary to put the retaining clips?

The caliper pins do not thread in, what should I do?


----------



## ReVerm (Jan 13, 2003)

wine said:


> I'm replacing the front pads on my 97 Sentra. Is it necessary to put the retaining clips?
> 
> The caliper pins do not thread in, what should I do?


If by retaining clips, you mean the flat metal clips that go between the pads and the brake member, yes, you do need them. Without them, you run the risk of having the pads get caught and not engage/disengage properly.

The caliper pins themselves don't thread into the brake member (they just go straight into the brake member and are held on by the little rubber boots), but the bolts that hold the caliper onto the remainder of the assembly should thread onto the pins pretty easily. If the thread on the inside stripped or something is wrong with the two bolts that hold the caliper on, you can get new hardware from any auto parts store.


----------



## wine (Feb 23, 2005)

*Please clarify*

:cheers: 
Let me clarify: I was referring to the retaining pins v - shaped pins. Can't figure out where they go. Already put pads on. The pads are already held by the flat retainers. 

The calipers bolts won't thread in. The piston is pushed into the caliper. Do I have to Press the brake pedal do the caliper bolts thread in?

Thanks for your help.


----------



## wes (Apr 30, 2002)

wine said:


> :cheers:
> Let me clarify: I was referring to the retaining pins v - shaped pins. Can't figure out where they go. Already put pads on. The pads are already held by the flat retainers.
> 
> The calipers bolts won't thread in. The piston is pushed into the caliper. Do I have to Press the brake pedal do the caliper bolts thread in?
> ...


Clarify more, are the holes lined up or are you saying you canot get the caliper down over the pads?


----------



## wine (Feb 23, 2005)

*more clarifying*

The holes are lined up. The caliper won't hold onto the pads because the caliper bolts won't thread in. I am assuming because of pressure in the system. The piston is push out of the pads.


----------



## wes (Apr 30, 2002)

wine said:


> The holes are lined up. The caliper won't hold onto the pads because the caliper bolts won't thread in. I am assuming because of pressure in the system. The piston is push out of the pads.


You lost me but if you press the brake pedal that is going to put more pressure in the system. You said that you pushed the piston in but have you hit the brake pedal since you did that? Put a clamp on the assembly and use that to try and get the bolts started.


----------



## ReVerm (Jan 13, 2003)

wine said:


> Let me clarify: I was referring to the retaining pins v - shaped pins. Can't figure out where they go. Already put pads on. The pads are already held by the flat retainers.


Ah, my mistake. Those v shaped pieces of wire are anti-squeal springs for your pads. Some brake pads have holes on the top of the pad so you can put them on there. They keep the pads separated from the rotor when you aren't braking and reduces the amount of noise that they make. You don't really need them, especially with some of these newer brake compounds which make very little noise as is.


----------



## Novelist (Jul 7, 2004)

*Spongy*

I just can't get my brakes (97 car) to work well. I bought new discs (aftermarket) and now fitted Raybestos linings which I believe are good quality. The brakes are ok at speed though the pedal pressure is a little heavy, but at low speeds they seem terribly spongy and it requires really stamping hard to stop in a hurry. A feeling as if they 'take time to come on properly'. There's no pulsations, the discs appear perfect. The pedal doesn't feel like there is any air in the system but I will bleed yet again. Any ideas?


----------



## ReVerm (Jan 13, 2003)

Novelist said:


> I just can't get my brakes (97 car) to work well. I bought new discs (aftermarket) and now fitted Raybestos linings which I believe are good quality. The brakes are ok at speed though the pedal pressure is a little heavy, but at low speeds they seem terribly spongy and it requires really stamping hard to stop in a hurry. A feeling as if they 'take time to come on properly'. There's no pulsations, the discs appear perfect. The pedal doesn't feel like there is any air in the system but I will bleed yet again. Any ideas?


Is the pedal travel the same at every speed, or does it decrease at speed?


----------



## ReVerm (Jan 13, 2003)

wine said:


> The holes are lined up. The caliper won't hold onto the pads because the caliper bolts won't thread in. I am assuming because of pressure in the system. The piston is push out of the pads.


Could you describe which bolt is not threading properly on this diagram? It'll make it easier for us to help you.










Note: Bolt #13 goes into caliper pin #1.


----------



## wine (Feb 23, 2005)

*Bolt #13*

I was talking about bolt #13 which goes into the caliper pin. Already done on driver's side. But on the passenger side, it will not thread in. Everything else is in place, the rotor, the pads, the other bolts. Bolt 13 is still sticking out. Pushed the brake pedal several times to make the pads contact. There is too much pedal travel. Please help. Thanks.


----------



## wes (Apr 30, 2002)

wine said:


> I was talking about bolt #13 which goes into the caliper pin. Already done on driver's side. But on the passenger side, it will not thread in. Everything else is in place, the rotor, the pads, the other bolts. Bolt 13 is still sticking out. Pushed the brake pedal several times to make the pads contact. There is too much pedal travel. Please help. Thanks.


Pushing the pedal pushes everything outward. Have you tried what I suggested?


