GLPoomobile 958 Posted October 12, 2008 When putting the caliper piston back in, I've put the seal in it's groove in the cylinder first, but do I put the dust seal into it's groove in the cylinder and slide the piston back in, and then jiggle the dust seal into place on the piston? Or do I slide the piston in first, and then fit the dust seal once it's in? Haynes says it's the latter, but I don't see how I'm going to get the back edge of the dust seal in to it's groove between the piston and cylinder. It seems too tight a fit! Share this post Link to post Share on other sites
Atari Boy 11 Posted October 12, 2008 Sorry, I don't know either, but looking forward to seeing the answer. I am rebuilding calipers too. Share this post Link to post Share on other sites
Redtop 14 2 Cars Posted October 12, 2008 (edited) 1st without seals in make sure your piston is clean and goes in and out of the caliper. Put the seal in place then smear some brake fluid round it. Then put your piston fully in and then put the dust seal on which can be a bit futery:). Make sure you groove is clean so that it can go into place or it will just come off. Edited October 12, 2008 by Redtop Share this post Link to post Share on other sites
GLPoomobile 958 Posted October 12, 2008 Well I no know that you can't fit the dust seal before the putting the piston in. I tried but the piston got stuck half way, and when I pumped it out again, the dust seal had split. So back to trying it as per haynes, but it's a fiddly f***ing thing to do. Share this post Link to post Share on other sites
GLPoomobile 958 Posted October 12, 2008 Somebody must know how to get this damn seal back on! Please help! I've tried working the lip back under with a small screwdriver. I'm about half way around, but I'm damaging the seal and I can't get to the bit at the back where it's blocked by the caliper body. Surely this shouldn't be so difficult! Share this post Link to post Share on other sites
de Noir 0 Posted October 13, 2008 (edited) When putting the caliper piston back in, I've put the seal in it's groove in the cylinder first, but do I put the dust seal into it's groove in the cylinder and slide the piston back in, and then jiggle the dust seal into place on the piston? Or do I slide the piston in first, and then fit the dust seal once it's in? Haynes says it's the latter, but I don't see how I'm going to get the back edge of the dust seal in to it's groove between the piston and cylinder. It seems too tight a fit! Haynes is wrong on this. It's impossible to put the dust seal in place once piston is in. I've rebuilt 306 Lucas front calipers, this is the way to go: Fit the cylinder/piston seal first. Lubricate with brake fluid or red grease first. (you should get it with piston repair kit). Then put dust seal into the groove, lubricate first too. Lubricate the piston with brake fluid / red grease. As you see, lubricating everywhere is essential here. As in some aspects of life. Slide piston back in through dust seal and cylinder/piston seal. It's tight fit, you have to keep piston level and press hard but gentle, spreading your force equally. Kind of iron fist in velvet glove if you know what I mean. Once piston in place, push it down the cylinder until you're able to fit other side of dust seal correctly. I used new dust seals, old ones may tear apart, true. Good luck. Edited October 13, 2008 by MH_ Share this post Link to post Share on other sites
GLPoomobile 958 Posted October 13, 2008 That is how I thought it should be done, but when I tried it, it was far too fiddly trying to keep the dust in place while stretching it over the piston to the piston in to the cylinder. In the end I've done as per haynes, and I've got it under the lip most of the way around, but can't fit the last 10 percent at the back where the caliper body blocks access. So I'm just going to have to trust it stays put. That's cost me 2 rebuild kits already, at a tenner each. I wish you could get the dust seal individually. Share this post Link to post Share on other sites
de Noir 0 Posted October 17, 2008 That is how I thought it should be done, but when I tried it, it was far too fiddly trying to keep the dust in place while stretching it over the piston to the piston in to the cylinder. That's strange, as far as I can remember, everything went smoothly. I suggest you try "our way" again, and keep everything well greased - there should be no problems. I wouldn't trust keeping it 90% fitted. Share this post Link to post Share on other sites
marksorrento205 80 Posted November 6, 2008 Haynes is wrong on this. It's impossible to put the dust seal in place once piston is in.I've rebuilt 306 Lucas front calipers, this is the way to go: Fit the cylinder/piston seal first. Lubricate with brake fluid or red grease first. (you should get it with piston repair kit). Then put dust seal into the groove, lubricate first too. Lubricate the piston with brake fluid / red grease. As you see, lubricating everywhere is essential here. As in some aspects of life. Slide piston back in through dust seal and cylinder/piston seal. It's tight fit, you have to keep piston level and press hard but gentle, spreading your force equally. Kind of iron fist in velvet glove if you know what I mean. Once piston in place, push it down the cylinder until you're able to fit other side of dust seal correctly. I used new dust seals, old ones may tear apart, true. Good luck. As above just done mine, loads of fresh brake fluid I found was the key. I found the grease a bit to sticky, and they flew in Share this post Link to post Share on other sites
hoody_g 4 Posted November 10, 2008 I placed all the seals first with plenty of grease and then slid the piston through the dust seal. It is very trick and time consuming. Once you get part of the piston base in then gently work the rest round and the piston should just slide into position. It should end up looking like this, HTH Share this post Link to post Share on other sites
