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Tech/Performance/Info >> Brakes >> Does anybody have a working parking brake? How?
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Message started by Gary Cook L82-1977 on Dec 3rd, 2012 at 7:33am

Title: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Dec 3rd, 2012 at 7:33am
It's been a long time since I posted.  Some of the old-timers are still here and might remember the guy who took his C3 to Spain.  That's me.  I was on here regularly around 2005/2006 when I restored my 77 and moved to the Canary Islands.  Well..  It's been mainly a hanger queen for one reason or another.  Mostly related to travel and time to do anything since I moved. 

Now it's time to take it through the Spanish vehicle inspection process (ITV).  I've worked out all the paperwork so I don't have to modify it to euro standards, bringing it in as a "returning resident" with my wife.  But I've got a serious problem with the parking brake.  It just does not hold.  I've done absolutely everything with almost zero improvement:

Everything is new.  Some parts 2 or more times.

1.  New rotors.  Old ones were fine though.
2.  New parking brake shoes.  I've probably tried a dozen sets.  Some from Corvette parts vendors such as Corvette America.  Tried riveted.  Tried bonded.  Destroyed a few.  Tried Delco.  Tried Raybestos.  Raybestos is on it now. 
3.  All new hardware..  Springs, etc.  Two sets.
4.  New stainless cable..  Twice.  Tried a second one in case the cable was stretching under pressure.
5.  New parking brake lever.  Not related to the problem but it was replaced for cosmetic reasons.

Not one part has been overlooked.  The backing plates are the only original pieces and they look fine.

So how can I make this hold?  It seems to work pretty good in reverse.  You can yank on the handle and it will stop the car pretty quickly.  Not sure if it will lock the wheel.  Forward, it takes forever to stop the vehicle.  I don't think it will pass inspection.

I've even tried tightening the adjuster until the brakes are rubbing the drum.  That helps a little but I don't think it's good enough. 

I tried to grind a set of shoes to match the shape of the drum.  No success. 

It's strange to me that it works pretty good in reverse but not forward.

I really need a solution.  Tired of driving it around the neighborhood only!

Thanks.  GC

Title: Re: Does anybody have a working parking brake? How?
Post by Knotacare on Dec 3rd, 2012 at 8:13am
Welcome back Gary, I've had the same problem. they hold in rev but not to good forward. It just a crappy design. You can try my conversion & make it work with a switch. The linear actuator holds very well & pulls it tighter than the hand break & you end up with more room in the cabin.
Alan [smiley=beer.gif]
http://108.60.3.46/cgi-bin/yabb2/YaBB.pl?num=1238682246

Title: Re: Does anybody have a working parking brake? How?
Post by Binnie on Dec 3rd, 2012 at 8:40am
When I had my new '77, the emergency brakes would not hold the car going forward and that was new from the factory.  The brake will hold the car provided there is no power to the wheels.  I have no clue how GM got away with using that design for so many years.

Title: Re: Does anybody have a working parking brake? How?
Post by TX 73 stock on Dec 3rd, 2012 at 9:05am
I tinkered with mine to see if I could lock the rear wheels and it never came close. could barely lock them up in the rain. glad I'm reading this. I'll take fixing it off the list.

Good Luck Gary,

Charlie

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Dec 3rd, 2012 at 9:19am
Thanks guys.  Glad to be back.  This is really bad.  I didn't worry about it in California.  There were no inspections.  Here you have to go through it every year.  I had no idea they would put it on some rollers to test it.  I was hoping for a magic cure.  Even something that lasts 5 minutes.  Long enough to do the test.  Seems like I saw something about coating to increase friction.  I need to research that again. 

Alan..  Your fix is cool.  The new large Opel (and Buick in the USA) has an electric switch PB.  Here I'm afraid the inspectors would question it since it doesn't look at all stock.  It might work for the test but fail the visual.  The first time through with an import is pretty thorough.  What would be a good fix is a cable operated disc brake.  Probably would cost an arm and leg to buy and install.

