colin weston Posted January 27, 2020 Share Posted January 27, 2020 Thanks Mike and Derek for your replies. I have had further clarification from Ate that they are exclusively aftermarket suppliers. In view of Nick Fisher's extensive experience I have ordered a set of Bosch shoes. The fundamental problem with the parking brake is that it is a poor design. I decided to do some calculations regarding the forces involved when operating the handbrake mechanism which I am, hopefully, attaching. Assuming a 40 lbf pull on the handbrake this exerts a tension in the primary cable of approx. 160 lbf using the approximate mechanical advantage of 4 (12in divided by 3in) giving a cable movement of 1.25in with 6 handbrake 'clicks'. Using the diagram of the lever I made an estimate of the rotation of the lever resulting from a 1.25in primary cable movement. This lever has a mechanical advantage of approximately 2 so the tension in the 'output rod is approximately 320 lbf. This tension is then distributed via a yoke to the two rear cables which must result in a tension in each rear cable of 160 lbf. I am not familiar with the mechanism at the brake drum which actually forces the shoes apart. Link to comment Share on other sites More sharing options...
mikefitz Posted January 27, 2020 Share Posted January 27, 2020 The actual mechanism that moves the shoes apart , (shoe actuator 77364022), has a kind of cam/lever action that makes it difficult to calculate any mechanical advantage. Its available if required for around £20. I have not found any significant wear in these. Tips for replacing the shoes. Its a bit of a fiddle but you don't have to remove the hubs. Note where all the springs are fitted before dismantling. Use an electrical cable tie to hold the shoe actuator in place as you assemble the shoes. Fitting the spring clip onto the hold down pins is not easy, I found compressing with a very small mole grip then fitting to the pin was the most successful method. When adjusting the shoes follow the Fiat instructions and back off 4 to 5 clicks. I suspect the shoe assembly needs some 'space' centre itself against the drum when activated. Mike Link to comment Share on other sites More sharing options...
Derek Uzzell Posted January 27, 2020 Share Posted January 27, 2020 Colin There’s a drawing here https://www.quora.com/How-does-handbrake-work-on-a-car-with-a-rear-brake-disc that shows a generic operating mechanism for a disc-with-drum operating arrangement. When remedial work has been carried out on a vehicle it's to be anticipated that, afterwards, certain things may not be better immediately. If worn-out dampers or damaged springs have been replaced a driver should notice an improvemen straightaway, but replacing the friction components of brakes (eg. replacing part-worn brake pads/shoes) when those components are still in good condition, may result in braking performance being worse than before until the replacement pads/shoes bed in. For handbrakes that operate the same pads/shoes as the main braking system, bedding in should be fairly quick, but when a Ducato X250’s handbrake is used only when the vehicle is stationary (as Fiat recommends) bedding-in can’t happen. GALFER products are made in Barcelona and, although Mikefitz has confirmed that the brake-shoe he examined carried a GALFER marking, there’s no guarantee that GALFER shoes were OEM for Ducato X250s in 2007 when yours was made. (Like Mike, I would have expected Fiat to have chosen a more common manufacturer like Brembo or ATE.) Realistically, given the quite small diameter of a Ducato’s rear brake drums and the weight of the vehicle, when a Ducato is moving retardation using the handbrake will never be great - the shoes and drum have too little contact area. Adjustment of the X250’s handbrake system was discussed in this 2011 thread https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/FIAT-X2-50-Handbrake-Adjustment/25588/ though AL-KO chassis Ducatos may differ in the arrangement that links the handbrake in the cab to the rear brakes. Link to comment Share on other sites More sharing options...
Hans Posted January 27, 2020 Share Posted January 27, 2020 The Alko chassis also uses a Bowden cable on the rear axle(s). And the wheels are fiat ducato etc. A critical point is the the T- piece which split the cable L/R. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted January 28, 2020 Share Posted January 28, 2020 The Nova Leisure website lists 17 different handbrake cables for AL-KO chassis https://www.novaleisure.com/towing-reversing/towing/al-ko-handbrake-cables The advert for each cable includes a reference number (eg. 1292940) and this can be used to obtain a price from the outdoorbits.com website that seems to be able to provide these cables. The quoted prices vary between £100 and £200 per cable (example here) https://www.outdoorbits.com/al-ko-handbrake-cable-1292940-p-7522.html As was advised earlier, there are UK firms that will manufacture ‘bespoke’ handbrake cables, but the cost would quite likely be no cheaper than buying the appropriate AL-KO cables. Link to comment Share on other sites More sharing options...
