MGB Front brakes upgrade :)

This Saturday was given rainy... But was not in the end, so I have been lucky.
What was I planning to do outside?
... Rework the front brakes on the B! :)

I received from the previous owner who bought the car in 1985 all bills and receipts for all works performed on the car (one of the main reasons I have bought this car).

In the service history, the front brake pads were last changed in... 1993. I have no evidence that the discs have been changed, so I assumed they are from before 1985 (!).

I was intending to change discs and pads for some time now, especially as I was feeling braking was less efficient lately. Not bad, but less efficient.
Since 1993, the car has only done 14000 miles, so that should not be too bad.

Here follows a small tutorial and comments about servicing the brakes.

What I am going to do

Change the front plain discs by uprated EBC grooved and drilled ones.

Change the pads for EBC greenstuff ones.

I have bought a kit "+25 Braking upgrade kit H592" from MGOCspares: HERE

I have chosen this kit as it fits with standard standard MGB brake calipers and wheels.

This kit also contains pins, clips and locktabs and the oil seals between the wheel axle and the brake discs (item 90/ ref GHS101).

Finally, as you are not working in this area everyday, I have taken the opportunity to change the dust covers and put new stainless steel backplates, ref BTB412S and BTB413S, also bought from MGOCSpares: THERE

No need to change the brake hoses or wheel bearings as they are still in good shape (and let's keep some fun for later!).

Jack the car

First of all, you need to securely jack your MGB, using a hydraulic jack and a couple of stands. You do not want to see your car falling on you while you are working under/ around or falling on the floor without front wheels on it...

Keeping it simple:

• Loosen the front wheel nuts (this needs to be done while the wheels are in contact with the ground...). Do not remove the nuts yet! I am using the 21mm socket from a wheel brace. 
• Place the hydraulic jack under the front crossmember. 
• Then lift up enough to have enough space to install the stands under each frame rails.
• Once the stands are installed your stands, slowly lower the hydraulic jack so that the car gets supported by the jack stands.
• Leave your hydraulic jack touching the crossmember as an additional security, but remove the lever (keep it just on the side of the jack), as it is a trip hazard as you are walking around your car totally focused on the work you have to do.

Remove old parts

Remove the wheel nuts and the wheels.

You might want to thoroughly clean your wheels, inner and outer sides, from all the backed brake dust and dirt ;)

Disconnect the caliper from the stub axle assembly. The caliper is attached by two 5/8" bolts secured with a locktab: first unfold the locktab and remove the bolts.

You will need to suspend/ block/ support the caliper by any appropriate mean (be creative!).

Once the caliper is away, remove the end cap at the extremity of the wheel hub.

That will give you access to the wheel hub castellated nut (1-1/8"). The nut is secured on the wheel axle with a pin. This should be full of grease (and that's a good sign).

Remove the pin, using pliers for example, and next the 1-1/8" castellated nut with the appropriate socket (I tried with an adjustable wrench with no success). This should not be torqued like crazy and nearly come off by hand.

Next, you will need to remove the washer/ bearing and spacer(s) that are now free. Be careful, no dirt or foreign objects shall get stuck there... Unless you want to clean everything and reapply new grease.

The wheel hub with the brake disc can be now extracted. This should not oppose resistance, except the assembly might be a bit heavy. One metallic collar might stay on the axle. Note the way it is installed on the axle and keep it on the side.

Now, you will have access to the backplate (stone guard/ dust cover).

It is hold to the stub axle assembly by four 9/16" (or 7/16", sorry I have a doubt), with 4 locking washers.

Remove the dust cover, and spray/ apply some cleaner/ degreaser and let it do the job for you.
Please note the jack stands and hydraulic jack in place.

During this time, let's remove the old brake disc from the wheel hub.

It is assembled by four 3/8" bolt & nut assemblies.

To undo the disc, step on it and use a long wrench to get enough force to loosen the nuts.

From there, no difficulties, once the nuts are loose, you can remove them by hand and take off the brake disc from the wheel hub.

And you are finally done! Lots of parts all around the place and your car cannot be used anymore!

... OK, time to fit the new parts, you may need your car to go to work tomorrow (if yours is a daily runner like mine) ;)

Install the new backplates

Finish the cleaning started before (degreaser/ cleaner applied), wiping off the remaining dirt and grease.

Backplates are not symetrical, so you cannot invert them.