Binnie.  I agree.  What a piece of garbage design! 

It's really hard to do any major work here.  No skills and no parts.  I've got the only C3 on the island.  Never seen a C1 or C2 here.  There was a couple of C4's but they are gone.  Same for the C6. 

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Dec 3rd, 2012 at 9:27am
Here's what I was thinking about:

http://www.carbinite.com/applications/steel.html

Textured to increase friction.  I would have a set coated and probably use them once a year to pass inspection!

UPDATE:  I just contacted the company.  I'll keep you updated.

Title: Re: Does anybody have a working parking brake? How?
Post by blue 77 on Dec 3rd, 2012 at 9:58am

Gary Cook L82-1977 wrote on Dec 3rd, 2012 at 9:19am:
Binnie.  I agree.  What a piece of garbage design!

Bought mine new.  Fresh from the dealer's lot the parking brake did not hold if you applied power.  Very bad GM design.  The best you can hope is that it will hold the car from rolling if in neutral, but it will not hold against power. ::)

Dale

Title: Re: Does anybody have a working parking brake? How?
Post by Knotacare on Dec 3rd, 2012 at 10:50am
In the old days when I used to change lots of drum breaks I would take the breaks shoes & put them against the drum then file it until it fit perfect. Made a Hugh difference.. You might want to make sure they fit real snug. I know on the blue vette they hold forward & in reverse now. You could also rig a switch on the break handle to engage & disengage the er breaks...then it wiould look real ;)
Alan [smiley=beer.gif]

Title: Re: Does anybody have a working parking brake? How?
Post by TX 73 stock on Dec 3rd, 2012 at 10:52am
I'd try roughing up the drum and make sure the pads are clean. just might be enough to hold it real good for a minute.

Charlie

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Dec 3rd, 2012 at 11:45am
I spent all day fitting a set of parking brake shoes to the new drums.  Didn't help plus ended up cracking the shoes at the rivets after a couple of parking brake stops.  I switched to the Raybestos and Delco bonded shoes.  At least they aren't cracking under abuse. 

Tried roughing up the pads too.  Zero results. 

Title: Re: Does anybody have a working parking brake? How?
Post by Maximus79 on Dec 3rd, 2012 at 7:38pm
Welcome back,Gary!!  [smiley=beer.gif] [smiley=vrolijk_26.gif] ...Might be dumb on my part,but I rarely,if ever,use my parking brake in my 79.Not sure,but doubt the design is any different than on the 77 I had.There are no hills in my area I would park on,without a curb to turn my wheeels into.But now that this has come up on the forum,I'm going to go out & test them. Today I just paid over $600 having the brakes repaired on my 99 Mit. Galant.I started feeling some 'vibration',& some resistance during acceleration.Turns out the caliper on the right front had siezed up enough to overheat the rotor enough that it cracked.And these were slotted & cross drilled upgrades I put one a couple yrs ago.Im financially strapped & moving out of the house,so they are now back to stock style.Im thinking my mileage should improve some now.  ::) ;)

Title: Re: Does anybody have a working parking brake? How?
Post by olddiver on Dec 3rd, 2012 at 9:47pm
GC
This might be a waste of time but I've been looking into the
All-Pro 4x4 companys All-Pro transfer case mounted Disc parking brake system. Runs about $375.00 with all the parts. If you can make it work, let us know. If its a waste :-/ please don't tell anyone it was suggested by me. Thanks
....Mark

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Dec 4th, 2012 at 12:19am
Mark.  If I were still in California, I might give it a try but here in the land of Renaults, no way!   :)  If I get in trouble there is no way out of the mess.

Maximus..  Thanks.  Good to be back and have the '77 back at the top of my priority list after so many years.  This didn't go exactly as planned.  I thought I might be semi-retired over here.  I'm working and traveling more than ever!  That's a good thing in these times.  The hills around here are like San Francisco.  If you aren't going up, you are going down.  A parking brake is a necessity unless you only hang out at the beach! 


