Author |
Message |
Rodney Peach
Experienced User Username: rodney
Post Number: 28 Registered: 12-2003
| Posted on Friday, 27 July, 2007 - 01:03: | |
Hi All, I have to change the rear brake discs on my car but there is a special tool for this I take it ? can anybody help me and show me what sort of tool it is ,and perhaps I can get one made up if it is not to complicated ,I would be very grateful for any details to this . Regards Rodney |
bob Unregistered guest Posted From: client-86-29-86-255.brig.adsl.tesco.net
| Posted on Friday, 27 July, 2007 - 03:04: | |
the tool is simple but because of the forces involved it is a hefty lump of steel which would cost a few bob to knock up. I would take the arms complete with hubs off the car and take them to an engineer who has a press which will make light work of the job. Do clean them before presenting to the engineer. I have seen hours spent trying to remove press fitted parts and lots of skinned knuckles and lots of lost finger nails and damaged parts when a few bob down the engineers sorts the problem out. While in there check the wheel bearings and change if required. Also check the metal brake lines that run down the trailing arms. This is a simple every day job PROVIDING the correct tools are used and not a collection of ever bigger hammers
(Message approved by david_gore) |
David Gore
Moderator Username: david_gore
Post Number: 737 Registered: 4-2003
| Posted on Friday, 27 July, 2007 - 14:14: | |
Hi Rodney, Further to Bob's advice, check what type of seals are fitted to the inboard [yoke] side of the hub. If they are the felt type, they can let water into the bearings over time especially in snow climates where snow build-up under the guard melts when the car is garaged, runs over the yoke and along the shaft into the bearing housing. Crewe Parts have a conversion kit to replace the felt seals with the far better, in my opinion, lip seals. When I replaced the rear bearings on drh14434, my 50 ton press would not move the yoke and I did what Bob suggests at a local engineering shop and their 100 ton press also failed to make an impression. A 200 ton press finally separated the yoke and driveshaft at 125 tons - the mating taper face between the yoke and driveshaft was heavily corroded from the above water penetration and the bearing housing was full of water [the car spent the first 10 years of its life in the North of England]. Another important piece of information, use a proper torque wrench when replacing the retaining nut [new of course - do not reuse the old one and hope you can create a new locking indentation elsewhere on the circumference] as the yoke can spin on the driveshaft if the torque is not spot-on. You might be advised to use an ordinary torque wrench with a multiplying adaptor however you are working at the limit of a typical 250ft-lb wrench to get the specified torque [450 to 525ft-lbs depending on chassis number] and I would not take this risk. Any 4WD vehicle repairer will have a proper 1000ft-lb torque wrench and should do the job at a reasonable price - just don't tell him what it is off!! |
Rodney Peach
Experienced User Username: rodney
Post Number: 29 Registered: 12-2003
| Posted on Friday, 27 July, 2007 - 15:24: | |
Hello Bob and David , Thanks for your advice ,See how we get on,I do have a few lorry garages not far away so perhaps that will be the best way. thanks alot Guys regards Rodney From Spain
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bob uk Unregistered guest Posted From: client-81-108-184-10.brig.adsl.tesco.net
| Posted on Monday, 30 July, 2007 - 02:51: | |
Also because the big nut in the middle has to be changed if it won't budge rather than strain yourself and bust tools cut the nut off. I find that if a flat is ground away until the the threads are NEARLY visible --- the steel goes blue due to heat and this outlines the thread--- and then the opposite side is ground away the nut will crack and drop off in 2 pieces sometimes assited with a blunt cold chisel and a 2 lb 'ammer. Blunt cold chisels are not actually blunt as such. They are rounded where the sharp edge is to a radius of say 1/8 inch and then polished a bit. The idea is that when the chisel is used it does not cut and puts a lot of shock/force into what ever is being worked. I can easily exceed 500 ft/lb of undoing torque ( or doing up when the correct spanner is not available but this is a bodge ). IF you have to do this support the part on something solid such as in this case an axle stand, if you try to shock a nut off by blunt chisel with out support the part will bounce around and not come apart.
