New brakes

[wetminkey]

Wrong. Rotors are not the wear surface.
I've been doing brakes for nearly fifty years. Rotors should be proper factory thickness, and pads should be as thick as possible.
Thin pads lead to chewed rotors,...
Vicks' should not sell oversized rotors, and no one should sell oversized, or undersized, pads.
I'm glad that I'm nearly DONE with any mechanical issues! I don't want to have to deal with parts and vendors anymore!
At this time, I find that most people do not have a good grasp of auto mechanics and I am ready to quit my hobby of restoring cars,...

[DieselSpider]

Wrong. Rotors are not the wear surface.
I've been doing brakes for nearly fifty years. Rotors should be proper factory thickness, and pads should be as thick as possible.
Thin pads lead to chewed rotors,...
Vicks' should not sell oversized rotors, and no one should sell oversized, or undersized, pads.
I'm glad that I'm nearly DONE with any mechanical issues! I don't want to have to deal with parts and vendors anymore!
At this time, I find that most people do not have a good grasp of auto mechanics and I am ready to quit my hobby of restoring cars,...

Over 50 years here and while the rotors should not be over sized you really need to measure them and if standard sized pads will work then your usually best off going with the KISS principle since it usually eliminates a lot of angst and grief.

I went with the locally available Centric C-Tek Installation Ready Standard Brake Rotors for my Spider which were also a little thick however they were nicely machined brake ready and just under $10 each and the standard Wagner Pads fit just fine after removing the squeal pad. I now wish that I had purchased a few spare rotors at those prices. Raw rotors that you needed to machine were more expensive than the Centric C-Teks however thats probably because they are not as popular and around here mostly custom shops get them to modify themselves on the own brake lathes and mills.

You do have to go with the flow and step back from being a purist at times. I find most times on brake items that they are locally available at better prices than the internet and its easier to deal with fitment issues when you can belly up to the counter where you bought them to make an exchange so it only takes minutes to deal with instead of days or weeks. Many times with over thick pads its not the friction material but the steel backing plates that the pads are bonded to that are too thick or even the bonding agent itself so you may not get additional wear from them when they are too thick. I also try not to mix and match which stores I buy my pads and rotors from so there is no passing the buck either as to whether its his pads, their rotors or that other guys calipers.

Try dealing with the brakes on some Ford 20,000 lb chassis. Some have the calipers on the drive axle mounted to the front of the axle while others to the rear while others may have the left caliper on the front and right caliper on the rear of the axle or visa vie making it difficult to ensure you get the correct calipers. On the axles that have one caliper mounted to the front and the other to the rear you need two of the same calipers however some parts suppliers get confused as to whether you need two lefts or two rights and end up giving you the wrong ones for your application.

One thing I've learned most of all is to put frustration aside and not let these things get to you. No need to quit over some thing as minor in the big scheme of life as this.

[wetminkey]

Restoring vehicles - I've got too many vehicles already (see list, below), and my wife has made me swear it off, anyway. So, I'll still be finishing the ones I have, and driving them! It would be hard for me to quit,...I love it too much and have been doing it for too long.
Anyway. These crazy brakes,...
No problems NOW! Autozone ceramic pads were cheap, and 5 miles down the road,...they did have to order them, yesterday.
I'm doing rears at the moment (fronts to follow) and I was looking at the excess space available, once everything is in place, and before calipers are compressed,...Vick's 10.8mm rotors MAY have fit, but it would have been really tight on the driver's rear. I would think that standard thickness pads would drag a bit at first, but it's hard to tell by just looking.
Anyway, my rotors are exactly full thickness, true, and nicely surfaced. New calipers, pads, and hoses. And a new emergency brake cable - my old one looked terrible! It certainly could have been part of the brake system's problem,...
Bleeding time. Then on to the fronts,...
Sorry about being so upset yesterday. Grinding rotors makes me that way, I guess,...especially after I find out that I may not have had to do it,...!