Title: Re: Does anybody have a working parking brake? How?
Post by Maximus79 on Dec 4th, 2012 at 2:12am
I did live in Espana about 3 yrs,but never made it to the Canary Islands.Would love that weather rite about now! :-/

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Dec 4th, 2012 at 7:35am
It has been raining here like Seattle for almost 2 months.  We went through this 2 years ago too.  We painted the house and before all the paint dried, it poured rain for weeks.  Washed off all the paint on a wall!  But it's nice most of the time.  Similar to S. California at times.  We have a lot of micro-climates on our island because of the tall mountain and volcano.  We're on the wet side when it rains. 

So I'm collecting info to fix this brake when the weather clears. :) 


Title: Re: Does anybody have a working parking brake? How?
Post by Artsvettes on Dec 4th, 2012 at 10:05am
Back in the day a local junkyard sold brakes shoes new drums and resurfaced old ones. When he finished resurface he had a machine that he put the shoes on to surface match the drums then champher the ends of the shoes to break down the square edge on the shoe. I think this had to do with quick seating of shoe to drum. But I also think it reduced the chance of cracking. I have seen this more times than not on corvette p/b shoes, especially riveted shoes. But that still doesn't solve the problem of a piss poor design by the general.
  In jersey I remember guys tighten up the adjustment and hoped for the best. The better way would have been to use a caliper that has a built in park brake.But the engineers blew the budget when they designed the IRS and the brake system failed horribly because of it.  The BOP and cadillac used them n the eighties, and late model Mustang uses that type system. Now that these cars see little use and most don't see any inspections. It wouldn't be very cost effective to try and come up with caliper/ pb system. Unless you came up with one with over the counter parts ::)  ...........jack   

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Dec 5th, 2012 at 7:43am
The people from Carbinite returned my message.  This harder than steel coating will increase friction between the drum and shoes.  They said they've done something like this before for the military. 

I'm shipping two new rotors to them so they can apply the coating to the inside drum.  Cost is about $7.00/square inch.  He said he would turn it around in a day but I told him to take his time.  Not a rush.  I've waited 6 years already!

Keeping my fingers crossed.  This could be the ultimate parking brake fix.  With all the back and forth shipping plus holiday delays I probably won't get an opportunity to install them until the end of the month.

Stay tuned for updates. 

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Dec 5th, 2012 at 8:42am
Jack.

I tried the adjustment.  It is cranked to the max.  It is so tight now you can feel the drag when you move the car! 

If you take a new brake shoe and check how it fits in a new rotor, you'll see a huge gap.  I don't see how it could ever wear into place.  I've tried all kinds of shoes and they fit the same.  I thought it was the rotor possibly being ground too much.  The new ones are the same.  I did the grinding trick.  I used to do that back in my mechanic days when just about every car had drum brakes.   

Just a piss poor design.  I'm hoping to compensate for it with increased friction.

Title: Re: Does anybody have a working parking brake? How?
Post by blue 77 on Dec 5th, 2012 at 11:56am

Gary Cook L82-1977 wrote on Dec 5th, 2012 at 8:42am:
Just a piss poor design.

Gary, I think you've nailed the problem.

Dale

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Dec 5th, 2012 at 12:05pm
Isn't it amazing that this problem existed for so long?   :o

Don't you think that some executive from GM would notice the problem while driving their new Corvette company car?  At least once between 1965 and 1982?  Or that the guys driving them off the assembly line would say something?  You've got to wonder what would have been considered a failure.  Things were certainly different back then.

Title: Re: Does anybody have a working parking brake? How?
Post by blue 77 on Dec 5th, 2012 at 12:35pm
Probably thought "What the H*LL",  why worry about it if consumers keep buying them and not complaining.  I know when I noticed mine and mentioned it to the dealer, they said "that's just the way it is."

