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88GT Rear Brake Issue Two by Notorio
Started on: 06-25-2015 04:27 PM
Replies: 13 (229 views)
Last post by: Notorio on 07-05-2015 12:43 PM
Notorio
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Report this Post06-25-2015 04:27 PM Click Here to See the Profile for NotorioSend a Private Message to NotorioEdit/Delete MessageReply w/QuoteDirect Link to This Post
Here is the other issue: a PO may have changed the rear brake hoses. I am not sure these are the correct ones on there. On the passenger/rear side, where I started my brake job, I noticed the hose was not clamped down but held in place with a zip tie. The hose itself looked fine with no clearance issues. I just looked at the driver side and discovered a major clearance problem. Please look at the pictures below.

This shot shows the whole set up:



This shot shows the use of the zip tie (either a bracket is missing or the hose is too short to reach the mounting boss):



This shot shows an abraded part of the brake hose (I think this looks pretty close to failure):



My thought is that I need to order some proper 88GT hoses. Should I have other concerns?

John
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Report this Post06-25-2015 07:05 PM Click Here to See the Profile for RaydarClick Here to Email RaydarSend a Private Message to RaydarEdit/Delete MessageReply w/QuoteDirect Link to This Post
The driver's side hose is normally held away from all the moving parts by a metal hook. I didn't see that in any of the pics.
The abraded hose? I would replace it. The other one? I'm not so sure, but I don't have any zip ties holding my stock hoses.
I'm not sure what they've cobbled together. If it's not leaking, and not in danger of being damage, it's probably okay.
OTOH, I bought the Fiero Store braided hoses. They were such a PITA to position correctly on the front (and yeah... I may have used a zip tie or two - I really don't remember) that I left the stockers on the rear.

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olejoedad
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Report this Post06-25-2015 07:34 PM Click Here to See the Profile for olejoedadClick Here to Email olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
Stock 88 rear brake hose have a U-shaped metal tube coming off of the caliper bolt block.
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Notorio
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Report this Post06-25-2015 08:01 PM Click Here to See the Profile for NotorioSend a Private Message to NotorioEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks, I see that now. I'll order two pronto and do both together.
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Report this Post06-26-2015 12:38 AM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreEdit/Delete MessageReply w/QuoteDirect Link to This Post
Don't drive until you fix this. Is cutting into the hose braid and can fail w/o warning.

Wrong hose and couldn't use bolt at support bracket.
Raybestos left rear from RA: (88 rear doesn't use middle bracket.)


if possible, get new rubber uses SAE J1401 hose. Many "pro" grade hoses.
see http://www.fiero.nl/forum/Forum2/HTML/129208.html

RA has Raybestos PG Plus Professional Grade hoses.

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Notorio
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Report this Post06-26-2015 09:30 AM Click Here to See the Profile for NotorioSend a Private Message to NotorioEdit/Delete MessageReply w/QuoteDirect Link to This Post
OK, picking up the OEM style today. Tried a little humor with the wife last night ... showed her the picture of the abraded brake line and asked her if she had anything to do with it? I was the only one laughing ...
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Notorio
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Report this Post07-02-2015 05:37 PM Click Here to See the Profile for NotorioSend a Private Message to NotorioEdit/Delete MessageReply w/QuoteDirect Link to This Post
Fiero Store parts arrived ... now working on the Passenger Rear brake hose. This is just barely threaded onto the caliper because I don't want to stretch the hose any further. It looks quite short to me. Now I am wondering if when the PO rigged up the Wrong Hose if he also moved or reoriented the mounting plate. This new picture shows the Right Rear now ... does that mounting plate look OK? Should the hose really be so tight that it is nearly kinked? Can't be right ...


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Patrick
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Report this Post07-02-2015 05:46 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Notorio:

This new picture shows the Right Rear now ... does that mounting plate look OK? Should the hose really be so tight that it is nearly kinked? Can't be right ...


Here's a picture I had previously posted of an '88 parts car which probably shows enough to quell your fears. As far as I know, the brake lines and mounts were all factory. Keep in mind that when the car isn't jacked up off the ground, the brake hose won't be pulled down to such a degree.

[This message has been edited by Patrick (edited 07-02-2015).]

