How do I fix this rear disc brake problem?
I'm having some braking problems and then I discovered this (I did not build this car).
It looks like the calipers are oriented correctly, but the parking brake cables on the right rear are working "backwards" and will never keep the pads adjusted. I believe these are Caddy calipers, but I'm not certain (diff is a Chevy Nova 10-bolt). It seems that I just need a set of parking cable brackets like the ones on the left rear, but I'm not sure what to get.
I disassembled both sides.
While both calipers are marked "R", the parking brake brackets are handed "L" and "R".
So what I need is an additional set of "R" brackets.
But where since I don't know what car the calipers came from?
Can anybody identify them so I can source them?
So somebody else found this little problem.
These are Seville rear brakes.
The cables are normally run over the rear end and pull the opposite way from the way we like to see them on our streetrods.
So what to do??
First do a search for Seville rear brake problems on the internet. Eventually you will get some information on how these work. This will give you the information you will need to work with these brakes. I'd help out but I lost the URLs in a computer crash a while ago.
Take a very close look at what happens when you move the cable arm. You may have two of the same side. There is a left and a right.
I mounted mine so the cables pull from the front, sort of like you have done. Unfortunately this puts them on the wrong side of the rear end.
They don't tell you this in the instructions. BTW, no instructions came with my kit.
I had to do this the hard way.
I took them apart and reversed the gut pieces, left went to the right, right went to the left. I also had to make a minor modification to the arms as a result. I think I reversed the arms too. There was a minor mod done to the brackets too. This made it so when the arms are pulled forward the E brake applies. It's been 10 years so memory is a little short.
You also should get a couple of rebuild kits as you will most likely damage at least one of the o rings. Oh yes these kits can be a bit hard to get.
You will also need a 10 psi residual valve on the rear brakes. These are the only disc brakes requiring this. There is a GM TSB regarding this. If you don't do this you will have low pedal. The reason for this is that the parking brake retracts the piston about .050 instead of .010 so you need to have some residual pressure to keep the pads near the rotor.
When you bleed these it very important to make sure all the air is out of the system. As I recall the last time I serviced mine I removed the caliper and rotated it so the bleeder was straight up. I think one of the GM TSB says to wiggle the caliper around to make the final air bubbles come out. They get caught in the ratchet mechanism. Pressure bleeding will not help. Actually a true vacuum bleeding is the best but it is very hard to do. When I repaired a leak in one of these I bled it on the bench first then again when I installed it on the car. This worked the best. I actually have very high pedal now.
It can be difficult to get the adjustment correctly. If you dig around on the internet you find various methods of doing this. Most say that you need to snap the lever about 30-50 times to get the one way clutch inside to ratchet to the minimum position. It is a real pain. If you are really, really careful you can remove the arm and turn the shaft untill you can just get the arm back on. This will usually cost you and o-ring. BTW I used a small vise grip on the arm when snapping. It makes it easier.
Plan on an all day project if everything works the first time.
Caddy mechanics cussed these everyday.
They actually do work once you get them set up.
Finally you MUST activate the E brake every time to park the car. If you don't the ratchet mechanism will freeze up and the E brake will not work. The pads will wear down and the pedal will get lower and lower as the adjustment is gone.
Don't forget to release the e brake either. The rear brakes will get very hot and the pads will wear down. I've done this at least a dozen times haha
That's it in a nut sack.
From what I read here and what I saw when I took the the parking brake copmponents off yesterday, I have two right-hand Seville rear calipers but a left- and right-hand set of parking brake brackets.
So I need to obtain a set of right-hand brackets to make both cables work correctly and then adjust the brakes, then remember to set the parking brake every time I park the car.
You need both left and right hand calipers as the ratchet mechanisim is based on a one way clutch. In other words one works going CW the other workd going CCW.
Also the matching brackets.
If it stops raining I'll back the car out of the trailer try and get a couple pictures of how mine is mounted and the mods to the arms and bkts. These are just a small welded piece on each.
