1 00:00:09,375 --> 00:00:10,250 Good morning. 2 00:00:10,250 --> 00:00:13,208 This video, we're going to have a look at removing brake caliper 3 00:00:13,208 --> 00:00:16,291 and pads, measure and assess, and then refit. 4 00:00:17,125 --> 00:00:19,583 For the purposes of this demonstration, we're going to be using the rig. 5 00:00:19,583 --> 00:00:21,625 So that means we've got better visibility 6 00:00:21,625 --> 00:00:26,500 and we've got a brand new set of brakes, so we don't need to do the cleaning side of things. 7 00:00:26,833 --> 00:00:29,541 So if we remove the caliper first, so 8 00:00:29,541 --> 00:00:31,916 we're using 7mm Alan Key. 9 00:00:32,708 --> 00:00:36,666 Just be careful removing the caliper bolts that you keep them in the same order they come out as. 10 00:00:36,666 --> 00:00:39,375 Some vehicles do have them fitted and they're different lengths. 11 00:00:59,750 --> 00:01:01,041 Right, what we're looking for here 12 00:01:01,041 --> 00:01:05,500 as we remove them, we're checking to see the threads aren't damaged and everything is kind of moving smoothly. 13 00:01:06,666 --> 00:01:08,583 We can then take the bolts out. 14 00:01:12,750 --> 00:01:13,083 Right, 15 00:01:13,083 --> 00:01:17,166 and generally on an older vehicle, these will have corrosion and dirt on here. 16 00:01:17,375 --> 00:01:20,708 So you need to wire brush them just to clean them and then have really thin 17 00:01:20,708 --> 00:01:24,041 smear of grease for reassembly to save them from seizing later on. 18 00:01:24,458 --> 00:01:27,125 If they seize that results in 19 00:01:27,125 --> 00:01:31,041 uneven pad wear and failure of the components before their time. 20 00:01:36,041 --> 00:01:37,541 So as we can see with this one, 21 00:01:37,541 --> 00:01:42,000 they're both the same length, but always worth keeping them in order that they came off. 22 00:01:42,000 --> 00:01:45,416 So when we refit, the same component goes in the same slot. 23 00:01:46,125 --> 00:01:51,041 So to remove the brake calipers, we're going to need to compress the piston slightly inside, 24 00:01:51,375 --> 00:01:54,041 so especially on a car as well. 25 00:01:55,333 --> 00:01:57,583 If we remove the cap on the reservoir. 26 00:02:00,125 --> 00:02:03,708 Give it a wipe around on the top, we'll put that somewhere safe for refitting. 27 00:02:04,166 --> 00:02:07,250 And what we do is we put a small piece of rag in the top of that. 28 00:02:07,708 --> 00:02:10,208 What happens is when we compress the piston, 29 00:02:10,791 --> 00:02:13,208 the fluid level inside here will rise back up. 30 00:02:13,958 --> 00:02:16,041 If somebody's over filled it previously, 31 00:02:16,291 --> 00:02:19,708 that fluid will then spill over, run down the master cylinder 32 00:02:19,708 --> 00:02:22,541 and then the customer will think they've got a leak after you've done the job. 33 00:02:23,291 --> 00:02:26,583 And obviously, when we put it back together, we can clean the top of the reservoir 34 00:02:26,833 --> 00:02:29,791 and then put the cap back on and then we know the job's all square and done. 35 00:02:30,833 --> 00:02:34,291 OK. So to remove the caliper, we've got the slider bolts out 36 00:02:34,291 --> 00:02:37,958 so we can now need to take the clip off the side. 37 00:02:38,541 --> 00:02:41,083 OK, so I'll move around the other side with a screwdriver. 38 00:02:47,333 --> 00:02:50,083 What we can do now is we can remove the spring clip. 39 00:02:56,750 --> 00:02:58,791 OK, take care to kind of keep 40 00:02:58,791 --> 00:03:01,208 hold of it as it comes out because they are quite tight fit. 41 00:03:08,708 --> 00:03:10,541 But that clip is now free. 42 00:03:10,541 --> 00:03:12,625 So as you can see now, the caliper will move. 43 00:03:15,791 --> 00:03:18,541 So we give the caliper a slight twist to push the piston back in 44 00:03:18,541 --> 00:03:21,291 you can just see that fractional movement there that's all we need. 45 00:03:21,875 --> 00:03:24,916 And now we can remove the caliper itself. 46 00:03:25,125 --> 00:03:28,208 We've got the pads in situ and then we've got the brake disc. 47 00:03:28,625 --> 00:03:30,750 So what I'm going to do is I'm going to put the caliper 48 00:03:31,208 --> 00:03:33,291 on the frame for now just to keep it safe. 49 00:03:34,375 --> 00:03:36,375 And then I'm going to remove the brake disc 50 00:03:36,375 --> 00:03:39,458 because it is a new setup we can take it off quite easily. 51 00:03:39,458 --> 00:03:42,541 Sometimes you need a bit of a tap with a mallet just to remove it. 52 00:03:44,750 --> 00:03:47,416 OK, so this brake disc, vented disc. 53 00:03:47,708 --> 00:03:49,375 OK, so twin rotors. 54 00:03:49,916 --> 00:03:53,291 Measurement wise, we measure across there with a micrometer. 