Front Disc Brake Conversion

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   Just tonight I replaced the front driver side drum brake with a front disc brake kit from American Parts Depot, and I had a few concerns. First of all, I can't imagine it would but does having the caliper at different spots change performance or fit or anything? I just put it where it was most comfortable with slack on the rubber line, around 10 o'clock. Second, I was confused at the fact that the caliper, and both brake pads are just held in place with no bolts or screws of any type, and it didn't seem right to me that the brake pads just fit in and stay there, I would think that you'd want your brake pads securely fastened somewhere, and it just didn't seem right to me. And lastly, I read on multiple forums and websites about people having to grind down their pads since their rotor would no longer spin, and my rotor won't spin, I can get it to move maybe and inch if I get some leverage, and I was wondering if there was an adjustment to make, if the piston was self adjusting, or if I need to grind down my pads. It's a very very tight fit in there, and I tried to get the piston down as far as I could. Any help would be great, as I am very new to disc brakes and have worked only on drum before.P.S. I also finished my rear brakes and due to some previous mods from previous owners I seem to have to use a very annoying combination of '73 Javelin parts, and '68 Roadrunner parts just to get everything to fit, and I was hoping someone could shed some light over using parts from different sets, since now the parts are split about half and half.

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CoffinMaster Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/02/2018 Location: Los Angeles Status: Offline Points: 100	Post Options Post Reply Quote CoffinMaster Report Post Thanks(0) Quote Reply Topic: Front Disc Brake Conversion Posted: Sep/30/2018 at 2:35am
	Just tonight I replaced the front driver side drum brake with a front disc brake kit from American Parts Depot, and I had a few concerns. First of all, I can't imagine it would but does having the caliper at different spots change performance or fit or anything? I just put it where it was most comfortable with slack on the rubber line, around 10 o'clock. Second, I was confused at the fact that the caliper, and both brake pads are just held in place with no bolts or screws of any type, and it didn't seem right to me that the brake pads just fit in and stay there, I would think that you'd want your brake pads securely fastened somewhere, and it just didn't seem right to me. And lastly, I read on multiple forums and websites about people having to grind down their pads since their rotor would no longer spin, and my rotor won't spin, I can get it to move maybe and inch if I get some leverage, and I was wondering if there was an adjustment to make, if the piston was self adjusting, or if I need to grind down my pads. It's a very very tight fit in there, and I tried to get the piston down as far as I could. Any help would be great, as I am very new to disc brakes and have worked only on drum before. P.S. I also finished my rear brakes and due to some previous mods from previous owners I seem to have to use a very annoying combination of '73 Javelin parts, and '68 Roadrunner parts just to get everything to fit, and I was hoping someone could shed some light over using parts from different sets, since now the parts are split about half and half.

farna Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19676	Post Options Post Reply Quote farna Report Post Thanks(0) Quote Reply Posted: Oct/04/2018 at 7:00am
	The pads are a loose fit on the calipers, nothing holding them in except the caliper body and rotor. Position of the caliper is dependent on the bracket -- the caliper only goes on one way. Doesn't matter if caliper is to front or rear of wheel, but the bleeder screw must be pointing up. You can change position from in front of wheel to behind (or vice-versa) by swapping the brackets and calipers from one side to the other. When first installing you have to make sure the caliper piston is all the way in the body. This is usually done with a big c-clamp, screw end inside the piston. Tighten all the way down. If the caliper won't slip over the rotor with the piston known to be fully retracted the pads may be a bit thick. Some replacement pads are made with the assumption that the rotors have been turned at least once and may be slightly too thick. I'd use a coarse sand paper (like 50 or 80 grit) on an electric sander to "grind" them down, and take a bit off each rather than all off one. If it is a really minute amount, then take it off the outside pad as the inside (against piston) generally wears a little more than the outside. What type of brakes do you have? What did they come off of? AMC used three different types of single piston brakes, Kelsey-Hayes (have screw in pin guides), Bendix (these slide on the caliper frame), and Delco (on screw-in pin guides sort of like the K-H).
	Frank Swygert

CoffinMaster Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/02/2018 Location: Los Angeles Status: Offline Points: 100	Post Options Post Reply Quote CoffinMaster Report Post Thanks(0) Quote Reply Posted: Oct/14/2018 at 8:44pm
	They're the Bendix ones from American Parts Depot. After a bit of fiddling I found out how it all went together and it's all good now. Turns out I forgot a washer between the rubber brake hose and the caliper and the threads going into the caliper went so far in that they would raise the piston and hold it in place. Once the washer was on it was all good. My bleeder screws are at the top of the caliper but they are facing forward, would that cause any problems? Right now my main problem is that I am getting a constant flow of brake fluid from all of the bleeder screws front and rear, but my brakes are practically nonexistent. Is there any chance there is a large bubble going back and forth when I bleed the different sides? And if so could I fix it just by only bleeding one corner for a long while?
	1973 AMC Javelin AMX, 360 727 1970 Mercury Cougar, 351C AOD

304-dude Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Sep/29/2008 Location: Central Illinoi Status: Offline Points: 9082	Post Options Post Reply Quote 304-dude Report Post Thanks(0) Quote Reply Posted: Oct/14/2018 at 8:57pm
	I assume you got a new master cylinder, for the disc setup. You probably did not fully bleed the master cylinder before bleeding the brake lines. If so, you need to bleed the master, and then re bleed the brakes.
	71 Javelin SST body 390 69 crank, 70 block & heads NASCAR SB2 rods & pistons 78 Jeep TH400 w/ 2.76 Low 50/50 Ford-AMC Suspension 79 F150 rear & 8.8 axles Ford Racing 3.25 gears & 9" /w Detroit locker

CoffinMaster Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jul/02/2018 Location: Los Angeles Status: Offline Points: 100	Post Options Post Reply Quote CoffinMaster Report Post Thanks(0) Quote Reply Posted: Oct/14/2018 at 9:04pm
	Yes I got a front disc rear drum master from rockauto thats supposed to be for javelins. I bled till there were no bubbles in the master, then bled till no bubbles from the bleeders, but I'll go through it again.
	1973 AMC Javelin AMX, 360 727 1970 Mercury Cougar, 351C AOD

farna Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19676	Post Options Post Reply Quote farna Report Post Thanks(0) Quote Reply Posted: Oct/15/2018 at 6:06am
	Probably still air in the lines. If all was new it can take a good bit of bleeding. As long as the bleeders are the highest point of the caliper (piston body) it doesn't matter if they are forward or rearward.
	Frank Swygert