Hans Posted January 28, 2020 Share Posted January 28, 2020 Be Aware that AL-Ko has about 2000 chassis variants. The correct cable can only be defined by the chassis number. Or the green plate if still there by the ETi number. Fixed by one pop nail on the axle. I no longer drive that axle anymore. Just monique drives A t6 Vw. For hobby i do air suspension only. And that includes every single bolt that is in contact with the chassis rails. And my MGB And Jaguar E type in the shed. Citroen DS sold. Link to comment Share on other sites More sharing options...
colin weston Posted February 8, 2020 Share Posted February 8, 2020 Success at last! Supplied the Bosch shoes to the local garage for fitting and adjusting the handbrake. In their opinion the brake drums may not have had the preservative properly removed and this had affected the friction of the previous shoes. They thoroughly cleaned the drum before fitting the new shoes and on the brake test recorded an efficiency of 21%. It is interesting that the efficiencies of the front and rear service brakes were 30% and 23% respectively. These subsequently get added together to give a total service brake efficiency of 54%. Having driven home the short distance of some 1.5 miles without much braking I checked the temperature of the rear drums which were too hot to touch. In my opinion they shouldn't get very hot unless one is using the service brakes hard. I returned to the garage the next day and they rechecked the adjusters in the drums. Whether they were already backed off the recommended five clicks I don't know. Anyway, when I got home the drums were barely warm and the handbrake performance on a moderate hill was fine. Today I went out to find a steeper hill and the handbrake was fine both down-slope and up-slope with 5 clicks on the lever. Strangely, when I got home I checked the temperatures of the drums and found the nearside drum quite hot whilst the offside was just warm. At least I can now finally have confidence in the handbrake performance and maybe put this thread to bed! Link to comment Share on other sites More sharing options...
SilverLinings Posted July 29, 2020 Share Posted July 29, 2020 I’d like to add my findings on the problem of poor handbrake performance on the Fiat Ducato and its Peugeot and Citroen variants. We’ve owned three Motorhomes to date, all of them coachbuilts based on the Ducato, and never found the handbrake to be an issue. So when in October 2016 we decided to buy a panel van for conversion, we were pleased to find a smart 2014 Citroen MWB Relay in Appleby. On the test drive, I was surprised to find that the handbrake wasn’t very effective, so when we did the deal, we asked for this to be adjusted. On taking delivery, I checked that the handbrake was improved; and yes it was, but still not brilliant! After a month or so we SORNd it and started the conversion. Nearly 4 years later, it’s ready to be MOTd and put back on the road. I was concerned that this might be a problem at the MOT test. So I checked on all the forums. A lot of people have given a lot of advice on the issue, regarding careful adjustment of cables, shoes, trying softer friction compounds etc. What nobody seems to have picked up on is the handbrake lever itself, and in particular its mounting plate. I only stumbled across it by accident, when I decided to remove the lever for better access to the area behind the driver’s seat. The handbrake mounting plate just didn’t look right... My mounting plate looked bent; the upper and lower flanges were no longer parallel. The upper one provides a mount for the lever, and the lower one locates an end stop for the cable outer. This meant that the cable pull of the lever was no longer in line with the cable end stop. I presume that this had happened during the van’s 2 years and 150,000 miles of commercial use. When I re-mounted the lever, I carefully observed the two flanges when the handbrake is applied with some force. I was surprised to see that the upper and lower mountings were being squeezed together. Also because the top flange was distorted, the lever itself was a few degrees out of vertical. So ‘there’s your problem!’ Despite being made of 6mm steel plate, these mounts are not strong enough to withstand a really strong pull (perhaps of the kind needed when you’ve got a full load in the back of the van, AND the rest of the system is out of adjustment AND you’re on a steep hill). I’ve now re-squared up the upper and lower flanges, and welded a reinforcing bracket between them to stiffen up the whole assembly. I also adjusted all the linkages under the vehicle. The difference is noticeable. MOT is booked for next week. That’s one more thing off the worry list. Link to comment Share on other sites More sharing options...