Put the new one (shiny stainless steel!) and screw the bolts by hand. Don't forget the locking washers.

Torque the screws between 17 and 19 lbf ft (23 to 26 Nm).

Install the new front discs

Position the new disc on the wheel hub. Be careful, if you are installing grooved and drilled ones, like me, there is a correct way to install them. The picture below is from the passenger side (Right Hand Drive/ UK). Left = front of the car

Tighten by hand the 4 bolts/ locking washers & nuts assemblies, and finish by torquing the nuts from 40 to 45 lbf ft (54 to 61 Nm). You may need another spanner or ratchet/ socket on the bolts to prevent them from rotate.

Before putting back in place the wheel hub on the axle, let's just change the oil seal on the stone guard side of the wheel hub assembly (there is only one seal, you cannot miss it). Remove the old one by any appropriate mean, just be careful to not damage the wheel hub itself, otherwise you will lose the oil tightness. Install the new one and bring it to the same level as the wheel hub using a hammer (gently!).

Clean the brake disc using either brake cleaner or other degreaser (I am using MEK).

Time to install the wheel hub on the axle. By order:

• The metallic collar, flat side facing you
• Wheel hub, the oil seal will come around the metallic collar
• The spacer(s)/ shim(s)
• The conic bearing
• The flat washer. This one has a dent to prevent its rotation
• The castellated nut

Once everything is in place after you have been jiggling it around, the castellated nut has to be torqued between 40 and 70 lbf ft (54 to 94 Nm).

Align the castellated nut with pin hole so that you can finally put back in place the pin, and fold the extremities.

Install the end cap, using a hammer. Be gentle here again.

Clean again the brake disc.

You just successfully installed new brake disc on your MGB! Congratulations!

Change the brake pads

You might need something to support the brake caliper while you work on it.

First step is to remove the old pads:

• Unfold the locking pins extremities.
• Remove the pins using pliers.
• That will give freedom to the clips... They should fall on the ground.
• Remove the pads, by hand should be enough but use pliers if necessary

Next step is to create enough space between the caliper pistons to be able to install the brand new pads, which are thicker.

Open the bonnet and open the brake fluid tank.

Go back to the caliper, and apply pressure to each caliper piston using a F-Clamp.

The pistons should go back in the caliper progressively.

Be careful, pushing back the pistons in the caliper means brake fluid will be pushed back in the tank.

Keep an eye on it, and prevent any excessive brake fluid to overflow (hydraulic fluids are highly corrosive, and will basically attack everything around (paint, rubbers, etc etc).

Now that the pistons are pushed back in the calipers, put back the caliper on stub axle assemblies.

Use new locktab and insert the two 5/8" bolts back. Torque them between 40 to 45 lbf ft (54 to 61 Nm) and fold the extremities of the locktab to secure the bolts. 

Finally, the new pads can be installed!

The EBC greenstuff for the MGB are asymmetric:

The long curve will go to the top once the caliper is installed on the car.

How to install new pads:

• Apply a uniform layer of copper grease on the back of the pads. The grease will avoid your brakes to squeal later. Be careful: no grease on the front of the pad, otherwise the car will just not brake at all. Probability of car crash = 100%
• Insert the new pads in the caliper, friction surface close to the disc, copper greased side facing the caliper pistons.
• Using copper grease, apply a bit of grease on the extremity of the pins.
• Hold a clip in place on the brake pads, long side to the centre of the caliper, short side toward the outside, and insert the pins through the caliper.
• Once the pins are inserted, fold the extremities so that pins cannot move away under vibrations

Clean once again your discs using brake cleaner or equivalent to be sure no dirt or grease is left there.

You have just installed new pads! Well done!

Finalisation

Put back your wheels on your car. 

Tighten the nut lugs by hand and using the wheel brace as much as you can.

Lift up your car using the hydraulic jack still in place under the front cross member.

Remove the jack stands, and slowly get your car back on its wheels.

Remove the hydraulic jack from under the car and tighten your wheel nuts using the wheel brace.

Control the brake fluid level in the tank. Put the cap back on the fluid tank, and... close the bonnet!

Bravo, it is finally over. You just have to clean all your tool and discard the old discs and pads small parts!

That can take some time when you are not used to do this kind of servicing (plus you might be extra careful as me to avoid any damage), so plan at least 5h the first time you will be doing this.