badgerspitfire Posted August 9, 2020 Report Share Posted August 9, 2020 I've recently done some work on the brakes. New rear drums and shoes first, and all was fine, the new LH caliper and hose, again everything worked fine, and this weekend (amongst other jobs on the car), new rotors and mintex pads, and a new RH caliper and flexi hose. The brakes work really well now, but the pedal travels a long long way before any braking starts (but when it does, the braking is better than ever). It is almost like nothing is happening apart from overcoming brake pedal spring pressure until a point when the brakes 'operate'. Interestingly, after I installed the new caliper the pedal was totally soft for several 'pumps' and I had to 'jab' at it to get it to start to build pressure. I've tried putting the handbrake on (to simulate adjusting back brakes) and it doesn't make any difference to the large 'dead zone' in the brake pedal travel. There are no fluid leaks. The system has been bled many times now too. Any advice appreciated. I'm nervous about driving it now in case the pedal just goes to the floor one day..... Link to comment Share on other sites More sharing options...
SpitFire6 Posted August 9, 2020 Report Share Posted August 9, 2020 I would adjust the rear brakes again first off. Forget the handbrake method. 2 Link to comment Share on other sites More sharing options...
Clive Posted August 9, 2020 Report Share Posted August 9, 2020 To eliminate the rear brakes, you could just adjust them (on the adjusters, handbrake disconnected) so they are locked, a pump of the footpedal should then take up teh slack at that end. If the problem persists, it is the fronts. If they are brand new calipers, I suspect they are the issue. Nick Jones has had issues with them on a car, down to poor design. Do a search, it is all on here somewhere.... (his solution was to rebuild some original calipers. It is not a seal problem, something to do with the groove where the seal fits I think) Link to comment Share on other sites More sharing options...
Colin Lindsay Posted August 9, 2020 Report Share Posted August 9, 2020 39 minutes ago, SpitFire6 said: I would adjust the rear brakes again first off. Forget the handbrake method. That really made a difference to my GT6 brakes; they were badly adjusted before, and took two pumps of the pedal to operate. Once I adjusted them properly they made a world of difference. Check the end of the brake pedal where it joins to the master cylinder under the rubber boot; the hole here wears oval and can sometimes need a surprisingly large movement of the pedal before operating the master cylinder. Link to comment Share on other sites More sharing options...
poppyman Posted August 9, 2020 Report Share Posted August 9, 2020 Clamp the hoses off and release one at a time until you find which corner is giving you the problem. Tony. Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 9, 2020 Report Share Posted August 9, 2020 excess hub end float will push the pads back , once you pump ,up a pedal and have got a pedal does it stay reasonable then disappear new pads also take a good bedding in before you firm up a pedal feel. what anti squeal shims are fitted metal or plastic ??? pete Link to comment Share on other sites More sharing options...
badgerspitfire Posted August 9, 2020 Author Report Share Posted August 9, 2020 The pedal travel is long even after pumping stationary, so the pedal feel stays the same and doesn't get better. The anti-squeal shims are metal. I've tried adjusting the back brakes again, it made a tiny bit of difference but still a very long pedal before the braking action starts (and it is good when it does, with the Mintex pads and new discs). They are new calipers so I'm thinking it might either be the new caliper problem that Clive mentioned, or could it possibly be the master cylinder? Link to comment Share on other sites More sharing options...
DerekS Posted August 9, 2020 Report Share Posted August 9, 2020 I had a problem with new calipers and was convinced I hadn't bled them properly. What was happening, when I took my foot off the brake pedal the pistons were going back into the calipers, "seal rollback" I think it's called, due to the seals and pistons being dry. I took the pads out one at a time and carefully pushed on the brake pedal to ease them out a smidgen, then pushed them back in. I did this 2 or 3 times on each piston and that cured the problem. Something to consider? Derek. Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 9, 2020 Report Share Posted August 9, 2020 it does sometimes happen that a Mcyl that works fine for normal but when given long strokes to bleed ends up with a underlying not overly obvious degrade gives up on bleeding just another idea for the pot Pete Link to comment Share on other sites More sharing options...
poppyman Posted August 9, 2020 Report Share Posted August 9, 2020 Clamping the flexy hoses will tell you whats wrong. Link to comment Share on other sites More sharing options...
