Brake troubles

Maintenance advice to keep your Spider in shape.
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jimincalif
Posts: 410
Joined: Sun Jan 25, 2009 12:43 am
Your car is a: 1980 FI Spider
Location: Lake Forest, CA

Brake troubles

Post by jimincalif »

I had a strong pull to the left when braking. Right front caliper seals were leaking. I ordered rebuilt caliper for Autozone for both sides. Went to install them today.

Installed the passenger side first, everthing came apart and went back together fine. Fluid ran out of the hose while I moved it from the old to new caliper. I had filled the reservoir to the brim and then refilled it once I had the caliper back on, it was down maybe 1/3 to 1/2. Then I bled it. Took a lot of pumping and let it sit a couple times for a while but got it done to clear fluid, kept the reservoir filled during this.

Then went to do the driver side. Unfortunately the threads in the new caliper for the banjo bolt were no good, the bolt just spun when trying to tighten it. Returned it to Autozone and they are sending a new one. Put the old caliper back on, seals don't look great but it is not leaking. Bled it.

So now my brake pedal goes to the floor. I can get some pressure, when I do, I still have my strong pull to the left, plus just much less braking in the front. I checked and bled the passenger side again, did not get any bubbles. I can see the caliper clamping down when the pedal is pushed.

Do I need to do more bleeding? Or ??? I was careful to never let the reservoir get below about 1/2. Help!
1980 FI Spider
rlux4
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Posts: 4211
Joined: Thu Jan 10, 2008 8:32 pm
Your car is a: 1982 2000 Spider
Location: Granite Falls, Wa

Re: Brake troubles

Post by rlux4 »

Bummer Jim. Are you fairly sure you never got air in the master cylinder? It will need bleeding if any did. If the pedal is going to the floor, then yes, there's still air in the system. When you crack the bleeder valves are you getting a good flow from both sides? You'll need to get good pedal before you can find out if the pull is being caused by something else, like collapsed hose, or sticky slides.
Ron
Ron Luxmore
rlux2n2@gmail.com
'82 2000 Spider: after 26 years between Spiders.
jimincalif
Posts: 410
Joined: Sun Jan 25, 2009 12:43 am
Your car is a: 1980 FI Spider
Location: Lake Forest, CA

Re: Brake troubles

Post by jimincalif »

Thx Ron, I'm sure I didn't let the fluid get below 1/2 in the reservoir, I kept refilling it frequently. Would the MC such air at that level? If so from what I've read I think I'm SOL, bleeding the MC sounds like it is above my pay grade.

Mark replaced the hoses at each corner last year with the braided cover stuff, so I think I'm good there.
1980 FI Spider
narfire
Posts: 3959
Joined: Sat Dec 27, 2008 2:14 am
Your car is a: 1980 124 spider
Location: Naramata B.C.

Re: Brake troubles

Post by narfire »

Are any of the fittings wet/damp? check at calipers, compensator valve. I had an issue at the flexable hose to the splitter on the rear axle. Never got the brakes to feel right and checked there... damp.. changed and tighten and good to go.
Brakes have tested several here's patience..mine included. (check some of Katsi's old posts)
With an assistant check at the MC. have one pump the brakes and crack at the MC,juice comes out? don't let air back in though.Do make sure you have plenty of rags under there as the fluid is a great paint stripper.
If you have access to a "Motive" pressure bleeder, the job can go really well.
Good luck
80 FI spider
72 work in progress
2017 Golf R ( APR Stg. 1)
2018 F350 crew long box
jimincalif
Posts: 410
Joined: Sun Jan 25, 2009 12:43 am
Your car is a: 1980 FI Spider
Location: Lake Forest, CA

Re: Brake troubles

Post by jimincalif »

Thanks. No pressure bleeder available (unless anyone reading this in Orange County Ca has one and would like to volunteer (I'll supply all the installation fluid you can drink! :D )

Where would I crack open the MC to see if I get air or fluid?
1980 FI Spider
So Cal Mark

Re: Brake troubles

Post by So Cal Mark »

Jim, bleeding the MC is pretty easy really. Clamp the hose from the reservoir and remove the hard line from the mc. Release the clamp and watch for clear fluid from the mc. Clamp the hose and install the hard line. Then do the other side of the mc
brunorahl

Re: Brake troubles

Post by brunorahl »

Put "Jim Bob" in the car. Have him hold down the brake pedal. Then loosen a line nut on the master cylinder until it weeps fluid. Once the pedal goes to the floor, tighten the line nut again. Repeat a few times for each line nut. Since it's not a new master cylinder, that should be enough to have gotten any air out. Also, try tapping things with something like a 13mm combination wrench. The vibrations can help shake free any trapped air. It's odd, but it's worked for me in the past.