----------



## Novelist (Jul 7, 2004)

ReVerm said:


> Is the pedal travel the same at every speed, or does it decrease at speed?


I think it's the same at all speeds.
Today, with more miles on the brakes, the car seems to stop better. It is worst when driving away cold, after a few miles it improves quite a bit.
I'm wondering now if these pads are quite hard and need warming up before they work well?
The previous pads were some garbage fitted by a garage. They produced thick black dust very quickly and faded right away after coming down a long hill! That's why I bought and fitted the pads myself this time. 
No doubt someone will think 'why doesn't he fit genuine Nissan pads'.
Well, I would, but Nissan wanted $80 a set. (Front pads only). NO WAY am I paying that much! I have never seen such tiny discs on a car before.
Thanks for taking the trouble to reply -

Clive


----------



## ReVerm (Jan 13, 2003)

wine said:


> I was talking about bolt #13 which goes into the caliper pin. Already done on driver's side. But on the passenger side, it will not thread in. Everything else is in place, the rotor, the pads, the other bolts. Bolt 13 is still sticking out. Pushed the brake pedal several times to make the pads contact. There is too much pedal travel. Please help. Thanks.


If that bolt doesn't thread into the caliper pin easily, there's either crap in the thread or the thread is screwed up. Since you're having this much trouble you may as well go to the auto parts store and get new pins and bolts (usually sold as a brake caliper hardware kit). It shouldn't cost very much and it should save you a lot of aggrivation in the future.


----------



## ReVerm (Jan 13, 2003)

Novelist said:


> I think it's the same at all speeds.
> Today, with more miles on the brakes, the car seems to stop better. It is worst when driving away cold, after a few miles it improves quite a bit.
> I'm wondering now if these pads are quite hard and need warming up before they work well?
> The previous pads were some garbage fitted by a garage. They produced thick black dust very quickly and faded right away after coming down a long hill! That's why I bought and fitted the pads myself this time.
> ...


The unusually long pedal travel (spongy brake pedal) is probably due to one of two things:

1. There's air in the lines and the brakes need to be bled again. If you haven't done it already, try the 2 man method and make sure that the person operating the bleeder screw closes it _before_ the flow stops (before the pedal hits the floor).

2. The brake pads you got are thinner than the ones that were on there before, and the brake booster preload needs to be adjusted. I have a feeling this is the problem in your case. Not all brake pads have the same initial thickness. Sometimes you will get new pads that start out so thin that the piston has to come out a few extra millimeters just to touch the brake pad. That extra space equates to a longer pedal travel, which is never good for a brake pedal. By increasing the brake booster preload, you can get rid of that gap and get your pedal back up to where it should be.

Here's the procedure, straight from the B14 FSM:









It's a pretty annoying procedure, especially if it's your first time doing it. When you get under there and look at the rear of the brake pedal assembly, you'll see a rubber boot coming out of the firewall connected to a threaded rod with a nut on it, and the bracket that the rod goes into (which is attached to the brake pedal itself). The more the rod sticks out of the bracket on the pedal, the less your booster preload. Loosen the lock nut, and turn the rod clockwise (with vise grips or pliers) to increase the preload, and counter-clockwise to decrease it.

The whole point of this is to find a happy medium. Too much preload and your brakes will drag. Too little and your brake pedal travel will be really long. I've found that the best way to find the "sweet spot" is to do this on a level parking lot/driveway: 
- Pull the handbrake up, make an adjustment using the above procedure, lower the handbrake, and see if I can get the car to roll by pushing it. 
- If the car does not roll, pull the handbrake up and lessen the preload. 
- If the car does roll, fire the engine, sit in the driver's seat, and test the brake pedal travel. 

Sometimes the difference between too much and too little preload comes down to 1/2 or 1/4 turn, so this probably will take you an hour or two the first time around. Take your time and don't try to rush it. The end result will be worth the trouble.


----------



## wine (Feb 23, 2005)

*Caliper Pin won't go In*

Here's the deal: bolt #13 does thread into caliper pin #1. It's now all one unit. The whole unit pin and bolt won't go into the caliper (the mounting bracket actually). The end of the caliper pin isn't threaded. It's got three flat sides and three round sides. So how does it go in?

All suggestions greatly appreciated. :hal:


----------



## ReVerm (Jan 13, 2003)

wine said:


> Here's the deal: bolt #13 does thread into caliper pin #1. It's now all one unit. The whole unit pin and bolt won't go into the caliper (the mounting bracket actually). The end of the caliper pin isn't threaded. It's got three flat sides and three round sides. So how does it go in?
> 
> All suggestions greatly appreciated. :hal:


The caliper pins are held onto the caliper mounting bracket solely by the rubber boots on them. They are not supposed to be "threaded on". They are greased up and inserted straight in until the rubber boot pops on. 

Bolt #13 and pin #1 should not be put together before you insert the pins into the mounting bracket. Both caliper pins should go into the bracket first, the caliper should go on top of that, and bolt #13 should go through the holes in the caliper and be threaded onto the inside of the caliper pins afterwards.


----------

