Working Man's Burbon

[HO455]

Dove into the brakes yesterday. The right front brake hose had a cut in the rubber sheathing and had been rubbing on the upper control arm and as I mentioned before the hard line was twisted and the fitting rounded. (Top photo) I'm surprised the WMB stopped as well as it did with the tube twisted and the rear wheel cylinder issue. (Whoops spoiler!) The fittings in the tee were frozen, as was the right side fitting to the hose. The fitting at the proportioning valve came loose so I cut the tubes at the tee and the right hose allowing me to put the tee in the vise and use a six point socket on the fittings and with some penetrating oil until they all came free with out damage. The tubing on the front brakes were two sizes. From the proportioning valve to the tee it was 1/4" tube and from the tee to the hoses it is 3/16". Pretty straightforward as I just matched the bends on the old tubing and flared the ends. Installed the new hoses in the tabs with the U clips and bolted the banjo fitting to the calipers making sure the hoses didn't touch anything throughout the suspension's range of motion I used Brakequip copper nickle tubing. It is easy to work with and if you want it can be polished to a great shine. It is standard equipment on Porsches and other high performance European cars. If you don't have a flaring kit or benders, I recommend Imperial tools, they work well, are reasonably priced, and I'm still able to get replacement parts for the set my dad bought in the early seventies. When we were half way through bleeding the front brakes I noticed that fluid was running out of the right rear brake drum. Tore it down and found the cylinder had a rusty spot that was allowing fluid past the seal cup. So two new wheel cylinders from NAPA. Which they had in stock, but it took two counter people and me 30 minutes to get the stupid computer to spit out the correct part numbers. I was sure glad I took my bad one with me. I got the right one installed, but ran out of time for the left side. I ordered up more tubing and will replace the rear tubing too. I'm not satisfied with how the lines on the rear axle are routed and how the flex hose is ty-rapped to the housing instead bolted down. This causes the tubing to flex every time the axle moves and to slowly work harden the tubing until it cracks. The brake adventure will be continued.

[LockDoc]

Originally Posted by HO455

Dove into the brakes yesterday. The right front brake hose had a cut in the rubber sheathing and had been rubbing on the upper control arm and as I mentioned before the hard line was twisted and the fitting rounded. (Top photo) I'm surprised the WMB stopped as well as it did with the tube twisted and the rear wheel cylinder issue. (Whoops spoiler!) The fittings in the tee were frozen, as was the right side fitting to the hose. The fitting at the proportioning valve came loose so I cut the tubes at the tee and the right hose allowing me to put the tee in the vise and use a six point socket on the fittings and with some penetrating oil until they all came free with out damage. The tubing on the front brakes were two sizes. From the proportioning valve to the tee it was 1/4" tube and from the tee to the hoses it is 3/16". Pretty straightforward as I just matched the bends on the old tubing and flared the ends. Installed the new hoses in the tabs with the U clips and bolted the banjo fitting to the calipers making sure the hoses didn't touch anything throughout the suspension's range of motion I used Brakequip copper nickle tubing. It is easy to work with and if you want it can be polished to a great shine. It is standard equipment on Porsches and other high performance European cars. If you don't have a flaring kit or benders, I recommend Imperial tools, they work well, are reasonably priced, and I'm still able to get replacement parts for the set my dad bought in the early seventies. When we were half way through bleeding the front brakes I noticed that fluid was running out of the right rear brake drum. Tore it down and found the cylinder had a rusty spot that was allowing fluid past the seal cup. So two new wheel cylinders from NAPA. Which they had in stock, but it took two counter people and me 30 minutes to get the stupid computer to spit out the correct part numbers. I was sure glad I took my bad one with me. I got the right one installed, but ran out of time for the left side. I ordered up more tubing and will replace the rear tubing too. I'm not satisfied with how the lines on the rear axle are routed and how the flex hose is ty-rapped to the housing instead bolted down. This causes the tubing to flex every time the axle moves and to slowly work harden the tubing until it cracks. The brake adventure will be continued.

Wow! That fitting looks pretty nasty. I really like the copper/nickel tubing, I have used it on my last three builds....

LockDoc

[HO455]

Today I removed the old rear brake lines. I found a smashed spot up where the front cross member and frame rail come together on the passenger side, the hard line above the pumpkin was rubbing the panhard bar,and the hose had several badly worn spots. (Photos 1&2) After some research I figured out why the rear hose is not correctly installed and just ty-rapped. When they swapped the six lugs out the PO took the brake lines and backing plates off of the 3:73 67 rear end and installed them on the 71-72 3:55 rear end. Which sounds great except for the mounting for the hose on the axle is completely different. The 67 Tee goes through a tab welded vertically to the upper rear part of the axle tube and is secured with a brake line clip. The 71-72 is secured by a 5/16" bolt through the Tee into a tab that is welded horizontally on the upper front of the housing. (Photo 3 which I stole from wpavlis here on the forum shows earlier 67 style. Photo 4 shows the 71-72 style on my axle along with a marvelous example of Ty-rapping and the hose that is ready to burst. The last photo shows the correct 71-72 hose). When I was trying to locate the correct 71-72 hose I learned that there are two versions for C10's one for leaf spring trucks that is 17" in overall length and one for coil spring trucks that is 20 1/4" overall length. Other differences are that on the early rear end the lines are 3/16" (7/16-24 flare nuts) from the Tee fitting to the wheel cylinders and the lines on the later one are 1/4" (3/8-24 flare nuts) from the Tee to the wheel cylinder. So to make my set up work I am running 3/16" tubing from the wheel cylinders to the Tee and then using 7/16-24 inverted flare nuts machined for 3/16" tubing. I had no problems getting the fittings local, but no one in town stocked the hose. Napa was the closest with a Friday noon delivery. The Napa part number I ordered is #36683 (Sure hope it's right). So when the hose arrives all that's left is to cut and flare the ends at the Tee. Blow the lines down and connect the new wheel cylinders and bleed. I didn't replace the lines from the master cylinder to the proportioning valve as the fittings going into the valve were frozen. I may try some soft heat on them to see if they will break free or I may just live with them for now. It just depends on how much I want another can of worms on my plate.
Oh and right off the get go I jack the WMB up and dive under it and one of the brand new KYB shocks is gushing oil out. Just %@*@#&$# wonderful! Only four miles on it.

[HO455]

The brakes got finished up today. The new hose for the rear fit like it should. The only issue came from the rear brake hard line. It has a coupler just under the passenger front floor board inside the frame. The headers are right there and it was very difficult to get the coupling tightened up. I didn't have room for two hands or the wrench and I needed to hold the coupling still and spin the flare nut to tighten. It took close to an hour to get both nuts tight in the coupling. After test a drive I am happy with the rear brake performance, but I think the fronts could be better. I will probably bleed them again in a hundred miles or so. On the test drive I noticed the drivers side door has a small gap at the top which whistles something terrible above 45 mph. I had time to quickly adjust the door but no time to test drive it and see if it was better. I also replaced the short piece of fuel hose that connects the front hard line to the rear hard line. It is inside the frame under the passenger seat. The PO said he had replaced it but it was starting to crack. I believe it is too close to the muffler. After I redo the exhaust and the mufflers are out of the way I plan on replacing the hose with a hard line.