Jump to content

Disc Brake Conversion on 68 Delta 88


Guest Mocephus
 Share

Recommended Posts

Guest Mocephus

OK folks, for those interested, I'm going to go over the steps on converting front drum brakes to disc using a kit I purchased from www.scarebird.com. This conversion is the same for all full size Olds from 1965-1970, except the Toronado.

I decided to use the conversion kit from Scarebird due to having purchased a rear disc brake kit from them for my 1987 442, years ago. Even though I STILL have not gotten around to doing that conversion, I was impressed by the quality of the brackets. Once I heard about their Full Size kit, and remembering the hell I went through trying to find original disc brake parts, I decided to give them a try once again. The price was a little steep at $295, but other kits I found afterwards were higher than that and didn't seem to have the convenience of off the shelf parts, Wilwood for example.

Keep in mind, these guys build their kits around the off-the-shelf theory, meaning that while the bracketry and hub are custom made, the parts that actually wear over time are common items at any local auto parts place.

So, what do you get in the kit? A well made, plated set of caliper brackets, a set of custom hubs (hello floating rotors!!), 2 replacement upper mount bolts with hardened washers and a list of the parts you need to finish the kit (calipers, bearings, seals, brake hoses and rotors). Oh, instructions too, of course.

After receiving the kit, I started searching around for the remaining parts. Sure, I could have gotten everything local, but I found cheaper prices on the internet (rockauto.com for example had AC/DELCO rotors delivered to me for right at $70 for both) and I also found my local parts store offering a discount if you purchased online and picked up the parts locally. All told, I spent about $195 on the rest of the parts needed to finish the kit.

Here's how it lays out:

Calipers and pads are from a 69-72 Cutlass ("A" Body, easily found)

Wheel bearings are the same as my car's original, but also fit up to '76 Full Size Olds and other GM

Wheel seals from a '77 Full Size Olds

Brake hoses from '71-'76 Full Size Olds

Brake hose banjo bolts are from the aformentioned 69-72 Cutlass

REAR rotors from a '75 Thunderbird (which is the same for some other Fords and Lincolns up to '79).

Note:

The rotors are made for left side and right side, meaning the internal fins are angled to act as a "squirrel cage" design, thereby cooling a little better than just straight fins, but must be used on their corresponding side.

While I'm aware this conversion isn't factory, I was at least glad that most of the parts, while not original for my car, were from other Oldsmobiles. I'll just have to live with Ford rotors :)

I'm in the middle of organizing and uploading the pics. Once done, I'll continue on with the instructions.

Edited by Mocephus (see edit history)
Link to comment
Share on other sites

Guest Mocephus

Pic 1

The subject, my 1968 Delta 88 Holiday Coupe. I've grown weary of the front drums always losing adjustment, fading fast in the hot Florida heat... time to go....

Pic 2

The kit from Scarebird includes what you see here, times 2 for both sides. Notice the hub, that's one heavy duty hunk of metal. The bracket looks well made with nice straight edges and smooth welds. The bolt has had it's head shaved down for clearance purposes with the rotor (you'll see later) and the hardened washer is there so the plate doesn't distort from torquing the bolt to 75ft. lbs.

Pic 3

Here's the kit, along with all the pieces needed for each side.

post-45367-143138249572_thumb.jpg

post-45367-143138249593_thumb.jpg

post-45367-143138249612_thumb.jpg

Edited by Mocephus (see edit history)
Link to comment
Share on other sites

Guest Mocephus

The hubs come with the bearing races already installed, probably from when they were machined, however, the new bearings come with new races. I've always been told to replace the races when replacing bearings due to them being matched. Some people disagree. You decide. I went ahead and replaced the races, but won't go into detail about that. If you want to know how, pm me.

Pic 1 and 2

Before disassembling the car, do a couple of things beforehand, like pack the bearings. I used a bearing packer from Lisle and high temp synthetic grease. Put the bearing in with the taper going down, place the top on the bearing and push down, while rocking slightly back and forth. Grease will be forced through the bearing and out the top. Do this for both the front and rear bearings, for both sides.

Pic 3

Once packed, coat the outside with grease as well.