55 00:03:53,666 --> 00:03:56,125 We don't need to on this occasion because it's a new unit. 56 00:03:56,375 --> 00:03:58,791 But if you look on the side of there, 57 00:03:59,250 --> 00:04:03,541 we have actually got a thickness minimum limit of 20 mm. 58 00:04:04,000 --> 00:04:07,500 OK, if we measure this brake disc with the micrometer, and it's less than 20 millimeters 59 00:04:07,500 --> 00:04:11,166 or on 20, that's a recommendation for repair for the customer. 60 00:04:11,625 --> 00:04:13,958 OK, that's the minimum limit the manufacturer gives you. 61 00:04:14,500 --> 00:04:19,000 We're checking for cracks and uneven wear or any high spots where it's gone blue. 62 00:04:19,208 --> 00:04:22,083 So that discs OK as a unit so we can refit, 63 00:04:23,458 --> 00:04:25,375 OK, brake pads themselves, 64 00:04:26,333 --> 00:04:27,791 they are sided. 65 00:04:27,791 --> 00:04:29,875 So if we push this unit forward, 66 00:04:32,166 --> 00:04:34,291 there's a metal spring clip that holds it together 67 00:04:34,750 --> 00:04:37,416 can be a bit stubborn, so watch your fingers when it's coming out. 68 00:04:38,166 --> 00:04:39,875 So there's the outer pad, 69 00:04:40,500 --> 00:04:43,166 and then the inner pad will come out through the gap. 70 00:04:47,500 --> 00:04:48,708 OK, so the brake pads 71 00:04:48,708 --> 00:04:53,583 themselves, we're checking for integrity on the pads, we're checking for any cracks or wear. 72 00:04:53,916 --> 00:04:55,916 In there there's a slight chip on there. 73 00:04:55,916 --> 00:04:58,583 I wouldn't be overly concerned with that on a customer's vehicle. 74 00:04:59,083 --> 00:05:01,291 The friction material is bonded on. 75 00:05:01,291 --> 00:05:04,750 So if there's an issue with that becoming unstuck, that's dangerous to use. 76 00:05:05,041 --> 00:05:07,708 And then we ring the customer up and tell them to replace. 77 00:05:08,208 --> 00:05:13,541 Engineering practice, good practices to replace pads and discs as one unit because they wear together. 78 00:05:13,833 --> 00:05:18,916 If you put new pads on old desks, they'll wear out prematurely and an incorrect angle 79 00:05:18,916 --> 00:05:22,458 and then you'll be replacing the whole set sooner than you should have to anyway. 80 00:05:22,791 --> 00:05:25,750 So good engineering practice pads and discs on 81 00:05:25,750 --> 00:05:29,208 both sides to save uneven brake wear or poor performance. 82 00:05:30,208 --> 00:05:33,541 OK, so brake pads we can measure, you can use a steel rule. 83 00:05:33,541 --> 00:05:36,708 I quite like using a tread depth gauge because it makes life a lot easier. 84 00:05:36,916 --> 00:05:39,583 So we put the gauge on there, push through to measure. 85 00:05:40,208 --> 00:05:44,500 And if we have a look on there, we've got twelve millimeters of friction material left. 86 00:05:45,041 --> 00:05:48,583 OK, the MOT legal limit is 1.5 mm. 87 00:05:49,416 --> 00:05:50,833 Okay, but we have to measure it. 88 00:05:50,833 --> 00:05:55,541 We can't measure that on an MOT because we can't even take the wheels off, so we have to have a best guess. 89 00:05:56,625 --> 00:05:59,500 I would say if it's two millimeters, I'd recommend 90 00:05:59,500 --> 00:06:02,291 replacing them for the customer because it won't make the next service 91 00:06:03,375 --> 00:06:06,125 . OK, so we've checked the pads on both sides. 92 00:06:06,125 --> 00:06:07,125 We can measure this one. 93 00:06:09,625 --> 00:06:12,666 And yep, we're at twelve, which I'd expect because they're a new unit. 94 00:06:13,000 --> 00:06:15,416 if one pad is worn more than the other. 95 00:06:15,416 --> 00:06:18,916 There's either an issue with the slider pins themselves, it's stuck 96 00:06:18,916 --> 00:06:22,458 or we've got an issue with the brake caliper piston. 97 00:06:23,083 --> 00:06:25,375 OK, so while we've got the caliper off, 98 00:06:26,416 --> 00:06:28,541 we can check the piston condition. 99 00:06:29,625 --> 00:06:33,208 So we've got the slider sleeves there, we make sure they're free of dirt and debris. 100 00:06:33,500 --> 00:06:35,625 We've got a caliper seal. 101 00:06:35,625 --> 00:06:39,708 All that seal does is protect the piston surfaces from dirt ingress. 102 00:06:40,375 --> 00:06:45,791 OK, it's not the end of this caliper if that seal is split, as long as the components are corrosion free. 103 00:06:46,125 --> 00:06:48,250 We can advise it and then refit. 104 00:06:49,125 --> 00:06:50,625 Your piston itself. 105 00:06:50,625 --> 00:06:52,291 There's a little bit of corrosion on the inside. 106 00:06:52,291 --> 00:06:57,750 That's not a cause for concern, and we're just going to check it for free movement when we reassemble.