landkeeper Posted July 29, 2009 Share Posted July 29, 2009 lads a friend of mine is having trouble with the braking system in his hybrid , it's a designa coil sprung 88" with a v8 auto with a series t/b .it's fitted with what appear to be rangerover axles with dual circuit front calipers and single rears , it has a 109 master cylinder and a 109 servo , the brakes are awfull on it to say the least !!. there are no sticking cylinders , new brake pipes and clean fluid a complete and proper bleed has been done with no improvement . the front calipers were then changed for defender 90 ones and also the master cylinder was replaced with a defender 90 one this has left no improvement either all i can think of is that the 109 servo isn't up to the job it appears to be working properly. a defender or disco one is too big to fit without cutting some of the wing/bonnet not a step he wants to take ,my recollection of some of the very early 90/110s was that they had remote servo reservoirs and was wondering would this be an option . any thoughts ideas that might help ?? Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 29, 2009 Share Posted July 29, 2009 An early Defender servo & master cylinder should fit with very little work - needs a ~10mm thick adapter plate to the pedal box bolt pattern, and a very slight trim to the top of the wing but not bonnet. I'm running an early 110 setup on my 109 with discs all round and it stops perfectly. I'd go for a 90 master on an 88 as the balance should work out about right. Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted July 29, 2009 Share Posted July 29, 2009 The master cylinder is the problem - it is desgined to drive drums not not calipers. Calipers have a much smaller friction area and require a much greater force to operate. Swap for a master cylinder/entire servo unit from something like a 90. Quote Link to comment Share on other sites More sharing options...
landkeeper Posted July 29, 2009 Author Share Posted July 29, 2009 that was tried james as we too thought that was the problem ,but it made no difference Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted July 29, 2009 Share Posted July 29, 2009 Ah - Didn't read that bit! When you say you have poor performance is it a very hard pedal, or a very soggy one? Quote Link to comment Share on other sites More sharing options...
landkeeper Posted July 29, 2009 Author Share Posted July 29, 2009 i havn't driven it for a few weeks but when i did there certainly wasn't a nice feeling pedal it came to an abrupt hard part,felt to me like a vacum problem then , but it's been worked on since then but i'm told the pedal feels normal now the brakes just arn't doing their job as they should and the autobox makes it 'more interesting' to say the least Quote Link to comment Share on other sites More sharing options...
tuko Posted July 29, 2009 Share Posted July 29, 2009 My hybrid is basically the same vehicle and I have a 110 master cylinder/servo that works perfectly for me. Todd. Quote Link to comment Share on other sites More sharing options...
Phil Hancock Posted July 29, 2009 Share Posted July 29, 2009 Been there with a 109 on RRC axles. Std 109 master and servo pedal box was ok ish when empty but loaded, oh dear! The original master servo set up as fitted when the axles were fitted was a 109 non servo master/pedal with a Rover P6 remote servo and that was brill. The series servo is not big enough. Early 90 servo/master adapted to the series pedal should solve the issue of the pedal box fouling the bonnet. Quote Link to comment Share on other sites More sharing options...
landkeeper Posted July 29, 2009 Author Share Posted July 29, 2009 todd how did you fit in the 110 servo we measured up an early 90 one today and the inner wing and wing top and prehaps the bonnet as its a series 2 one will all have to be modified to fit the 90 servo/master cylinder the brakes are still terrible the front will lock up in reverse , but in forward motion they are awfull dangerous in fact and what ever we do we can't seem to get much braking on the rear . its now defender 90 calipers front and rear 109 servo and a 90 master cylinder neww pads all round and fresh fluid good pedal and the servo is working Quote Link to comment Share on other sites More sharing options...
tuko Posted July 29, 2009 Share Posted July 29, 2009 When I'm in front of my computer later this evening, I'll post a picture and answer your question. Todd. Quote Link to comment Share on other sites More sharing options...
landkeeper Posted July 29, 2009 Author Share Posted July 29, 2009 thanks Quote Link to comment Share on other sites More sharing options...