Clean out the inside of the hub with some brakeclean or laquer thinner. Pack the inside of the hub generously with bearing grease, the races also. I like to build a small wall of grease right behind the races, to help hold the grease in the bearings. Place the rear (big) bearing in the back of the hub, grease the rubber wheel seal around it's outer and inner edges and carefully tap into place until flat with the hub. I used a socket that was the same size as the outer edge, 2 1/4 inches, I think. You can do it without, but only tap on the outer edge. Don't put the front in until you are ready to mount the hub on the spindle.

post-45367-143138249631_thumb.jpg

post-45367-143138249649_thumb.jpg

post-45367-143138249666_thumb.jpg

post-45367-143138249683_thumb.jpg

Edited by Mocephus (see edit history)
Link to comment
Share on other sites

Guest Mocephus

Pic 1

Time to start the disassembly process. I decided to show the Driver's Side, since the speedometer is driven from there and has some special parts. Passenger Side is similar, but uses basic parts that most people are familiar with. I've noted where there are differences between the two.

Jack up the car and put on jackstands. Don't forget to chock the rear wheels. Remember, safety first. I left the jack under the lower control arm for safety sake and also to keep the suspension slightly under tension. This gave me some slack in the brake hose, which, as you will see later, came in very handy. Remove the wheel (Oh Joy!!! One stud broke!!! No matter... the new hub comes with brand new studs!!!). Remove the grease cap by using a small, flat screwdriver and tapping it between the cap and hub. Once you get a small gap, start prying around the entire edge to remove. It's VERY important that you do NOT lose this cap, or damage it (remember...speedo...).

Pic 2

This is the inside of the cap, showing where the speedo cable is driven from as well as a static arrestor. Keep in mind, this is only for the Driver's Side. The Passenger's Side has nothing inside it. Clean all the old grease out of it.

Pic 3 and 4

Driver's Side: Since the speedo cable goes through the spindle, there is no cotter pin holding the spindle nut on. There is, however a clip that uses the slot in the spindle to hold the nut from coming off. Carefully remove the clip and unscrew the nut. Remove the thrust washer and bearing by tilting the entire drum assembly slightly. It will force the bearing out. Pull the drum assembly straight off the spindle. If it won't come off, you might have to back off the brake shoes by sticking a screwdriver through the adjusting hole in the drum and backing off the star wheel (see lower part of Pic 5). Clean the clip, spindle nut and thrust washer of all old grease. Passenger Side: There is a cotter pin that holds the nut from coming loose by going through it and the spindle. It needs to be straightened first, then pulled from the spindle. The nut can then be removed. The cotter pin should not be reused.

Pic 5

Here is the brake backing plate with the drum removed. Don't bother taking off the individual parts. The whole backing plate with everything on it will come off as one piece.

post-45367-143138249701_thumb.jpg

post-45367-143138249718_thumb.jpg

post-45367-143138249735_thumb.jpg

post-45367-143138249753_thumb.jpg

post-45367-143138249771_thumb.jpg

Edited by Mocephus (see edit history)
Link to comment
Share on other sites

Guest Mocephus

Pic 1

The top backing plate bolt might have a tab of metal bent over it to hold it in place. Use a flat screwdriver and a hammer to straighten it out.

Pic 2

Using a 13/16" socket on a breaker bar, loosen the top bolt. I used a 4ft. floor jack handle on my breaker bar for extra leverage (remember, this bolt hasn't been turned in 40+ years). The bottom 2 bolts have nuts on them. Use a 7/8" wrench jammed against the lower control arm for the nuts and the 13/16" socket on the front. Again, loooong breaker bar recommended. Hold on to the lower nuts, bolts and washers, you'll reuse them. The upper gets replaced with the one in the kit.

Pic 3

The backing plate is now loose. If you have the suspension compressed enough (like I did with the jack), you should be able to manuever the whole assembly off without removing the brake hose. I purposely did it this way so that I didn't have to open up the hydraulics until the last possible second.

Pic 4

Hang the backing plate down and towards the engine, basically out of the way. You'll remove it later, once everything else is done.

post-45367-143138249788_thumb.jpg

post-45367-143138249805_thumb.jpg

post-45367-143138249822_thumb.jpg

post-45367-143138249839_thumb.jpg

Edited by Mocephus (see edit history)
Link to comment
Share on other sites

Guest Mocephus

Pic 1

Time to clean..... wipe off all of the old grease on the spindle. Use a little brakeclean to assist. DO NOT use anything abrasive, as the spindle surface is machined. Clean all the way to the back of the shaft and the step up, as that is where the bearing seal rides.

Pic 2

The metal around each bolt hole needs to be perfectly flat before mounting the caliper plate. I used a wire wheel on a drill to remove any corrosion and built up dirt. Spray the upper hole with brakeclean to get out any crud that might have accumulated during the cleanup process. Thread the new top bolt into the steering knuckle top hole to check for thread smoothness and to also help remove any remaining brakeclean. Use a paper towel to make sure the threads are clean, as you will need to use Locktite on it.

