83 Trans Am Main Brake Line Replaced
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Joined: May 2003
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From: Central Ohio
83 Trans Am Main Brake Line Replaced
Well, it was a great day. I had just gone to the local indoor range to try out a new 9mm carbine and I was heading home while thinking, I need to check out that state park outdoor range south of Columbus OH. So I diverted from home and took I71 south. Traffic was fairly heavy but not too bad and I had no issues until I went to put on the brakes as I was exiting the freeway onto Stringtown Rd.
The brake pedal did a dive towards the floor. I was still able to stop but I definitely lost part of the braking system as well as noting the brake light came on.
I canceled my southward bound trip and limped home taking it easy and being very paranoid.
When I got home I noted the front section of the brake fluid reservoir was empty. Well, somewhere I had a leak in the back braking system. I filled the reservoir up and hit the brakes a few times. The puddle formed towards the middle of car, just driver side of center, right in front of the rear axel. It was the Main Brake Line right where it coupled into the rubber brake line.
Knowing that an 83 has lots of corrosion going for it I decided immediately to replace both the main line and the rubber line. I had replaced both back axle lines fairly recently so I thought those would be ok to not replace.
After cruising the 3rd Gen Brake board I had a pretty good idea that I need a 1/4 inch steel line to go from the Proportioning valve to the rubber hose. I Estimated it was 10 to 12 feet given the bends the line had to go through.
First things first. I needed to get a new rubber hose. I located one in Reynoldsburg Oh at the Autozone. I purchased the hose and noted it had standard threads for the common 3/16" line that is used to go to the rear wheel cylinders. BTW, this 83 trans am has rear drum brakes. If someone wonders how drums brakes differ from Disk brakes, wheel, disk calipers need to slide sideways so they have to have rubber hoses between the steel line and the caliper. Drum brake wheel cylinders don't move in relation to the axel so you can use steel line all the way from the rubber hose "TEE" end to the wheel cylinder.
Unfortionately the rubber hose had a pipe fitting on the main line end that autozone did not have an adapter for. I am guessing this hose is made to accommodate several different models and years. I needed a fitting that would take it from the pipe fitting on the hose to the 1/4" main line fitting. I figured NAPA was the way to go after confirming the larger Autozone did not have what I needed.
NAPA did not have one fitting but they did have two that got the job done. I also purchased 2 5' length lines and one 30" line figuring that should get me from the front to the back with some extra. I then went to harbor freight and purchased a line bender so I could make neat bends in the line where it snaked from the Proportioning Valve around the fender well and down under the front part of the car. I also got the couplers to join the 3 steel lines together. All in all it was 3 lines, 2 couplers, and two adapters. The price came to about $25.00. The price on the rubber hose from Autozone was about $17.00. The bender from Harbor Freight was about $7.00.
I was able to salvage the fitting from the front of the Proportioning valve that took the pipe fitting on the proportioning valve to a 1/4" steel line fitting. I noted that the brake line passed fairly close to the exhaust manifold so I tried to keep it as close to the fender well as possible.
I also noted that even with the car on ramps in the front and in the back I could not fit my pudgy belly completely under the car. I had to work from the sides and later from the back as there was more dzimmerm clearance from those angles. I am beginning to think I need to cut down on the carbs or get higher ramps.
The line was run, the rear axle lines unscrewed ok from the old rubber hose and I was able to get the old hose out of the fitting where it attaches to the car body. There was a large "U" clip that had to be removed. I used a vise grips on it and it came out pretty easy. As soon as I wiggled the rubber hose the main steel line broke completely in two about 1" from the rubber hose fitting which was heavily corroded. After removing the old hose and getting rid of the old steel line I put the new hose in place and snugged the axle lines into the "TEE" part of the rubber hose. I then attached the "TEE" end to the axle with the bolt that had held the old hose in place. It was a bit rusty but the threads were still in good shape. I ended up with about 20" too much brake line so I ended up make a loop right in front of the main line end of the rubber hose. I definitely did not want to try and cut the hose and re flair it. I used the line bender a few times to get the bends I needed without crimping or otherwise damaging the steel line.
Once it was all in place I tightened all the fittings and filled up the front reservoir. I ended up having to bleed the back brakes 2 times. I noticed that I seemed to have good pedal but when I started the engine up and the vacuum boost kicked in and the brake pedal got mushy. So after turning the car off I bleed again. I did get some more air out. I think the action of the vacuum boost kicking end helped drive air out of the Proportioning valve where I think it was hiding. The brake light went out after that operation also, telling me the proportioning valve center section had moved away from its warning area.
Things that could have been done better.
I could have gotten a fitted main line from http://www.finelinesinc.com/ . They did respond to my email and gave me a price of $60.00 for the 1/4" main line.
Being the cheap person I am I decided to go the way I did and also it saved me a few days and about 300 miles worth of traveling if I had driven to where finelineinc is located in Wadsworth Oh.
