Disc Brakes!!! It's a big one.

While everybody else is watching news coverage of Hurricane Sandy, I'm in the garage, getting something done:

I put the new brake master cylinder in (see previous post) to support this; the new front disc brake conversion!

There is nothing wrong with drum brakes, per se, except that it is weird to acutally see front drum brakes at all. Most manufacturers were changing over to front discs by about 1970, some 40+ years ago.

After removing the actual drum part, I saw just how worn out these brakes are. Total, total junk. I almost think this car sat in a lake for some time. All of this has to be removed down to the spindle.

I'll save the old parts in my garage, likely until my death, despite the fact that I will have no use for them, and they are readily and cheaply available, in far better condition, to anyone that might need them. This is what it means to be a car guy.

I'll disconnect the brake hose. Oh look, it's our friend, Mr. Vertical-Brake-Line-Loop again. How predictable. I believe we met your brother on the last post.

Most of the removal went ok. One big stubborn bolt required some, shall we say, persuasion. It's a monster 5/8" fine thread. I gave it a nice soaking with the acetylene torch. Then it came right off. Good ol' Mr. Torchy.

Finally we're down to the bare spindle.

 

Here is the new front disc brake conversion kit. The stock front brakes would need a total rebuild. And I have already determined that I'd need all new bearings too, since the passenger side wheel is so loose it is almost falling off the car. The cost of all new drum brakes plus bearings is nearly as much as the db conversion.
Here are all of our new parts laid out for inspection:

Oh, one more thing: The '58 has ball bearings in a race. Since they needed replacement, I wanted to do a conversion to tapered roller bearings too. They're better at handling side loading and have been the standard configuration since about 1960 until today. The cost of that upgrade made the db changeover a no-brainer; the db's come with tapered rollers standard.






This made Crispy cat very interested:

The stock spindle must be modified. There's always a bit of trepidation when you have to irreperably modify the stock parts, even for me. The new inner bearing ID is smaller than the spindle OD. A quick measuring confirmed a .004" interference. The kit instructions say to sand the spindle down. I used an emery cloth strip and sanded the spindle using a shoe-shine motion, until the bearing achieved a nice slip-fit.

Four thousands of an inch isn't much (unless there's interference, as we have here. Then it's a ton). The sanding goes quickly, and you have to be judicious. To get the correct slip-fit is important, so you want to sneak up on it, really. I hate to say it, but you have to have some experience to know when this is correct. I'm talking about getting this right to 1/1000 of an inch. If it's too tight, the bearing will get stuck on the spindle. If you remove too much material, you'll have a sloppy bearing fit. Your bearings will wear prematurely, and it will never be right. You'll have to find another 1958 spindle, and hope you don't ruin it too. No pressure.


I have the caliper brackets mounted. Pretty simple so far. The big scalloped part with 2 holes is where the new calipers will mount. You can see I have the inner bearing on there, all greased up nicey-nice. Pack your new bearings with as much grease as you can.

Here is the new rotor in place. At first I couldn't get the outer washer (shown) to fit right.

Here is the caliper mounted. Unfortunately, there is some major binding. The outer brake pad is way too tight, and the rotor will not spin freely. Something is not right.

A little troubleshooting found that the inner bearing seal doesn't fit right, causing the rotor to sit too far outward. To be honest, I have never seen this type of seal, so I don't know what to do. I removed the inner seal and the interference was gone; the rotor spins freely and correctly, and there is now room for the outer washer. I'll call the manufacturer tomorrow and get some help with this. I have confidence it will be a simple fix, since everything else fit very well. I'll paint the caliper and rotor nose with some primer and satin black paint later (no bright red calipers for me, thanks, I'll leave that to the kids).



Overall, I am very satisfied and optimistic with this disc brake conversion. I like the bearing upgrade. I look forward to great braking performance. Perhaps the instructions could have been more clear, and that's considering I think I know a lot about brakes. It is also a cool functional upgrade that doesn't announce itself. Nobody will detect this unless they go to great trouble to look under the car.



I feel for someone with less experience, and certainly less tool resources. This conversion might be tough for them. Just knowing to heat the 5/8 bolt with an acetylene torch, and having said torch at hand, would make the difference between just an extra step or a major stumbling block. Also, you need big sockets, which I have. Nothing else would really work.

I'll get an extra set of brake pads, and put them in the spares box I plan to carry in the trunk of the car. The rest of the brake parts are more modern by about 30 years, so sourcing them in the future will be easier as well. The conversion is also cost-effective. It would have cost about as much to have just done a rebuild to stock.
I am totally psyched about these new front disc brakes!

Crispy cat approves.