I also looked on Speedway and they have some instructions on the bleeding and residual valve issue. They say to remove the calipers and bleed them by pointing the bleeders vertical. You still need to tap on the caliper with a small hammer to shake the final bubbles out of the ratchets.
I looked at a left-hand caliper. It can only be mounted on the axle brackets so that the bleeder valve is pointed down, so that won't fix the problem. That's why there are two right-hand calipers used in this application.
I am all too familiar with these bad boys.
(That actually comes up as the first result for Googling "seville parking brake calipers hotrod".)
I was working on them just before health and family issues forced me to set this project aside two years ago.
NAPA and the Caddy dealer are no help. That means Pick-A-Part or a place like http://www.cadillacsonly.com/.
Or I suppose I can cut, bend and re-weld the left-hand bracket; the lever arm looks like it will work just being flipped over.
Can I find the brackets on any other GM vehicle of the era? I've read that these are 79-85 Seville and some Eldorados. With my luck, Pick-A-Part will no have any . . .
P.I.T.A. is what they really are.
Ok I have a couple of pictures. I had to take these blind as it was raining and I had to slither under the car in the trailer. I couldn't see the view finder so I just shot with macro and flash.
The first was the left side without flash
the second was the left with flash
the third was the left side
the fourth was the right side
If you look very carefully you can see the R and the L in the castings
My calipers are on the front side of the rear end so I guess that is why I had to reverse the guts.
If you look close you can see the small tabs I welded on to the arms.
I think I also either redrilled a hole or ground somethign out of the brackets.
It's been at least 10 years since I did this and I have replaced pads twice and bled them a few times due to leaks.
This is a weld on kit from Speedway. I used a Lokar floor mount e-brake handle. You have to get the adjustment just right for it to really work. My car idles about 900 rpm and pulls against the brakes. These did hold for the safety inspection however.
I was just at an event tonight and I think I may add Hawk pads later this summer (if we have one). I'd really like the brakes to work harder.
I would suggest you cut off your current stuff and get the Speedway kit. I like the weld on one but there is a bolt on one too.
Go thru the disassembly process as described in the above links. observe the difference in operation left to right. You probably don't have to take the pistons/clutch apart unless you have rust in the caliper. If that is the case I'd just replace them...about $100 each.
Make sure you have the correct hats too.
Mine mount at the front AND the rear which is why I use two RH calipers in my application. One caliper works correctly, the other _would_ work correctly if it just had the brackets for a RH caliper.
I'll keep looking. The guy from Caddliacs Only wants $350 for a full set with brackets which is too much just to get two RH brackets. Looks like I'll be spending time at Pick-and-Pay . Or how hard could it be to fab a RH bracket?
It shouldn't be too difficult to make a special bracket. I'd try and use a piece of square to rectangle tubing about 1/8 wall. cut it off at some angle and drill the holes as required. You may have to make a couple attempts to get it right.
Otherwise cut up some flat stock and weld it all together. It's lots easier to do this with a TIG welder than a wire welder.
I wound up fabbing a bracket and the only modification I had to make was shortening the spring (it would bind and not allow the caliper to compress fully.
Seems to work OK for now.
Great. I hope it all works for you. Mine still are marginal at best for holding the car with the e-brake. You absolutely must cycle it every time you run the car or they will not adjust. My biggest problem is that I forget the e-brake is on and drive off untill I notice it. It really needs a "brake" light.
As far as the braking goes this system with Granada front rotors is reasonable for my car. The car is only 2800 pounds rolling so it stops right with most of the modern day performance cars. My winter project is to install some Hawk high friction pads and a double 7" booster. This will allow the brakes to match my "go" power.
If your car is heavier I'd suggest you do this too. actually if you can use the 8" booster it will be even better. I don't have room in my car.
I'm using a double 7"; also no room for an 8" on tmy 3400-pound car.
I've used the Hawk high friction pads and, while they do work better than the stock pads, I get a lot of brake dust.
|All times are GMT -6. The time now is 06:58 AM.|
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.