[RRoller123]

I am confused by something. If rotors are not the wear surface, then how is it that they become too thin over time to resurface? It seems that pads and rotors both wear, with pads wearing at a higher rate?

[DieselSpider]

Restoring vehicles - I've got too many vehicles already (see list, below), and my wife has made me swear it off, anyway. So, I'll still be finishing the ones I have, and driving them! It would be hard for me to quit,...I love it too much and have been doing it for too long.
Anyway. These crazy brakes,...
No problems NOW! Autozone ceramic pads were cheap, and 5 miles down the road,...they did have to order them, yesterday.
I'm doing rears at the moment (fronts to follow) and I was looking at the excess space available, once everything is in place, and before calipers are compressed,...Vick's 10.8mm rotors MAY have fit, but it would have been really tight on the driver's rear. I would think that standard thickness pads would drag a bit at first, but it's hard to tell by just looking.
Anyway, my rotors are exactly full thickness, true, and nicely surfaced. New calipers, pads, and hoses. And a new emergency brake cable - my old one looked terrible! It certainly could have been part of the brake system's problem,...
Bleeding time. Then on to the fronts,...
Sorry about being so upset yesterday. Grinding rotors makes me that way, I guess,...especially after I find out that I may not have had to do it,...!

Believe me I feel your pain and really hate it when I see someone going through this type of stuff.

Keep at it and eventually we shall overcome!

[dinghyguy]

Hey it could have been worse..... you could have had to rebuild the calipers like i am doing. I was using the nice reference document from the FAQs on Mira, but unfortunately that document does not address the cleanup and restoration of the self adjusting mechanism inside the caliper piston which it key to the proper operation of the handbrake. So I ended up taking it apart, cleaning it all up and reinstalling the piston. Not a big deal just some time. After that I can move the handbrake lever by hand and the piston moves correctly. Previously it was to stiff to move by hand.
On your new calipers can you operate the lever by hand without too much difficulty?
Oh to make yourself feel better paint your new calipers red, then tell everyone they are baby Brembo's.

cheers
dinghyguy

[18Fiatsandcounting]

I was using the nice reference document from the FAQs on Mira, but unfortunately that document does not address the cleanup and restoration of the self adjusting mechanism inside the caliper piston which it key to the proper operation of the handbrake.

Dinghyguy, there is a trick to getting this right, and I was able to do it many years ago but seem to have forgotten. It has something to do with the worm screw in the rear caliper piston, the screw that fits into a "nut" fixed inside the piston, and apparently this nut slowly rotates down the worm screw as the pads wear out (and thus the piston moves out), allowing the handbrake cam to always be in the right position. The screw is fixed in place and pushed on by the handbrake cam lever, and it's the proper turning of this nut that makes it all work.

When I got it right many years ago, the handbrake was amazing as it would lock the rear wheels if you yanked up on the lever while driving, and the hydraulic rear brakes functioned otherwise exactly as they should. If anyone has any tips to setting this up correctly, please share.

-Bryan

[dinghyguy]

Bryan,
The lever from the brake cable acts on the threaded rod bit shown inserted in the photo below


the threaded rod bit projects into the caliper cylinder location. the threaded rod bit is shown below.
Note that the belleville washers orientation is critical. They provide the spring force to pull the piston off the brake pad when the handbrake is released.


The piston has the self adjusting mechanism inside. The parts are shown below.


The nut and spring fit into the piston, there is a hole for the end of the spring.
The roller bearing sits on top of the nut
The keeper plate sits on the bearing
The circlip holds in all in.