I did cheat in that I did not completely remove the old main brake line. I left it in place and tie wrapped the new line to it at 1 foot intervals. Everything was so rusted that I was afraid if I tried to dig the old line out I might cause a leak in the 3 fuel lines that are run along the same path as the brake line. If I wanted to do this right I could have run all new fuel lines while I was at it. They will probably need to be replaced eventually.
dzimmerm
The brake pedal did a dive towards the floor. I was still able to stop but I definitely lost part of the braking system as well as noting the brake light came on.
I canceled my southward bound trip and limped home taking it easy and being very paranoid.
When I got home I noted the front section of the brake fluid reservoir was empty. Well, somewhere I had a leak in the back braking system. I filled the reservoir up and hit the brakes a few times. The puddle formed towards the middle of car, just driver side of center, right in front of the rear axel. It was the Main Brake Line right where it coupled into the rubber brake line.
Knowing that an 83 has lots of corrosion going for it I decided immediately to replace both the main line and the rubber line. I had replaced both back axle lines fairly recently so I thought those would be ok to not replace.
After cruising the 3rd Gen Brake board I had a pretty good idea that I need a 1/4 inch steel line to go from the Proportioning valve to the rubber hose. I Estimated it was 10 to 12 feet given the bends the line had to go through.
First things first. I needed to get a new rubber hose. I located one in Reynoldsburg Oh at the Autozone. I purchased the hose and noted it had standard threads for the common 3/16" line that is used to go to the rear wheel cylinders. BTW, this 83 trans am has rear drum brakes. If someone wonders how drums brakes differ from Disk brakes, wheel, disk calipers need to slide sideways so they have to have rubber hoses between the steel line and the caliper. Drum brake wheel cylinders don't move in relation to the axel so you can use steel line all the way from the rubber hose "TEE" end to the wheel cylinder.
Unfortionately the rubber hose had a pipe fitting on the main line end that autozone did not have an adapter for. I am guessing this hose is made to accommodate several different models and years. I needed a fitting that would take it from the pipe fitting on the hose to the 1/4" main line fitting. I figured NAPA was the way to go after confirming the larger Autozone did not have what I needed.
NAPA did not have one fitting but they did have two that got the job done. I also purchased 2 5' length lines and one 30" line figuring that should get me from the front to the back with some extra. I then went to harbor freight and purchased a line bender so I could make neat bends in the line where it snaked from the Proportioning Valve around the fender well and down under the front part of the car. I also got the couplers to join the 3 steel lines together. All in all it was 3 lines, 2 couplers, and two adapters. The price came to about $25.00. The price on the rubber hose from Autozone was about $17.00. The bender from Harbor Freight was about $7.00.
I was able to salvage the fitting from the front of the Proportioning valve that took the pipe fitting on the proportioning valve to a 1/4" steel line fitting. I noted that the brake line passed fairly close to the exhaust manifold so I tried to keep it as close to the fender well as possible.
I also noted that even with the car on ramps in the front and in the back I could not fit my pudgy belly completely under the car. I had to work from the sides and later from the back as there was more dzimmerm clearance from those angles. I am beginning to think I need to cut down on the carbs or get higher ramps.
The line was run, the rear axle lines unscrewed ok from the old rubber hose and I was able to get the old hose out of the fitting where it attaches to the car body. There was a large "U" clip that had to be removed. I used a vise grips on it and it came out pretty easy. As soon as I wiggled the rubber hose the main steel line broke completely in two about 1" from the rubber hose fitting which was heavily corroded. After removing the old hose and getting rid of the old steel line I put the new hose in place and snugged the axle lines into the "TEE" part of the rubber hose. I then attached the "TEE" end to the axle with the bolt that had held the old hose in place. It was a bit rusty but the threads were still in good shape. I ended up with about 20" too much brake line so I ended up make a loop right in front of the main line end of the rubber hose. I definitely did not want to try and cut the hose and re flair it. I used the line bender a few times to get the bends I needed without crimping or otherwise damaging the steel line.
Once it was all in place I tightened all the fittings and filled up the front reservoir. I ended up having to bleed the back brakes 2 times. I noticed that I seemed to have good pedal but when I started the engine up and the vacuum boost kicked in and the brake pedal got mushy. So after turning the car off I bleed again. I did get some more air out. I think the action of the vacuum boost kicking end helped drive air out of the Proportioning valve where I think it was hiding. The brake light went out after that operation also, telling me the proportioning valve center section had moved away from its warning area.
Things that could have been done better.
I could have gotten a fitted main line from http://www.finelinesinc.com/ . They did respond to my email and gave me a price of $60.00 for the 1/4" main line.
Being the cheap person I am I decided to go the way I did and also it saved me a few days and about 300 miles worth of traveling if I had driven to where finelineinc is located in Wadsworth Oh.
I did cheat in that I did not completely remove the old main brake line. I left it in place and tie wrapped the new line to it at 1 foot intervals. Everything was so rusted that I was afraid if I tried to dig the old line out I might cause a leak in the 3 fuel lines that are run along the same path as the brake line. If I wanted to do this right I could have run all new fuel lines while I was at it. They will probably need to be replaced eventually.
dzimmerm
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