1988 Rear brake issues (Page 1/1)
ChuckR SEP 29, 07:49 PM
I keep coming back with more issues... Ok here is where I am now. When I bought my car a few months ago one of the obvious issues were the brakes were very soft. I have not driven the car much due to other issues needing to be tackled such as the suddenly breaking driver side deck lid hinge, a coil issue, several wiring issues including dying batteries from failing oil senders (Friday's request for help). Back story is this car sat for 9 years before I bought it. It did run and drive when I bought it as well.

I finally got to a point that I was ready to tackle the brake issue. I spent the majority of yesterday inspecting brakes and lines. I found no leaks. The pads are all good, they slide properly, nothing obvious wrong. I do notice that the original rear brake line is gone and a not very professionally ran new line has been installed. All of the hoses look new, the MC looks new, pads look like barely worn.

I proceed to use a air powered brake bleeder to pull all of the old fluid through the lines and get the air out. I do 3 corners (1 bleeder broke on right front another issue to tackle once i figure out this conundrum.) I check the brakes and they are still incredibly soft. on the jack stands I put the car in gear and hit the brakes to see how much stopping power I have in the rear. Pedal to the floor it stops idle in gear. let off even a little and it starts turning.

I decide maybe the harbor freight pneumatic bleeder may not be working correctly so I do a gravity bleed. Now I have bled through a complete quart of fluid. I am still getting air out of the lines. So I am thinking there has to be somewhere that there is a leak, I again go through all of the connections and follow all of the lines to inspect for a leak, I find no leaks damp spots etc. Where can all of this air be coming from? I am at a loss. is it possible that it is taking this much since that line had been completely changed and I should just keep bleeding? I read up and found some mention of failed cylinder seals on the calipers could be the cause. I hope not since replacement rear calipers for an 88 isn't exactly cheap or easy to find. In fact the only place I have seen rear calipers for an 88 is the Fiero Store at 125 a piece. A family member said to check the carpet in the car to see if there is weeping from the MC in the car. I have the car at my mothers in her garage so I dont have access to it to check that tonight, I am looking for directions to look once I get there tomorrow.

Also as a side thought I know that I can mount front calipers to the rear for the 88. Other than losing the parking brake is there anything else to worry about like throwing off brake bias? Car is an auto and there are no state inspections here. so other than not having an E-brake this could be a more cost effective repair than 250 for calipers. Also could always later install a hydro e-brake not that I plan to drift in the car though.

Another thought even though it is not cost effective just something I saw. has anyone thought of adapting the Wilwood P-brake calipers for use in the Fiero?

Thanks,
Chuck

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"HICCUPP" 1988 2.8 GT Ocelot SS exhaust

olejoedad SEP 29, 07:58 PM
Front and rear 88 calipers have the same diameter pistons, so using front calipers on all four corners will not affect the bias.
Camel SEP 29, 09:39 PM
Since you said the MC looks "new" try bleeding it first then try working your way down the line. The rebuild kits for a rear caliper are less than 10 bucks on rock auto and VERY simple to do if you are mechanically inclined.
Neils88 SEP 29, 10:47 PM
Have you closely inspected the brake line flex hoses? When they start to break down they can become "stretchy", leaving you with a spongy feeling brake pedal.

If you or anyone else are looking for a full set of (front and rear, used) calipers for an 88, I have a set that I no longer need and would be happy to sell cheap. I also have a set of pads and drilled/ slotted rotors all with less than 200 miles on them. I'm not sure how much it would cost to ship them, though it could be a little pricey since I live in Canada (Ottawa). If anyone is interested, send me a PM.
ChuckR SEP 30, 09:08 AM

quote
Originally posted by Neils88:

Have you closely inspected the brake line flex hoses? When they start to break down they can become "stretchy", leaving you with a spongy feeling brake pedal.

If you or anyone else are looking for a full set of (front and rear, used) calipers for an 88, I have a set that I no longer need and would be happy to sell cheap. I also have a set of pads and drilled/ slotted rotors all with less than 200 miles on them. I'm not sure how much it would cost to ship them, though it could be a little pricey since I live in Canada (Ottawa). If anyone is interested, send me a PM.



I have thoroughly inspected all the hoses and lines. The rear hard lines are new, still have the UPC stickers on them, The main line running back is new, not ran in original factory location. All of the rubber lines have been replaced with new.

Thank you everyone else for the suggestions as well. Looks like I will try to continue bleeding, if I cant get it bled out i will try the rebuild kit for the rears, if that dont work Will try the MC in case it is bad, and if that dont work i will replace the rears with new front calipers. Knowing the bias will not be off by doing that helps. Also I will send a PM on the gently used though not sure if by the time shipping is paid it will be worth it. ;/
fieroguru SEP 30, 09:14 AM
Bleeding, parking brake adjustment at the rear calipers (rear pad gap to the rotor), and master are likely contributors.
theogre SEP 30, 10:14 AM
88 basically have same brake system as other Fiero w/ minor changes and same problems.
See my Cave, Brake Service and rest or section.

Can try jack the rear so MC is level to a bit nose down the try to bleed the system.

Manually adjust the rears is a band-aid at best and rebuilding rears is often same because of crap pistons. Fools say can rebuild pistons themselves only have a small % getting them to work for a time, often a Short time. Rear pistons that fail to self adjust or DIY trying to rebuild them can fail completely and drag the pads causing noise, wrap rotors to a wheel fire.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

ChuckR SEP 30, 07:04 PM
I have great pedal now. under extreme standing on the pedal it locked up. Brakes are much better than before. But wow are they not near as good as I am used to. Maybe I need to look at the vacuum and make sure I am getting as much booster as I am supposed to. I don't know since this is my first time driving the car with what maybe normal brakes. I know locking up is not good but I figured since this car does not have antilock brakes it would do so much easier than it does. I know the booster is working some as I can feel the difference when the car is started and not. What are you experiences with normal Fiero brakes?