colin weston Posted January 20, 2022 Share Posted January 20, 2022 I really thought all my handbrake problems were solved back in February 2020. Returning from a trip last year I noticed a rubbing sound from the rear at low speed which seemed to occur once per wheel revolution. I thought "Here we go again". As the handbrake had seemed to have lost some of its efficiency I decided to rob the bank and replace all the Al-Ko handbrake cables at almost £500. Unfortunately we are not well served with garages that will take heavy vehicles. I had the cables replaced last week prior to the MOT which then showed a handbrake efficiency of 21% which is about the maximum I believe can be achieved with this disc/drum set-up. Having taken the vehicle to a local hill for a test, upslope and downslope, the handbrake performed well at 6 clicks. However, the low speed rubbing noise was worse. I returned to the garage this morning and they said they had made an adjustment but on driving away the problem was just as bad and the handbrake needed 8 clicks to apply! I insisted that a mechanic came out with me to listen to the noise and I am booked in for a return visit next week to investigate further. The mechanic asked who fitted the new brake shoes and I told him they were fitted there 2 years ago. It is easy to assume that the rubbing is due to the brake shoes contacting the drum. Could it be a problem with the rear brake pads not clearing the disc properly? I know from experience with my previous cars that I have had problems with rear brakes due to lack of braking effort as I always anticipate as much as possible when driving to avoid unnecessary braking. Any thoughts would be appreciated. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted January 20, 2022 Share Posted January 20, 2022 As your Starburst is a 2007 model I assume its rear brakes are the ‘top hat’ type with the ‘foot braking' being via disk rotors and pads and the parking brake involving small-diameter central drums and brake shoes (example on this YouTube video). I would have thought it should be practicable to decide audilbly whether the noise is coming from the ‘handbrake' part of the rear brakes or from the ‘footbrake’ part by operating each separately while the motorhome is being driven. Basically, while the noise is happening, pull the handbrake on and see if the noise changes, and do the same thing with the footbrake. It might not be the friction materials making the noise: it could be something like debris that’s causing it, or part of the mechanism within the drum might be broken. Link to comment Share on other sites More sharing options...
Brian Kirby Posted January 20, 2022 Share Posted January 20, 2022 Just on this, I had a similar handbrake efficiency problem with a previous van which was remedied by removing the disc/drum and greasing the drum brake shoe actuation mechanism and shoe contact/pivot points. I was advised that it is a not uncommon problem with motorhomes, because they spend long periods standing compared to the commercial vehicles that are based upon. Basically there is a build of rust on the drum part of the top hat. To clear that it is a good idea to periodically apply the handbrake gently, at low speed, to knock off the dust. But above all I was warned specifically against applying handbrake at normal driving speed as the shoe arrangement in the drum makes it prone to grabbing and locking up if that is done. It is designed as a parking brake, and not as a service brake. So, car park or quiet road rather, than the middle of your local High Street! First gear, lift the lever slowly at little more than walking speed, maintain motion with the accelerator for a few yards, and don't let the handbrake ratchet engage by keeping the release button depressed throughout the manoeuvre. Applying the handbrake in this fashion worked without drama, and seemed to prevent the rust build-up that resulted in loss of efficiency when MoT time came around. Link to comment Share on other sites More sharing options...
747 Posted January 20, 2022 Share Posted January 20, 2022 A good tip for anyone with an AlKo braking system is to remove as much weight as possible from the rear of the van. If it has a rear garage, empty it. That way the rear wheels will 'lock' much easier on the brake efficiency test. A locked axle is a pass on the MOT, low efficiency is a fail. That's what happens with a brake design that was borrowed from a 4th Century Roman baggage cart. :D Link to comment Share on other sites More sharing options...
colin weston Posted January 22, 2022 Share Posted January 22, 2022 Hi Derek and other respondents, I went out in the van today with a riding mechanic, my neighbour, laying on the rear floor at and he confirmed that the noise is from the nearside brake assembly and the noise disappears when the handbrake is gently applied at low speed. Crawling under the van I confirmed that the forward brake cable, from handbrake lever to rear lever, is correctly adjusted as the rear lever leaves its stop just as the handbrake lever is applied. Trying to apply some grey matter to the problem the sound can only be produced by a brake shoe making contact with the drum. Why then does the noise disappear when the handbrake is lightly applied? Assuming the shoes and springs are assembled correctly and the adjuster has been backed off five clicks, the only other moving part is the shoe actuator. Maybe its not operating freely? I will keep you updated after I return from the garage next Tuesday. Link to comment Share on other sites More sharing options...
