Changing my own front brake pads + Rotors

[Felix_29]

Hi everyone, I want to attempt to do my own brake job on my Delorean. Change the front brake pads and rotors. Does anyone have any instructions with pictures I can take a look at? Also, does everyone here use the Ceramic type of pad that you can order from DMC and I think DPI. Or has anyone used another type of pad from a local auto supplier that is not Ceramic that won't run down the Rotor as fast? What is recommended?

Thanks everyone in advance.

Felix

[Delorean Industries]

I have a set on my car!

[Chris4099]

I don't have pictures, but here are the basic steps to give you an idea of what's involved:
1. Remove the calipers by undoing the two bolts (breaker bar may be required). Tip, turning the steering to one side will give you easier access. Set the calipers aside on top of the frame extension so there's no tension on the brake line.
2. Remove the large spindle nut (breaker bar will be required).
3. You can now pull the hub/rotor off. Note that if it's original, the bearings will probably fall apart. So it's a good idea to go ahead and just replace them when doing this job. You'll need to either have a machine shop replace them in the hub assembly (press is required) or you get get a refurb set from specialtauto.com with new bearings pressed in already (looks like DPI has them too).
4. Remove the 4 bolts to seperate the hub and rotor. Tip, if you don't have a bench vice to hold the hub, stick it back into the wheel while it lays flat on the floor. It will hold the hub in place while you unbolt the rotor.
5. You can now install the new rotor to the hub. Add loctite and torque bolts to spec.
6. Install the hub/rotor back onto the spindle. Add washer and spindle nut. There's a torque spec for the nut but it's so high I just used a breaker bar and got it on as tight as I could. Verify the hub/rotor spin freely.
7. Remove the pads from the caliper and compress the pistons in.
8. Place the caliper back on and torque the two bolts to spec. Install the new pads.
9. Reinstall wheel and repeat on other side.

[Bitsyncmaster]

A common mistake people make is compress the piston without opening the bleed nipple. That just forces all the dirty old brake fluid back into the lines or master and will cause problems later. Open the bleed and nothning gets forced back into the lines.

[David T]

Typically the rotors don't have to be replaced unless they are rotten, warped or deeply scored. You should also flush the brake fluid if it hasn't been done in the last 2 years.
David Teitelbaum

[Delorean Industries]

If the rotors are below minimum spec they should be replaced.

[DMC4719]

New disk thickness 12.7mm, Minimum thickness 11.7mm. Max machine per side .5mm.

Source: http://www.specialtauto.com/delorean-parts/brakes-rotors.html

[DMCMW Dave]

New disk thickness 12.7mm, Minimum thickness 11.7mm. Max machine per side .5mm.

Source:

For the USA audience, that is .500 inch (new) and <.460 inch (discard). Source - translated from the DMC Service Manual, in some location that I can't find at the moment.

[David T]

Found it. You have to look at the service bulletins. The first one, St-11-8/81 says you can't machine the rotors. It was superseded by ST-08-10/82 with the specs on machining. Minimum IS .461 but there is a minimum spec on each side. You can only take a maximum of .0197 on each side. You should not be machining the rotors if you can help it. If you have grooves you will not be able to save them unless they are very minor. If the surfaces are flat just scuff them up with a 3" abrasive disk chucked in a drill with 80# using a random pattern. This will remove any glaze and allow the new pads to "bed" in quickly. if you do have to machine them tell the shop to take the lightest cut they can. Parallelism is VERY important, so is lateral runnout.
David Teitelbaum




For the USA audience, that is .500 inch (new) and <.460 inch (discard). Source - translated from the DMC Service Manual, in some location that I can't find at the moment.

[DMCMW Dave]

I swear I've had cars in here with rotors at .300. I wonder what sort of machine shop would take them so thin. And why!

[Dangermouse]

I swear I've had cars in here with rotors at .300. I wonder what sort of machine shop would take them so thin. And why!

Possible from back on the day when people believed Delorean parts were made from unobtainium and you had to make do with what you had.

[Dangermouse]

Thanks for the rotor data. I have a set of pads on my shelf that I need to fit soon.

What is min thickness of brake pad?

[David T]

Happens when you have kids doing brake jobs and don't know what they are doing. Other reasons include:
Every time you do pads you cut the rotors no matter if they need it or not.
Taking big cuts when small cuts would do.
The rotors do not have the minimum thickness embossed on them as newer rotors are required to.
As seen, even Dave S had trouble locating the specs so how would a non-Delorean shop know what the minimums are? It is NOT necessary to cut rotors when replacing pads unless:
The pedal pulsates when braking
The rotor is grooved because the backing plate on a pad has touched the rotor and you can remove the groove without busting the minimum thickness. Some shops just do rotors as a matter of course. They have to pay off that brake lathe and can charge the customer more. The other thing they know is eventually they will be selling that customer new rotors too!
David Teitelbaum



Possible from back on the day when people believed Delorean parts were made from unobtainium and you had to make do with what you had.

[82DMC12]

I swear I've had cars in here with rotors at .300. I wonder what sort of machine shop would take them so thin. And why!

Duh, it's because they are for a DeLorean which is impossible to get parts for now so you make do with what you have!
:banghead:

Andy

[DMCMW Dave]

What is min thickness of brake pad?

That one is actually in one of the factory recall notes - they specify 1/8 inch but as they are bonded pads, they are actually OK until you hit metal. Then it's too late! So 1/8" is a good guide for an inspection number.

[David T]

The reason you do not want to go all the way down to the backing plate is that pads do not always wear evenly. One side of one pad may be 1/8 and the other 0/0. Pads are a lot cheaper than rotors so even if you have a little more than 1/8 you should be changing them. You must do them in sets, ie, both front calipers and/or both rear calipers. You never do only one wheel. Typically you change the fronts twice as often as the rears. You should be inspecting the pads every oil change or every year. if you have riveted pads 1/8 is not enough but I have never seen riveted pads on a Delorean (at least not yet)! You should also be checking the E-Brake pads too.
David Teitelbaum




That one is actually in one of the factory recall notes - they specify 1/8 inch but as they are bonded pads, they are actually OK until you hit metal. Then it's too late! So 1/8" is a good guide for an inspection number.

[Lwanmtr]

A common mistake people make is compress the piston without opening the bleed nipple. That just forces all the dirty old brake fluid back into the lines or master and will cause problems later. Open the bleed and nothning gets forced back into the lines.


But wouldnt this require you to do a complete bleed on the system after changing pads?

Wondering because I never opened bleed nipple on the other cars I've done pads on and never experienced any issues. Getting ready to do this on my car, since I have the wheels off while I clean up the frame n stuff underneath.

[David T]

But wouldnt this require you to do a complete bleed on the system after changing pads?

Wondering because I never opened bleed nipple on the other cars I've done pads on and never experienced any issues. Getting ready to do this on my car, since I have the wheels off while I clean up the frame n stuff underneath.

You do not have to open the bleeder nipple to retract the pistons. If your brake fluid is that nasty you should flush it BEFORE doing a brake job. What causes problems is when the piston gets corroded (from the nasty brake fluid) and the corroded part of the piston gets to the square "O" ring seal. The seal can't seal well over the corroded part so you get leaks. If the brake fluid is bad you should figure on rebuilding the calipers and the master cylinder. Don't forget the clutch hydraulics if you have a 5-speed. The fluid in both systems should be flushed out every other year whether you use the car or not.

[Lwanmtr]

My fluid is fine...just have the wheels off, so putting on new pads.