Nick Jones Posted August 11, 2020 Report Share Posted August 11, 2020 On 09/08/2020 at 18:14, poppyman said: Clamping the flexy hoses will tell you whats wrong. This. My money is on seal roll-back on the RH caliper - as you seem to be saying everything was fine until you fitted that. If clamping the flexihose proves it is that corner then pop the pads out and carefully pump the pistons out a little. Then squeeze them back in until you can just barely get the pads and shims back in. Your pedal should now be up. If it is, the rollback theory is proven. With a bit of luck the problem won’t recur as the seals get the hang of their job, but if the pedal travel does increase over a few hundred miles, the seals are continuing to adjust to the wrong point. You can try repeating the above process and they may settle but definitely didn’t work for me. My problem was with repro type 16 calipers whereas Spitfire are type 14 and I’m not aware of problems with them..... 2 Link to comment Share on other sites More sharing options...
wimpus Posted August 12, 2020 Report Share Posted August 12, 2020 If its on a Spitfire.. are the rear brakes been build up right ? Seen a lot of spitfires with not much pedal pressure or deep padel travel with rear pads fitted wrong. Link to comment Share on other sites More sharing options...
NonMember Posted August 12, 2020 Report Share Posted August 12, 2020 6 minutes ago, wimpus said: Seen a lot of spitfires with not much pedal pressure or deep padel travel with rear pads fitted wrong. Oddly, the cars I've seen with the rear brakes built wrong - and it's 100% of the ones I've owned with the type in question - were the 2500S/Stag/TR7/Sprint type. The self-adjuster ratchets were mis-matched on all of them. However, I do know people fit the shoes backwards on the small cars, I just haven't had it inflicted on me. Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 12, 2020 Report Share Posted August 12, 2020 agree with wimpus rear shoe upside down is more common than it should be so always check that the rear (trailing shoe) must have the unused handbrake rectangular hole at the Bottom Pete Link to comment Share on other sites More sharing options...
badgerspitfire Posted August 12, 2020 Author Report Share Posted August 12, 2020 Rears checked ok. Correct orientation of pads (thanks to forum advice for that too). They are new calipers so will first try Pete Lewis' suggestion (and Nicks) above about 'lubricating' the calipers by getting the pistons to push in and out a bit. Will first try clamping the hoses off though to see if I can find which end is the problem. A job for early next week! Will report back. Link to comment Share on other sites More sharing options...
Gully Posted August 13, 2020 Report Share Posted August 13, 2020 On 11 August 2020 at 17:19, Nick Jones said: This. My money is on seal roll-back on the RH caliper - as you seem to be saying everything was fine until you fitted that. If clamping the flexihose proves it is that corner then pop the pads out and carefully pump the pistons out a little. Then squeeze them back in until you can just barely get the pads and shims back in. Your pedal should now be up. If it is, the rollback theory is proven. With a bit of luck the problem won’t recur as the seals get the hang of their job, but if the pedal travel does increase over a few hundred miles, the seals are continuing to adjust to the wrong point. You can try repeating the above process and they may settle but definitely didn’t work for me. My problem was with repro type 16 calipers whereas Spitfire are type 14 and I’m not aware of problems with them..... My original Type 16 calipers are now rebuilt and back on the car - and normal brake pedal travel has returned. The repro ones are now languishing in the shed, where they will stay! Expensive mistake... Gully Link to comment Share on other sites More sharing options...
Nick Jones Posted August 13, 2020 Report Share Posted August 13, 2020 Yep.... I have a pair of those door stops too. Nick Link to comment Share on other sites More sharing options...
Colin Lindsay Posted August 14, 2020 Report Share Posted August 14, 2020 10 hours ago, Gully said: My original Type 16 calipers are now rebuilt and back on the car - and normal brake pedal travel has returned. The repro ones are now languishing in the shed, where they will stay! Expensive mistake... Gully Who are these repro jobs coming from? We need to identify the supplier(s) and notify them of a bad batch. Am I correct in that someone stripped one down earlier to find the differences between the new ones and the originals? Link to comment Share on other sites More sharing options...