Tracker Posted January 22, 2022 Share Posted January 22, 2022 Some years ago we had similar issues with a 2004 Boxer. The MOT station wanted to charge a ludicrous price for new handbrake cable which they insisted was needed and assured me 'should' cure the prolems. Following advice on here from Nick Fisher, I removed the entire old handbrake cable, ensured all the years of muck, rust, solidified lubricants and corrosion were cleaned off, lubricated the pivot points and ensured all was running free and unimpeded and reassembled it all. Problem cured, MOT passsed, no more odd noises. As I recall, it was a mucky and time consuming job under the van - but I was younger and fitter then and it was a heck of a lot less costly than new cable!! Any decent mechanic familiar with how the system works should be able to do this easily as it is not technically demanding - maybe a commercial vehicle workshop rather than a car garage would do better? Link to comment Share on other sites More sharing options...
Tracker Posted January 22, 2022 Share Posted January 22, 2022 It was a long time ago now and my memory is not what it was, but I seem to recall there is a pivot lever just behind the gearbox, where the cable from the handbrake transfers leverage to the cable that serves the drums and it is prone to rain and road water and crud polluting and corroding it's action and if this is not cleaned and lubed any cable, new or old, will not work properly? Link to comment Share on other sites More sharing options...
Geeco Posted January 23, 2022 Share Posted January 23, 2022 When I served my apprenticeship as a motor mechanic in the mid sixties disc brakes were just new to the scene. Drum brakes were the "norm." Every time we riveted new brake linings onto the existing shoes or used bonded shoes they were placed on the brake shoe radial grinder to ensure the profile of the shoes when fitted to the vehicle were in sink with the drum Inside diameter. This action had two benefits; increased braking efficiency as a very high % of the shoe surface area was in contact with the drum and no high spots causing the kind of noise subject of this thread. Cheers, Link to comment Share on other sites More sharing options...
Derek Uzzell Posted January 23, 2022 Share Posted January 23, 2022 These YouTube videos relate to the type of rear brakes fitted to a Boxer/Ducato/Relay X250 vehicle The last video shows the handbrake mechanism in some detail and it looks like this 'floats' to allow the brake shoes to centre within the brake drum when the handbrake is applied. In Colin's case, having identified that the rubbing noise was coming from the nearside brake assembly, I'd have jacked up the vehicle on that side, removed the road-wheel and rotated the disk/drum assembly by hand to check at which point the noise occurred and see if there was anything visually obvious that might be causing it. I'd check for any play in the wheel bearing, as this could allow the backplate to touch the disk and I'd also check that the backplate itself wasn't damaged. It sounds like a brake shoe is still touching the inside of the brake drum when the handbrake is off and slackening off the adjuster should confirm whether this is happening. If that's the issue, when the disk/drum is removed 'highlight' markings on the brake shoes are likely to be apparent and such highlights could be removed by judicious use of a file. Back in the day, it was commonplace to take a file to replaced brake shoes of motorbikes to optimise braking performance. Link to comment Share on other sites More sharing options...
mikefitz Posted January 23, 2022 Share Posted January 23, 2022 The shoes are held against the backplate with springs. Its not uncommon for these not to be replaced or be fitted incorrectly on assembly. As suggested the shoe assemble 'floats' om the backplate, any weakness or incorrect fitting may allow the shoe to freely move and rub against the drum. A slight application will 'centre' the shoe and thus remove the rubbing noise. Its also possible a weak or incorrectly fitted spring could rub against the hub. The overheating reported is concerning as this points to incorrect assembly, poor adjustment, or sticking cables. This could damage the shoes or springs. Also the fitting of new cables, assuming these are the actuating cables that connect to the drums, require complete disassembly and reassembly of the drum and shoes. There can be issues with the rear calliper sliding pins sticking and thus giving unequal pad wear but this would not cause the symptoms reported. A new spring kit should always be used when the shoe assembly is replaced. Other causes could be distortion of the drum or or contamination of the surface caused by rust or transfer of brake lining material to the metal, this may need the disk/drum to be replaced. The hub bearings may be worn but this should be easy to determine. Mike Link to comment Share on other sites More sharing options...
colin weston Posted January 27, 2022 Share Posted January 27, 2022 Success at last! Didn't manage to clarify with the garage what the problem was as I seem to have become a little 'persona non grata' as they thought that I was questioning their competence. If they had driven the vehicle a short distance after fitting the new cables on the previous visit they would have realised that there was still a noise problem. Apparently they stripped everything down again and the outcome is that the noise has disappeared and the handbrake works fine on my test hill. Thanks to everyone for their advice. On to the next problem, I have found that part of my floor has succumbed to water ingress! It never ends does it? Link to comment Share on other sites More sharing options...
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