Dale

Title: Re: Does anybody have a working parking brake? How?
Post by TX 73 stock on Dec 5th, 2012 at 1:06pm
yeah, they were not made so you can grab it and do a 180. not even in the rain which is a lot of fun. just supposed to keep the car from rolling from a dead stop. however, if you have it parked on a hill and you get bumped, you'd think it would at least slow it back down. is it really that bad?

Charlie

Title: Re: Does anybody have a working parking brake? How?
Post by olddiver on Dec 27th, 2012 at 2:04pm
I was just thinking ( got a headache  >:( ) has anyone tried one of those line- lock systems? Just throwing that out there.
....Mark

Title: Re: Does anybody have a working parking brake? How?
Post by Knotacare on Dec 27th, 2012 at 2:37pm
Line lock would work on the frt or rear breaks, but I don't think it would be a good idea to keep pressure on your break lines for a long period. It's a bad idea & the only thing that seems to work is applying more pull than you can achieve on the hand break. This is why the linear  actuator works, it pulls 200lbs of pressure.
Alan [smiley=beer.gif]

Title: Re: Does anybody have a working parking brake? How?
Post by olddiver on Dec 27th, 2012 at 4:47pm
Thanks Alan,
Didn't know if it would work or not. It will be awhile :-[ before its back on the road and I'm sure I'll have to deal with this. Just trying to prepare. Thanks for the input!
....Mark

Title: Re: Does anybody have a working parking brake? How?
Post by TX 73 stock on Dec 28th, 2012 at 6:04am
I haven't looked into this but I wonder if there's enough room to install an offset pully that could increase the handle pull power. sure you would loose some range but it seems there's plenty of handle movement to account for increased leverage.

Charlie

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Jan 3rd, 2013 at 6:59am
Charlie.. 

I don't think a larger or offset pulley would help.  I've cranked down the shoes to where they rub and tightened the cables to the max.  That leaves at least 1/2 the travel in the handle when pulled to the max.  Also on mine I've replaced the 4 speed with a 5 speed.  It's pretty close to the pulley.

Still waiting on my updated rotors.  They should be about finished with the work.

P.S.  Yes.  The parking brake is that bad.  Mine won't hold on a 10 degree or more incline.  It also won't stop the car moving forward unless you have a 1/4 mile!  Funny thing is that it does hold pretty good in reverse.  I'd say it is completely acceptable.  Does anybody else see that?  That leads to why would it be better in reverse than forward?  Same size shoe front/rear.  Mechanism is basically center pull.


Title: Re: Does anybody have a working parking brake? How?
Post by TX 73 stock on Jan 3rd, 2013 at 8:43am
I've owned my fair share of auto's and standards and the rule of thumb I learned is if you have a standard then you always set the e-brake. I think it works better in reverse because of weight transfer. same rule applies to power pulling. for a front wheel drive, you want to pull from the front in reverse and for rear wheel, you want to pull from the rear in forward gear.

Charlie

Title: Re: Does anybody have a working parking brake? How?
Post by blue 77 on Jan 4th, 2013 at 11:48am

Gary Cook L82-1977 wrote on Jan 3rd, 2013 at 6:59am:
Funny thing is that it does hold pretty good in reverse.  I'd say it is completely acceptable.  Does anybody else see that?

Been so long since I actually used mine I can't remember for sure, :-[ but I do think it held better in reverse also. :-/  Know it didn't hold in any forward gear. ;)

Dale

Title: Re: Does anybody have a working parking brake? How?
Post by VETTE 1977 on Jan 5th, 2013 at 5:22am
I'm in the same boat Dale. Don't know if it even works now but when it did, it was better in reverse than in any forward gear. My trick at the Corvette shows when they checked the operation of the "E" brake was to put it in reverse and let the clutch out very slowly just to lug the engine down. Up here anyway they wanted it to be done in a forward gear. It worked every time.

Dave

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Apr 16th, 2013 at 12:41am
It's been a while.  Finally got the modified rotors back after a long delay.  They weren't the fastest at getting the work done.  Note to self:  Never tell anybody to take their time because you aren't in a rush.  On the upside he didn't charge much for the work.  The parts look good.  The rough surface is about like 200 grit sand paper. 

