Need expert advice on finishing 94 Celica brake job Options

[Langing]

JULY 22 UPDATE: "BRAKE JOB" FINISHED. (See comment of today's date.)

JUNE 2 UPDATE: REAR BRAKES FINE NOW; FRONT RIGHT STEERING KNUCKLE DEFINITELY BENT (AT THE EARS); SEEKING ANOTHER KNUCKLE.

MAY 28 UPDATE: NOW WHAT? THE REAR WHEELS ARE LOCKED BUT THE PB IS DOWN! WHAT THE HECK IS GOING ON?

MAY 27 UPDATE: SATISFIED THAT THE REAR DRUM BRAKES ARE NOW FUNCTIONING PROPERLY; PROBLEM DEFINED DOES NOT AFFECT THE BRAKE AT ITS PROPER ADJUSTMENT OPERATING POINT; MOVING ON TO NEXT TASK

MAY 23 UPDATE: REAR DRUM BRAKE PROBLEM DEFINITION IS NARROWING SUCH THAT AN EXPERT MIGHT BE ABLE TO HELP ME (SEE LAST POSTS)


This is my first experience doing such an extensive job on my Celica, and I have the Green Books (FSM). Everything looks beautiful (to me), have photos.

I have finished replacing/rebuilding all parts of the brake system -- meaning at all four wheels (including new hardware, hoses, wheel bearings, etc) and am ready to put her back on the road, but . . . with all new shoes, pads, drums and rotors, how can I know they are working properly? I’ve already discovered a couple of assembly mistakes I had to correct, which tells me there may be something else I am missing?

First known issue: because I don’t have a vernier caliper longer than 6”, an AMPRO T71558 Brake Drum Resetting Gauge will arrive on Friday so I can set the ‘clearance’ between the shoes and drums at the rear. Beyond that I have some confusion on how the parking brake works to maintain the proper clearance, given the initial setting of the rear brakes. I want to be totally clear about what I am doing so I am not making a stupid but costly mistake.

For example: the manual says to verify that the parking brake levers (on the rear shoes) turns the adjusters (they do) and then to minimize the length of the adjusters (I did), then install the drums and pull the parking brake lever (in the cabin) all the way up until a clicking sound can no longer be heard (did that as well). The very next procedure is to check shoe clearance, but the last step left the parking brake on? And I was thinking that engaging the parking brake and then releasing it was the cause of the adjuster turning, and that it turns only by just one gear tooth distance. All that said, the manual has me just setting the initial clearance, popping on the drums and tires I'm good to go. Is that really all I need to do to make sure the rear breaks are functioning properly?

Second issue: with new rotors and pads on the front disc brakes, there isn’t a lot of free space in the caliper bracket and there is a scraping sound when I turn the rotors by hand, so there is obvious interference. I don’t know whether the slide pins are not working well, since the calipers aren’t sliding in and out when hand manipulated, or are they just supposed to rub together until enough friction material wears off that they can begin to have enough space to work once the car is on the road? How do I check them BEFORE I put her on the road, so I can be certain they are working properly?

My inexperience has me ready to go, but dead in the water.

This post has been edited by Langing: Jul 22, 2014 - 11:06 AM

[Langing]

THANK YOU richee3! I think that's going to speed up the process, so let me test it out.

Ok,what I want to show now is how I knew that something was really messed up in my right front disc brake (other than hearing all the racket the wheel was making when I tried to drive on it)

Since the loud sound seemed clearly to be coming from the right front, that's where I started looking. Twice during my checkout regime, when I popped off the tire after driving, I discovered a pad support plate in the lower inside position that looked loose in its slot in the torque plate (caliper mounting bracket).



The first time I just hammered it back in place, thinking, good, I've fixed another problem. The second time it happened, I dug deeper. That's when I saw the ugly scarring on the backside of the brand new rotor.



At first I was thinking that the top part of the torque plate was interfering with the rotor, but then I took the inside brake pad off and that flipped out the pad support bracket at the bottom position. All of a sudden I could clearly see a mound of rotor dust that had accumulated in the recess where the pad suport plate was supposed to be. More than that, I could see that the rotor and the mounting bracket were coming together at a small acute angle, a sure sign that they were not parallel to one another, and I have a very strong feeling that parallelism is a requirement in this situation.

IMO something is wrong with the mounting surface(s) of the caliper mounting bracket, possibly something I had messed up when I was aggressively cleaning them prior to painting. I wasn't intending on painting, but when I had them almost bare metal clean, I watched a Youtube vidwo and heard a guy saying that you never want to leave clean metal exposed to the elements; it causes immediate rust to form all over it. When I couldn't get clear high temp spray paint, I settled for black. Now I rather like the effect. Funny how I stumble into things.



Evidently, it must have been when I was backing up that the rotor pushed the pad support plate out of position each time.

So, there it was, clearly the caliper mounting bracket was causing the interference, as it was bolted on. So, I wanted to come back here to show the experts what I had discovered and ask them what's the easiest (or correct) way to fix this problem.

While waiting, I moved along to the left front wheel to check it out, and of course expected to fix another sticky slide pin with another swelled bushing. I was not disappointed. Sure enough, that lower slide pin with the rubber bushing was locked as tight as the right side had been. So, I fixed that and regreased the upper slide pin as well. Then I examined both sides of the rotor, the mounting bracket, the pad support brackets, everything about that disc brake assembly that I could think to check. I even caused the rotor to revolve so I could check for any bad sounds. It looked and sounded about as perfect as I could have hoped. Yes, there was a very slight grinding sound, as the pads were lightly touching the rotor. So, I torqued down the caliper bolts and the lug nuts and declared that wheel finished!

Still feel a bit far from being complete, but my to do list is now fairly short:

• wait for the drum clearance tool to arrive (should be today)
• set the drum clearance to 0.024"
• take up the slack in the parking break
• set all the brake pedal parameters to book values
• test the booster
• finish fitting the right front caliper mounting plate so it no longer interferes with the rotor
• take the car out to 'embed?' the brakes (get friction material onto the drums and rotors)
• declare victory and write it up

Let me make a prediction. I am guessing, and it is ONLY a guess (bases on experience), but I almost know for certain that I am going to need more help, so I am going to keep this thread going until I am completely done. This is, to me, a relative novice, a major project. Thanks to everyone who is helping.