Clive Posted August 14, 2020 Report Share Posted August 14, 2020 1 minute ago, Colin Lindsay said: Who are these repro jobs coming from? We need to identify the supplier(s) and notify them of a bad batch. Am I correct in that someone stripped one down earlier to find the differences between the new ones and the originals? Yes, Nick did all that investigation and found the root cause. All the new ones likely from the same source, and will undoubtedly get the usual response of "first time we have heard that" or suchlike. Most people use their cars so infrequently they could take ages to discover the issue, then assume it is because the cars are old etc. Moral is, rebuild (or get rebuilt) the original calipers. 3 1 Link to comment Share on other sites More sharing options...
Colin Lindsay Posted August 14, 2020 Report Share Posted August 14, 2020 Thanks Clive. Nick / Badger: do they come in a box with any kind of brand name, or manufacturer's mark? Link to comment Share on other sites More sharing options...
Gully Posted August 14, 2020 Report Share Posted August 14, 2020 9 minutes ago, Colin Lindsay said: Thanks Clive. Nick / Badger: do they come in a box with any kind of brand name, or manufacturer's mark? Not that I can see. The images of them from all the main suppliers appear to be the same. I bought from ANG Classic Car Parts back in 2017 - they were posted out in a plain box. Gully Link to comment Share on other sites More sharing options...
badgerspitfire Posted August 14, 2020 Author Report Share Posted August 14, 2020 5 hours ago, Colin Lindsay said: Thanks Clive. Nick / Badger: do they come in a box with any kind of brand name, or manufacturer's mark? Nothing on the packaging. A plain brown box. My LH caliper was from Rimmers and the RH from another Triumph supplier whose name I've forgotten (the club had sold out). Both look identical and pedal travel increased on fitting the LH, and is now awful with both 'new' calipers fitted. Fortunately, I've kept the old calipers so I can get them rebuilt if all else fails.... Update: Just had time to clamp off the front hoses to isolate the front calipers, and the problem is definitely with the front calipers......... The one from Rimmers isn't too bad (but still gives a bit of an unwanted dead zone). The other 'new' caliper (from James Paddock Ltd) is awful. Link to comment Share on other sites More sharing options...
Nick Jones Posted August 14, 2020 Report Share Posted August 14, 2020 13 hours ago, Colin Lindsay said: Thanks Clive. Nick / Badger: do they come in a box with any kind of brand name, or manufacturer's mark? Mine came from ANG too though, I reckon the same ones are available through many sources. There are no makers marks that I can see. Probably should have moaned to them, but by the time we've fitted them and worked out they were well out of warranty. I did discuss them with Bigg Red when I rang to order the rebuild kits for the OE ones I sourced to replace them. Initially he seemed to be saying that they supplied calipers to various Triumph specialists - then he cottoned on that I was moaning about them so "they must be someone else's" I did offer to send them for examination but the reaction wasn't that enthusiastic and I didn't feel like paying the shipping! Mr Badger...... presumably yours are Type 14s as it's a Spitfire? First time I've heard of the problem with them (heard of lots of T16s!). Does the one from Paddocks look the same as the Rimmers one? Might be worth trying the re-seat trick as mentioned above but if the T16 experiences are any indicator rebuilding the originals might turn out to be a safer bet. Nick Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 15, 2020 Report Share Posted August 15, 2020 from past memory club uses brake engineering for supplies Pete Link to comment Share on other sites More sharing options...
Gully Posted August 15, 2020 Report Share Posted August 15, 2020 I used Brake Caliper Refurbs in Rochdale to rebuild my Type 16 P calipers, although I did supply the new seals and SS pistons I'd sourced from Rimmers when originally planning on doing the work myself. Brake Engineering had nothing compatible on their website when I searched it and didn't seem to deal direct with the public for refurbishment. Gully Link to comment Share on other sites More sharing options...
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