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olejoedad
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Report this Post07-02-2015 09:50 PM Click Here to See the Profile for olejoedadClick Here to Email olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
/\/\/\
What he said....
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Notorio
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Report this Post07-03-2015 12:13 PM Click Here to See the Profile for NotorioSend a Private Message to NotorioEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thank you for the reassurances. So this is cool, the mounting bracket has a shaped cut out that the hose must match so it slips into it (at which point you can then push in the spring clip on the other side.) The hose from the Right Rear box wouldn't fit into the cut out in any orientation so I tried the hose from the Left Rear box and poof! it slipped right in. I don't have the driver/left side apart yet but hopefully the 'wrong side' will fit there to. Apparently I switched the two hoses at some point .

OK, so now for the next problem. The copper gasket on the hose flange/caliper surface side of the hose connection is leaking ... drip, drip, drip coming out of the bottom of the connection as indicated with the Red Arrow. Before installing I noted that both gaskets and all sealing surfaces were clean and had no scratches or imperfections. I have now tightened the bolt up to 80 ft-lbs and the drip is almost stopped. Does anyone know the torque specs? I'm getting nervous to tighten it further. In the many brake jobs I've done I have never had to tighten a copper gasket this tight, or so I seem to remember. If I don't go tighter, my next step would be to use the two new gaskets from the other box and try again.



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Patrick
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Report this Post07-03-2015 12:56 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Notorio:

I have now tightened the bolt up to 80 ft-lbs and the drip is almost stopped.


80 ft-lbs? That sounds like an awful lot to me.

I'd take that fitting apart and check to see if something is prohibiting it from seating correctly... and also make sure the bolt isn't simply bottoming out. You may need to be using an extra copper washer.
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Notorio
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Report this Post07-03-2015 02:14 PM Click Here to See the Profile for NotorioSend a Private Message to NotorioEdit/Delete MessageReply w/QuoteDirect Link to This Post
Patrick, you called it! This picture shows the old seal (from the old hose) on the Left and the new seal (from the new hose that leaks) on the Right. Clearly, there is something preventing 100% contact of the surfaces --- there are no furrows in the seal from the hose flange towards the bottom (no, I don't know what orientation the seal was on before removal ).

Looking at the threaded portion of the caliper hole where this bolt goes, it is 1/2 inch deep. If you stick a probe down to the piston skirt that is at 5/8 inch deep. If you thread the bolt in it only goes 1/4 inch deep and then stops!! The bolt threads look absolutely perfect so I guess this means that the thread in the caliper must have picked up something.

Groan ... if I have the right tap and I clean up those threads I will have to take the caliper completely apart again to clean out whatever the tap loosens up. Ughg.

Light going on ... perhaps I will try the idea of putting an extra gasket on there ...


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Report this Post07-03-2015 03:16 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post

You're experiencing a common problem. Read this thread HERE.

And read the following. Marvin has expressed this very well (as usual).

 
quote
Originally posted by Marvin McInnis:

Yes, copper crush washers can be reused, but they must be annealed first. New copper crush washers should already be in the annealed condition, so you normally should be able to use them right out of the box. (Copper will slowly age-harden at room temperature, though. Those copper crush washers you bought 10 years ago, even though "new," may need to be annealed before use.) When you install them the crushing process work-hardens the copper, so they become much less flexible and may not seal if you try to reuse them "as is." Heating the copper washers to annealing temperature (~1100 degrees F ... a simple propane torch will do) and cooling them back to room temperature will restore their ductility and allow them to be reused once or twice.

Soft aluminum crush washers work-harden when used, too, but they can't reliably be annealed using simple workshop tools and techniques. Just throw them away and buy new ones. I assume that the use of aluminum crush washers is becoming more common due to the increasing price of copper.

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Report this Post07-05-2015 12:43 PM Click Here to See the Profile for NotorioSend a Private Message to NotorioEdit/Delete MessageReply w/QuoteDirect Link to This Post
I finished the job up yesterday and discovered a few things:

1-the PO had switched the rear brackets when he did the rig with the universal brake hoses. When I was working on the Right rear/passenger side I didn't notice the little 'L' engraved on that hose bracket. When I switched to the Left/driver side the 'R' was very clear to see ... this is why the hose seemed too tight and stretched. With the brackets on the proper sides the hoses mounted about one inch closer to the caliper.

2-four of five local parts shops didn't have any copper seals available. Autozone carried a ten pack ($5) with about three different sizes represented. I was able to reuse the seal in the picture above and remount the hose to the caliper using three seals on each, two on the caliper side and one on the bolt side. These I tightened modestly and no leaks. Success!

Thanks for all the suggestions and advice. Now with a test drive behind me I'll check for leaks after each drive for the next week or so. Everything looks OK so far. I still will need to rebuild the driver side rear caliper but that will be another day. I'll keep an eye on the passenger rear for any signs of sticking or excessive wear.

John
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