With the threaded rod bit installed in the caliper, the piston is screwed down onto the threaded rod and mentioned in the manuals

In operation the nut (and piston) can rotate down the threaded rod performing the self adjusting function for the handbrake system as the brake pads wear. The Belleville washers always retract the piston the same amount regardless of piston location. Thus when (not if) the nut/spring/bearing assembly gets gummed up the piston will not self adjust properly and your handbrake will either not grip well because the pads wear and the piston cant follow, or the system will not release properly and the brake may stick.
as i said, when properly clean and free i am able to mek the piston move freely using the handbrake cable lever and the piston threaded on easily as well.
I strongly suggest everyone should pull the caliper off, remove the pistons and confirm his mechanism is working properly. The rebuild kit is cheap and the improvement will be noticeable.

Sorry Todd for highjacking your thread. I bet if you take your old calipers apart the adjuster bit in the pistons is gunked up! If you do check you can take decent photos......

cheers
dinghyguy

[DieselSpider]

Deleted contents of duplicated post

[DieselSpider]

...the threaded rod bit projects into the caliper cylinder location. the threaded rod bit is shown below.
Note that the belleville washers orientation is critical. They provide the spring force to pull the piston off the brake pad when the handbrake is released.
...

When dealing with some rear calipers for the 124 which I was told were bought new and had never been disassembled I found only 4 belvilles and they were not in the correct orientation against the backing plate so the parking brake has never worked correctly since instead of this ()()(| they had (())|. With the belevilles doubled like that they provide twice as much resistance making it basically impossible to set the parking brake plus did not fully activate the spiral clutch spring adjuster inside the back of the piston.

So when doing the rears you should at least check that the tension, when you try to manually activate the parking brake levers on each caliper, is the same on both sides and if their not take a look to ensure that the belville stack is correct on both of them. New, used or rebuilt you could run into this since not everyone involved in even assembling new calipers may have much if any experience with the style of caliper used on our cars.

Also if the spring clutch is not installed or working correctly inside the piston you may never get the piston to fully retract since it can just start spinning on the adjuster clutch before the piston has bottomed out.

[wetminkey]

Naw, dinghyguy,...this is all brake related! It goes perfectly with this post - it's all about new brakes.
The calipers I just removed are the factory set, for sure. "Fiat" all over them. And they're filthy.
I suppose that the rotors are 1979, also,...two terribly scored (not functional), one ugly (perhaps functional), one in reasonable shape,...
The emergency brake cable looks like in was involved in some sort of accident,...just kidding. It's U.G.L.Y.!
With everything cleaned up, and all the new parts, my Spider's brake system is a real thing of beauty now!
Seems like my wife, and I, have it bled nicely, too.
I'm going to wait for new wheel alignment dowels before I bolt on the front wheels and get the car down off the jacks. I've found one with a terribly gummed up hex, and I do not want to reinstall it for any reason. The rest are OK, but I'm going to replace them anyway,...I'll save my old good ones, since all I could find were refurbished used ones for replacements.

I should be done with brakes. But to sum it all up: do not hesitate to measure and question the thicknesses of everything,...NO MATTER WHAT IS CLAIMED, even on the box that it comes in.
Fiat Shop Manual says nominal brake rotor thickness is 0.3917 in. - 0.3995 in (9.95 mm - 10.15 mm) and my rotors came 10.8 mm,...I understand they can fit with stock pads. Probably should have a light grind to create a nice friction surface for the new pads, since they come smooth,...
Rotors are throw-aways at 0.354 in., which is 9 mm. They're not intended to wear very much,...!
Rear pads should be no thicker than 0.4 in. Front pads are thicker, of course,...about 0.75 in.,...that's measuring the thickness of the entire pad and plate. They're trash when the friction material is at 0.0787 in. (2 mm).
And, finally, never hesitate to replace the rubber caliper hoses (and the emergency brake cable, especially in this sort of system).
Oh,...and remember to test the brakes in the drive, before testing it all on the highway!
I think all of the information is here,...I hope it can act as a searchable resource for brake information.
Happy Motoring! Todd.