Pic 3

Place the caliper plate on the steering knuckle with the square bulge facing out. The arms that the caliper mounts to should be facing the rear of the car. If not, switch to the other plate.

The bottom bolts have 2 washers each. The thick washer goes between the head of the bolt and the caliper plate. The thin washer goes on the back. Notice the bolts need to go through the plate, steering knuckle AND the steering arm. The washer goes on after the steering arm, before the nut. Do not tighten yet.

Put the hardened washer on the new top bolt, along with some blue Locktite and thread into the top hole. Now tighten all bolts down. Per Scarebird, the top is tightened to 75ft. lbs. and per the Factory Service Manual, the bottom 130ft. lbs.

Pic 4

All mounted up and ready for the caliper....

post-45367-143138249857_thumb.jpg

post-45367-143138249875_thumb.jpg

post-45367-143138249892_thumb.jpg

post-45367-14313824991_thumb.jpg

Edited by Mocephus (see edit history)
Link to comment
Share on other sites

Guest Mocephus

Pic 1

The rebuilt caliper came with new slide pins, but they were not greased. Remove the slide pins and grease the rubber in the calipers with a SMALL amount of bearing grease. There is a collar in the back caliper hole that can be pushed out (with a bit of effort). Grease the rubber in that hole as well, again sparingly (you don't want that grease getting all over, it'll ruin the pads).

Place the caliper on the mounting plate and insert the slide pins through the caliper, through the plate and into the other side of the caliper. I did this for clearance reasons explained next...

Pic 2

I noticed the caliper and the mounting plate arms were too close together (probably from the plating) and were binding. I removed the caliper and with a flat file, removed a very small amount of material from the bottom and top of the caliper bracket. I removed just enough to fit a single piece of paper between the caliper and the mount, once mounted. Once you are happy with the fit, remove the caliper and set aside.

Pic 3

Grease the spindle with wheel bearing grease (generously). Don't forget the surface where the seal rides.

Pic 4

Make sure the hub is packed with grease. Place the hub on the spindle as straight as you can and push all the way back. The new seal fits a little snug on the back collar, so you might have to push a little hard. Fit the new front small bearing on the spindle and push into the hub. Place the flat thrust washer on the spindle so that the tab lines up with the slot in the spindle. Pack grease around the outside of the bearing and washer.

Pic 5

Thread the bearing nut onto the spindle and hand tighten as much as you can while spinning the hub.

post-45367-143138249927_thumb.jpg

post-45367-143138249944_thumb.jpg

post-45367-143138249961_thumb.jpg

post-45367-143138249979_thumb.jpg

post-45367-143138249996_thumb.jpg

Edited by Mocephus (see edit history)
Link to comment
Share on other sites

Guest Mocephus

Pic 1

Per the Factory Service Manual, using a socket and torque wrench, tighten the spindle nut to 30ft. lbs while spinning the hub. Once there, back off the nut 1/2 turn, then finger tighten.

Pic2

Driver's Side: Take the spindle nut clip and put the 90º bend through a hole in the nut, where the slot in the spindle is. If the slot is not aligned with any hole, tighten by hand until it does. The rest of the clip sits in the groove of the nut. Passenger Side: Use a new cotter pin through the nut, into the hole in the spindle and out the other side. Bend at least one leg of the cotter pin over the nut.

Pic 3

Fill the inside of the grease cap with grease. Paying close attention to the speedo cable and the hole it fits into (ignore for Passenger Side), install the cap in to the hub.

Pic 4

DO NOT HAMMER ON THE OUTSIDE DOME OF THE CAP. This will possibly jamb and ruin the speedo drive. Instead, use a socket or piece of pipe that is bigger than the dome but smaller than the flange and a hammer to tap it on. If those are not available, you can tap the flange carefully with a hammer lightly all the way around until the cap is flat against the hub. Not applicable for the Passenger Side, but hey, who wants a bashing in, crappy looking cap anyway?!?

Pic 5

Cap installed...

post-45367-143138250014_thumb.jpg

post-45367-143138250017_thumb.jpg

post-45367-143138250019_thumb.jpg

post-45367-143138250022_thumb.jpg

post-45367-143138250024_thumb.jpg

Edited by Mocephus (see edit history)
Link to comment
Share on other sites

Guest Mocephus

Pic 1

Alright!!! Time to get up, stretch, grab some lunch, relieve yourself.......