(Message approved by david_gore) |
Paul Yorke
Frequent User Username: paul_yorke
Post Number: 58 Registered: 6-2006
| Posted on Tuesday, 31 July, 2007 - 02:12: | |
Here is the hub spliter we use. The central screw is a hydraulic ram / multiplier that are fairly common in puller kits. The plate bolts tightly to the yoke then just screw down the ram until it pops off. We used to have one with a 1 1/2" ram, but this one is much less work. Not had a problem getting a nut off with a 3/4" socket and bar + long tube. To hold the hub to undo the nut we let a ramp down onto a wheel and trap it there. We then put the hub studs into the wheel - You can then use the long bar easily. (Message edited by david_gore on 31 July 2007) |
Bill Coburn
Moderator Username: bill_coburn
Post Number: 913 Registered: 4-2003
| Posted on Tuesday, 31 July, 2007 - 12:01: | |
Hmmmm. I wonder whether anybody has bothered to look at my treatise on this procedure in Issue 63 of Tee One Topics? Perhaps its amateur status doesn't warrant a reference. Notwithstanding, I have since found that a 'professional' drops the swinging arm and gets somebody to stand on the brakes while he swings on the socket. This would almost have to be done on a hoist which I don't enjoy. Thankyou for the pic of the puller Paul it certainly is a monster and having bought a small hydraulic version many years ago for an arm and a leg I would be cautious about that outlay. My memories of the task locked onto the sheer problem of holding the assembly while the nut was undone and done up. Hence the massive plate a friend made up for me which may be seen om page 897. If that plate moved there would be measurable seismic activity! Using the Paul puller as per Factory instructions would work but for the sake of undoing half a dozen bolts you can get the whole lot out on the bench and really get at it. On the other hand noting the pressures I have experiences that were needed to separate the yoke from the drive shaft and those reported by David Gore I would wonder how many would have to resort to Bob's advice and cart the lot along to the local 4WD shop! The only problem I see with this is how to hold the assembly during pressing. The mounting stand I was lent did the job perfectly and most importantly safely! |
Paul Yorke
Frequent User Username: paul_yorke
Post Number: 59 Registered: 6-2006
| Posted on Tuesday, 31 July, 2007 - 18:11: | |
Bill, I'm not sure why people don't refer back to Tee One's . I suspect that it's either through forgetfulness or being unaware they are there. They are straight forward and more importantly - use equipment that can be made found 'locally' or 'home grown' Issue 63 - I had a quick look but couldn't find it! The puller looks massive but the ram is 4" and the four holes correspond with the yoke holes. The plate is certainly thick though. Although too expensive to buy a ram for home use, I would think that a local repair shop would have one. The plate is just 4 clear holes (to match the yoke ) and a threaded one for the ram. I would think that it would be cheap enough to have one made to suit the repair shop ram? You are right about using the brakes to stop rotation when undoing the nut. And yes you do need to jack the car up high or use a 4 poster ramp / pit. Undoing the left hand side is easier because you can stand on the tube. The right hand side involves "bench pressing" and is much more work. I ALWAYS take the whole assembly off the car as you suggest Bill. Holding the hub is the BIG problem. Trapping the wheel under a ramp to hold the hub is the secret there. ( I expect you could use wood and a car to pin it down at home. [If you are not lucky enough to have a spare one - Use old carpet to stop your tyre walls getting marked.] or pop around to the local garage with 4 poster ramps. ) With the wheel trapped the hub is held firmly and will be able to take many times more force than you can apply with no risk of falling or your vice / bench being overturned. "If that plate moved there would be measurable seismic activity!" Too right Bill! These hubs are heavy. It also means that you can use twice the length bar, with two people pulling it, sitting on the ramp using a 'boat rowing' movement. Hard to picture it? But it makes life so much easier, especially when it comes to tightening.
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Bill Coburn
Moderator Username: bill_coburn
Post Number: 914 Registered: 4-2003
| Posted on Wednesday, 01 August, 2007 - 00:53: | |
Well Paul thanks for the heads up on the Tee One's. I have actually given up putting them on the Federal Site because of this very difficulty. Last week I had 11 'complaints' that information known to have been in the library had disappeared. I am assured that with this strange WIKI system nothing is lost, it's just that it can't be found. Turns out that my correspondents who may be working on the engine of a Mark VI engine, find the relevant bits in the manuals, parts list and service bulletins, that Richard Treacy and I spent a large effort to scan and originally load. They then bookmark these spots for quick reference. Imagine their chargrin when up comes 'Page not available' or some such! But efforts are apparently being made to keep the library well stocked as even though I had not loaded Issue 64 to the Federal site, one has now appeared there. In that context be aware that Topics is available on the Victoria Branch web site and that of the Rolls-Royce and Bentley Enthusiasts' Web Site in the UK.
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Bill Coburn
Moderator Username: bill_coburn
Post Number: 915 Registered: 4-2003
| Posted on Wednesday, 01 August, 2007 - 08:37: | |
As an after thought I was chatting to an old friend who remembers the trauma we had with the first rear wheel bearing replacement. The most unusual approach he knew of was to chain the assembly to a tree which used to work until one day they pulled the tree out! I have also read recently a blog that feasts on work done on tractors and heavy earth moving equipment. Mind boggling Mr Holmes - mind boggling. The largest nuts I have ever seen secure the feet of the Sydney Harbour Bridge to the base of the pylons. I wonder whether they have kept the spanner in case they need a bit of a tighten and what what torque would they need - measured in ton/miles I expect! |
bob uk Unregistered guest Posted From: client-81-108-176-16.brig.adsl.tesco.net
| Posted on Wednesday, 01 August, 2007 - 07:34: | |
The tool in the pictures looks like it has a Churchill hydrualic bolt. This is certianly a heavy lump of metal not the sort of thing one knocks up in the shed with a pistol drill and hacksaw. I am fortuante because at work we have a 2 metre swing lathe which weighs-- must be 50 tons when we need to put serious torque into something we bolt it down to the very large cross slide which has tee slots and pull away because 50 tons is not going to move especially when it is bolted down into 1 metre of concrete. WE took a nut off a shaft using the chuck to grip it 1 inch square drive 10 foot lever and a block and tackle off a fork lift truck. The rear wheels on the truck came off the ground and the nut didn't move while we we discussing what to do next ( turn it off but nut costs £120 )When we heard a click and the truck slowly rested its wheels on the ground and then the nut came off by hand. So if there is access to a big lathe chuck it up and lock the gear box and try. The forum is very usefull the other day I was away from base trying to find a subsitute for an 1/8 whit open spanner not wishing to buy lots of spanners I needed to know which metric was closest --9mm A/F. Someone publish these on this site
(Message approved by david_gore) |