[18Fiatsandcounting]

Thanks, Dinghyguy, and my recollection is exactly as you described. Yes, many people (including brake rebuilders) take the easier route and "nest" the Belleville washers together, rather than ()()(| as you describe (that last vertical slash being the flat washer than rests in the recess of the caliper). It's a bit of a pain to do it the right way as the only tools I have for this are a vise, c-clamps, vise-grips, etc. But, I did orient everything properly and cleaned up the nut/spring, bearing, keeper plate and circlip.

For my '71 that I'm currently going over extensively, I'll have a test of your method (which I believe to be entirely correct) in a few weeks. All the brakes have been redone, with the exception of the passenger front caliper, and I'm currently in the process of rebuilding the upper and lower A-arms for that wheel. Of course, along the way I got distracted by rebuilding the idler box, steering box (needed new seals), a new master cylinder, and removal of the brake booster for a good cleaning. So, I have a lot going on simultaneously.

Long story short: I should finish the passenger front caliper pretty soon and I'll be able to test the whole system.

And also thanks to Wetminkey for allowing this side trip on his thread!

-Bryan

[wetminkey]

You bet! It's a thread about NEW BRAKES. Not specifically about MY new brakes (who cares,...), but about Fiat Spider new brakes!
That's my idea behind 'pictorials' and that's why I like to put these kind of threads together. It's about new brakes for the Fiat Spider. My hope is to provide enough information so that other owners can avoid the 'hit and miss', or 'trial and error', method of automotive projects. If they search, they'll find the information on this forum,...
I'm not sure that this is applicable to all years, but it certainly covers a significant number of the Spider brake systems. Useful stuff,...
And you guys have provided info that I would not have,...about rebuilding the rear calipers. More cool stuff,...

[MattVAS]

I got wetminkey's approval to post this first as I am NOT trying to start ANY FIGHTS!!!

I'm not picking sides on ANY points of interest about what does what and where. I just took the time to do a bit of research and see what everyone is making and how.

I picked three brands to balance the size and see if anyone is over doing it. Here are my results.

Vick Autosports Carries Forma Pads and InterCar Rotors
Our pads are from Forma of Italy and our rotors are from Intercar of Italy
*Front Pads - 17mm (http://forma2004.it/cerca.php search for pad # WP8015) (TUV Certified)
*Rotors - 10.8mm (https://www.intercar.org/catalogo/ccar_eng.php) (TUV Certified)


Below parts are companies that we don't carry but were used for comparison.
Now for comparison to others
Trusting Brake Company (they are a division of Metelli Spa of Italy) (NOT TUV Certified)
http://www.metellispa.com/files/catalog ... s_2017.pdf
pretty sure the Fiat 124 is on page 244
*Front Pads - 17.5mm
*Rotors - 11.0mm

Centric Brakes
https://www.apcautotech.com/automotive- ... ng-systems
*Front Pads - 17mm
*Rotors - 10.9mm

We do carry this pad. I measured is to get an extra stat on pad thickness.
Ferodo Pads
Pad - 17mm

I did look at other manufacturers. The key was that I found 17mm was the standard thickness for the Front Brake Pad. As for Rotors I would say they vary a lot lot from manufacturer to manufacturer BUT only in the TINY range of 10.8-11mm

I hope these numbers help.

[wetminkey]

Thanks for posting the info that you collected, Matt! I find the details to be quite interesting,...
The set of ceramic pads that I bought measured: fronts: 0.75 inches is 19.05 mm, rears: 0.4 inches is 10.16 mm. I'm measuring the entire pad thickness,...pad and backing plate.
Wow,...
I know for a fact that these dimensions fit just fine with 0.3995 inch (or 10.15 mm) discs,...even in the rear, which seems to be tighter.
From my observations, I'd guess that you could EASILY fit a wider rotor in the front, but the space that I had available in the rear pads (with new calipers, bottomed out), might not have accommodated the 10.8 mm disc without dragging. I do not know, and will defer to everyone else who has done this already "without problems".
Cool discussion,...!
Todd.