:'(  It didn't work, at least for forward braking.  In reverse it will lock the wheels.  If you apply the brake and try to backup it will not move.  Reverse hold is incredible.  So that improved.  Front is non-existent!  It won't hold the car in neutral on a 5 - 10 degree slope.  That's bad and it's not right. 

:-?  I am out of ideas.  Why is reverse hold perfect and forward zero?  It's almost like the front shoe (or rear) isn't being equally leveraged against the drum.  The mechanics of how that is done is simple enough and the parts are new so I just don't get it.

Every part from the brake handle to the rotors has been replaced at least once except the backing plate which looks ok and allows the shoes to move freely.  I've replaced it all and tried it all.  New handle.  5 sets of shoes.  3 different sets of rotors.  I've tried to shape the shoe to the rotor.  I've tried bonded and riveted shoes.  I've tried generic shoes and brand shoes.  New brake cables twice.  Springs and the rest of the hardware 2 times :-X.  Actuators.  I've tried loose adjust.  I've tried over adjusting to the point they are dragging.  There's no forward and backward ways of installing the shoes.  I've installed hundreds of drum brakes shoes back in the days.  I know old drum brake cars have a "short shoe to the front rule" but all the brake shoes have been the same here.

I don't know if this ever worked, before or after I started the restoration.  I bought the car and immediately tore it apart.  Things like parking brakes didn't really matter since the brakes and suspension were a mess.  I sure wish I had resolved this in California before shipping it to this place.  I'm at the point of ordering two complete trailing arm assemblies with the brakes and rotors already installed and adjusted.  I sort of hesitate at spending another 2000.00.  That's my last option.  I know more about this car than anybody on the island.  Not exactly an easy transition from a Renault Express to a Corvette as a mechanic.

So does anybody have the answer that will make me slap myself on the head and go damn I wish I'd thought of that before I spent a $2000+ trying to fix it!  :)

Title: Re: Does anybody have a working parking brake? How?
Post by Binnie on Apr 16th, 2013 at 4:43am
Gary, I think if you discover a fix for the parking brake problem you need to patent it.  As I already mentioned before, even when I drove my new '77 off the dealer lot, the parking brake would not hold in a forward gear.  I think any engineer looking at the design today would argue that it is seriously flawed due to shoe diameter, surface area and insufficient leverage dynamics. I really do not think there is anything you can do to the original setup that will result in an effective solution.

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Apr 16th, 2013 at 4:48am
Binnie,

Is yours so bad that one person could push the car forward on a flat driveway with it applied?  Mine is. 

I wish I could find a bolt on parking disc brake setup.  I could have had one custom made before moving.  Now it's too late. 

Title: Re: Does anybody have a working parking brake? How?
Post by Binnie on Apr 16th, 2013 at 5:04am
I have a steep driveway.  The hand brake will hold it in neutral from going backwards but it will not hold it in neutral going forward.  I agree the only solution is to have one fabricated using a brake of some type on the end of the transmission or on the disks themselves.  I think the reason that no-one ever developed an after market solution is because there would be so little demand for them.  In most jurisdictions these cars because of their age fall into the category where it is not necessary to have them inspected.

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Apr 16th, 2013 at 5:56am
The reverse holding is what baffles me.  It works perfectly.  Others have said the same. 

I'm going over some posts on other forums.  I found a reference to a worn pivot point.  I'll check that out this weekend.  Some refer to arcing the shoes.  I've done that.  The new coating I had applied to the inside surface does that automatically too! 


P.S.  I spent a few more minutes reading the article.  The worn pivot point I found on another forum (corvette action center) sounds like it could be exactly the problem.  Not enough leverage to move the shoes.  It matches what I see with my cable.  With new rotors and new brake shoes, it is still at the maximum when adjusted.  I thought it might have been the new cable so I replaced it a second time.  There's a simple test fix associated with it.