Go get the correct rotor for the side you are working on. Rotors usually come with some sort of coating on them so they don't rust when sitting on the shelf. You need to remove this coating, or it will destroy the brake pads. Brakeclean or laquer thinner work great. Clean the pad surfaces as well as the mounting surface (front and rear). Basically, the whole thing.

Pic 2

Once cleaned, place the rotor on the hub and use 3 lug nuts to hold the rotor in place. I threaded them on backwards, so the flat side is against the rotor instead of the tapered side.

Pic 3

The rebuilt caliper should have come with a spring clip that needs to be put on the inboard brake pad. The large part of the clip need to be facing the bottom of the pad. Install the pads in to the caliper. The outboard pad has 2 tabs that need to be bent down after installation. If there is a cap in the hole for the banjo screw, now is a good time to remove it.

Pic 4 and 5

Place the caliper/Pad assembly over the rotor/in to the caliper bracket. Insert both upper and lower caliper slide bolts and start the threads into the bracket by hand first. Tighten with an Allen wrench or socket to 35ft. lbs. Spin the rotor. It should turn with a slight drag, but not bind.

post-45367-143138250026_thumb.jpg

post-45367-143138250028_thumb.jpg

post-45367-14313825003_thumb.jpg

post-45367-143138250032_thumb.jpg

post-45367-143138250034_thumb.jpg

Link to comment
Share on other sites

Guest Mocephus

Pic 1

Grab the brake hose, banjo bolt and copper crush washers and assemble as shown. Notice the head of the hose has one side that's flat and a side that's indented. This will make the hose angle away from the caliper once installed.

Pic 2

Install the hose on the caliper. The hose will fit in between a "U" shaped area that is cast into the caliper.

Pic 3

Try to do the next few steps as quickly as possible to avoid losing a lot of brake fluid. Place a drip pan below the old brake hose. While holding the old hose with a wrench, remove the hard line, then...

Pic 4

while holding the hose, pry out the mount clip that holds the hose in place. Once this is out, the backing plate will be free from the car and can be removed.

post-45367-143138250036_thumb.jpg

post-45367-143138250038_thumb.jpg

post-45367-14313825004_thumb.jpg

post-45367-143138250042_thumb.jpg

Link to comment
Share on other sites

Guest Mocephus

Pic 1

The top of the hose has 2 tabs that fit into 2 notches of the frame bracket. Before fitting the hose in the bracket, thread the hard line into the hose until just snug, then back it off 1/4 turn.

Pic 2

Install hose in frame bracket, along with the mounting clip. Tighten hard line while holding the hose with a wrench.

Pic 3

YOU ARE DONE!!! Well, OK, almost. Time to bleed the brakes. Remove the brake bleed screw. Have an assistant SLOWLY press the brake pedal down and watch until fluid starts flowing from the bleed screw hole. Install bleed screw and snug down while fluid is still flowing. The caliper is now full. Have your assistant SLOWLY push the pedal down a few more times to get caliper adjusted, then bleed the line as normal. Install the wheel (might as well use new lug nuts on those new studs). Spin the wheel. Make sure there isn't any binding. Remove the jack stands and lower the car. Don't forget to remove the chocks. Check that the master cylinder is full. Test drive CAREFULLY to make sure everything is up to par. Check for leaks. ALL DONE!!!

Scarebird recommends going with a dual circuit, disc brake master cylinder. They also recommend plumbing in an adjustable proportioning valve in the rear line, if the rear brakes lock up to easily during heavy application. I'm going to drive it for a while to see how it does before going that route.

Test driving the car felt amazing!!! It feels much more secure and I barely have to touch the pedal now!!!! Oh, and no more pulling!!!!! Can't wait for the rear disc setup!!!!

Questions?

post-45367-143138250044_thumb.jpg

post-45367-143138250046_thumb.jpg

post-45367-143138250049_thumb.jpg

Edited by Mocephus (see edit history)
Link to comment
Share on other sites

Went ahead and stickied this thread, it's great! Now to see if Joe P can figure a way to incorporate it in the oldswiki somehow.

Any chance you can register over on classicoldsmobile.com and post this in the tech section? It's too good a thread to get lost in a shuffle somewhere, esp since it applies to ALL 65-70 full-size and I expect 59-64 owners can benefit too. Seems like I saw a 64 front kit on the scarebird site a while back. They've had the 57-64 rear kits available for a while.

Link to comment
Share on other sites

  • 1 year later...
Guest edward3412

Thanks for all the great info and pics. Just ordered my kit for my 67 Delta 88 today. Hope it goes as good as your seemed to if so I'll be looking for the rear conversion kit when it comes out. Thanks again

Link to comment
Share on other sites

  • 7 years later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...