There is a chance, if your master cylinder is old, that you tore the internal seals. Brake fluid absorbs water and will cause a master cylinder to rust on the inside. This won't typically happen in areas where your master cylinder piston makes normal pressure, but where it doesn't. On a long stroke, like when bleeding the system, you'll hit the rust areas and cut the seal. Sometimes you'll still get a bit of pressure, but never a strong pedal feel.
jimincalif
Posts: 410
Joined: Sun Jan 25, 2009 12:43 am
Your car is a: 1980 FI Spider
Location: Lake Forest, CA

Re: Brake troubles

Post by jimincalif »

Thanks everyone, I took a break from it last night and this morning. Went out a couple of hours ago to check everything again, and first thing is the brake pedal is nice and firm - nice, but car problems rarely fix themselves.

Looked for leaks, saw some dampness on the right front caliper. Had my wife mash the pedal and I was getting a slight leak where the hose connects to the caliper. The bolt was already pretty tight, and I used the new washers that came with the caliper, but I pulled the retaining clip and got maybe another 1/16th of a turn, this seemed to stop the leak, dried everything off, mashed the pedal and no fluid. Just for yucks since I was there I bled it a bit more just to check, did not get any bubbles at all.

Checked the driver side for leaks, didn't find any even though this is just the old caliper reinstalled with the old washers. Bled this side again, got a lot of miniscule bubbles, bled til it was clear and closed it up. Pedal is still firm.

I haven't bled the MC yet, figure I might as well wait til I get the new left front caliper to install.

Re the uneven braking, I'm wondering if this now has something to do with the new and old calipers? Left side has old caliper, after releasing the brakes there is still quite a bit of drag on this side, where the new passenger side seems to release better and spin freely.

Mark - if I can get this good enough to drive, I'd like to get it up to you to check over and maybe renew the rear calipers as well? Based on the torn seals in both fronts and assuming they are all the same age, I would imagine its not too long before I have problems with them. I really don't want to drive around with doubts about the brakes. Also like to discuss having some other preventative maintenance done as well.

Jim
1980 FI Spider
So Cal Mark

Re: Brake troubles

Post by So Cal Mark »

if the pedal is firm, don't worry about bleeding the mc. I'd be happy to look the brakes over, just let me know
hdhracerx

Re: Brake troubles

Post by hdhracerx »

hi, thanks for the responses to this post - helping me to "fix" my brakes today so I can drive my "new" spider more safely. I'm planning to update both my soft lines and pads to ss and green or yellow EBCs. I have the lines already in a box, just waiting to pick up proper size flare nut wrenches tonight.

I reviewed my manual and attempted to bleed my front calipers. Driver's side - no air, no problem. Unfortunately, the pass side bleed screw is already stripped and the replacements are on b/o from IAP, so that will have to wait.

However, I can't find the REAR bleed screws at all. They are neither shown nor mentioned in my manual, so can anyone tell me where I might locate them?

Also, my pressure bleeder is leaking on one of the m/c reservoirs at about 7psi i think because the plastic top of the reservoir is old and fatiguing - the cap threads on fine, but once snug pops and loosens. Is there a good source for these?

Thanks for any guidance.
So Cal Mark

Re: Brake troubles

Post by So Cal Mark »

the rear bleed screws are located on the caliper right next to where the hose screws in
hdhracerx

Re: Brake troubles

Post by hdhracerx »

ok, thanks!

I'll look again in the a.m. - or perhaps later tonight.

Tried to bleed the master cylinder this eve, but the 10mm wrenches I bought today were too cheap and flexy to loosen the flare nuts. Don't want to strip them, so either have to hire someone to do it, or wait for better wrenches. Still, will try the rears tomorrow and see what I can get working.
pc124

Re: Brake troubles

Post by pc124 »

This thread is very helpful.

My brake bleed is going well with one exception.

The input on the master cylinder (from the reservior) closest to the firewall leaks badly using the Motive bleeder.

The mc is new (part of this upgrade) as are all flexible lines and calipers.

I have new hoses from the reservior to the mc. And new clamps too.

Leak seems to at rubber gasket between mc and nipple.

I have fluid flowing to all 4 corners, but 1/2 of the brake fluid seems to be landing on the floor.

I am only pressuring the Motive bleeder to 5 psi.

Ideas?

Please help.

Thanks to all who have helped me get this far.
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