Title: Re: Does anybody have a working parking brake? How?
Post by Artsvettes on Apr 16th, 2013 at 12:07pm
  I think you have a better chance of drilling a hole through the floor, and drive a stake in the ground to stop the car from rolling. Than to get the original park brake to work. :o
I know this doesn't help but I had to say it........jack

Title: Re: Does anybody have a working parking brake? How?
Post by Binnie on Apr 16th, 2013 at 12:36pm

Artsvettes wrote on Apr 16th, 2013 at 12:07pm:
  I think you have a better chance of drilling a hole through the floor, and drive a stake in the ground to stop the car from rolling. Than to get the original park brake to work. :o
I know this doesn't help but I had to say it........jack


And Gary, that was coming from a guy that worked for GM  :)

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Apr 16th, 2013 at 12:49pm
I hear you.  That's pretty much everybody's opinion including mine.  I'm giving it one more try this weekend.  My patience is gone and my body can't take too many more parking brake reassembly job!  What a pain in the behind. 

If I could just get the Spanish inspectors to accept a stake in the ground, I'd be all set.  But those rollers that test it have no slot for a stake.   ;D

Title: Re: Does anybody have a working parking brake? How?
Post by Artsvettes on Apr 16th, 2013 at 2:25pm
My 99 blazer park brake was similar to the corvette except it was a one piece shoe that expanded in the rotor, and it worked very well.. In 99 we built a prototype right hand drive to export to Japan. The right side foot well was a lot smaller to accomodate a foot activated park brake. So we went with a hand activated park brake. Guess what? It wouldn't hold for squat. But that didn't stop the General from giving it the go ahead and bought off on it.
So history does repeat itself..............jack

Title: Re: Does anybody have a working parking brake? How?
Post by Maximus79 on Apr 16th, 2013 at 9:23pm
Has anyone here ever tried a line lock,& is that even feasable? I dont know much about them

Title: Re: Does anybody have a working parking brake? How?
Post by Gary Cook L82-1977 on Apr 17th, 2013 at 1:10am
It is repeating again.  I rented an Opel Insignia here.  The new Buick is the same vehicle.  May dad bought one and it's an Opel with a Buick grill.  Anyway they have a switch on the console for the electrically operated parking brake.  Took me a while to figure that one out.  I guess the new Vette has it too.  I thought I'd give it a try as an emergency brake too so I flipped the switch driviing down the street with nobody around.  It's all or nothing!  I can't believe they are allowing this to be implemented. 

Title: Re: Does anybody have a working parking brake? How?
Post by Knotacare on Apr 17th, 2013 at 4:43am
The electric setup I have in the 68 does hold going forward, but if you forget to release it one time the break cable will have to be adjusted.    So it must be a very fine line as to the adjustment of the breaks. That solenoid pulls the break cable much tighter than the hand break, plus the cable is not kissing the drive shaft any more.
Line lock would work also although I've never seen it on rear breaks...I don't know why it wouldn't work. I wouldn't leave it on except to get through inspection
Alan [smiley=beer.gif]

Title: Re: Does anybody have a working parking brake? How?
Post by TX 73 stock on Apr 17th, 2013 at 7:34am
I'm just glad that Texas is flat. My e-brake is only tight enough so that the cable doesn't drag on the ground when I drive  :o :D :-?

Title: Re: Does anybody have a working parking brake? How?
Post by Knotacare on Oct 25th, 2013 at 2:54pm
I was talking to a guy yesterday that recent purchased 2 C-3 corvettes (1968 & 1975) that are in need of many repairs. Somehow the subject of parking breaks came up & he wants to look over my setup. He has over 50 motorcycles & has worked on parking break systems that are setup like our corvettes. He came up with a great fix that I think will work as long as you don't forget to release the break. On the parking break drum grind notches 1/16" to 1/8' about every 1" on the inside of the drum, these will allow the pads to grab much better. He swore it works & has been doing it for years.
Alan [smiley=beer.gif]

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