steve_d Posted July 29, 2009 Share Posted July 29, 2009 You say they have been bled but there is quite a special technique for bleeding the RRC twin system calipers and if it has the brake fail switch in the side of the master cylinder that must also be withdrawn. If you know all this then tell me where to go. Steve Quote Link to comment Share on other sites More sharing options...
landkeeper Posted July 29, 2009 Author Share Posted July 29, 2009 no steve i don't tell people where to go as a rule , however we have done away with the rrc stuff now and fitted 90 gear all in good working order and still sh!te brakes the next plan is to fit a defender servo and see what difference that makes, allthough i have doubts and am erring towards there being something else wrong ie lack of vacuum its a v8 car engine from an sd1 or such like Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 29, 2009 Share Posted July 29, 2009 Here's mine - Series pedal box, 110 servo & master, Series 3 wing & bonnet, the only trimming was a little bit on the wing which is covered by the bonnet. Wing trim: Adapter plate (since made thicker as it was binding slightly): Quote Link to comment Share on other sites More sharing options...
landkeeper Posted July 29, 2009 Author Share Posted July 29, 2009 thanks it's for this old lady, this was last october, on the irish version of the macmillan,when he realised his v8 was water shy , and then he blew the rear diff that little stream was rising by about an inch a minute by the time we got him out it was nearly up to the window Quote Link to comment Share on other sites More sharing options...
tuko Posted July 29, 2009 Share Posted July 29, 2009 Of course I can't find the picture that I want, so the one below will be the best till day light. My 110 servo & master are clearly marked as LHD but I can't see that making any real difference to what FF has in his 109. If anything it seems that I have done less trimming on my fender top than he did. In my hybrid I have 90 calipers on the front and presently drums on the rear. Braking is good as it is, but I have a RR axle on stands in the garage that is being rebuilt so that I can change over to 4 wheel discs in the near future. still sh!te brakes & lack of vacuum Those two comments got me wondering, how do the brakes feel with the motor off? Do you have a hard pedal or is it spongy here? When the brakes are bled, is it just fluid that comes out into the canister or is there air bubbles to? Todd. Quote Link to comment Share on other sites More sharing options...
landkeeper Posted July 30, 2009 Author Share Posted July 30, 2009 no the pedal feels 'hard' all the time ,but does depress slightly maybe an inch when the engine is started ,allthough the travel of the pedal is only about 3 inches until the 'hard' part is felt.if the car is on the lift when the pedal is pressed you can see all the flexible hoses stifening it's almost as if there is not enough fluid moving around to work the brakes properly . however if you crack a bleed nipple there is a full travel of the pedal, the109 servo is out now and will be replaced by the defender one in the morning and we'll see what happens then Quote Link to comment Share on other sites More sharing options...
tuko Posted July 30, 2009 Share Posted July 30, 2009 If the flexi hoses are flexing/bulging excessively then they are well past their due date and need changing. I had a similar problem with my clutch a few years ago. The flexi hose between the bulkhead and the back of the motor was bulging way too much and in turn not enough fluid pressure was getting to the clutch cylinder.........Just a thought that you may want to look at if the Defender servo doesn't help............but we know that it will. Todd. Quote Link to comment Share on other sites More sharing options...
tuko Posted July 30, 2009 Share Posted July 30, 2009 Here are the images of my Master cylinder/servo setup. There is more trimming on my fenders that I thought last night, sorry. Also it may appear that everything sits rather high, but there is no clearance issues with the bonnet. Todd. Quote Link to comment Share on other sites More sharing options...
landkeeper Posted July 30, 2009 Author Share Posted July 30, 2009 thanks lads i'll let you know later how it goes with the defender servo/masterclyinder setup Quote Link to comment Share on other sites More sharing options...
Daan Posted July 30, 2009 Share Posted July 30, 2009 I used a modern defender pedal setup, with the pedal, which normally is in a Z-shape straigthened out. This moved the whole assy to the right, while the pedal pad stayed in the same pos (its a LHD). Another problem you will find is brake balance: on a SWB you will need to change the brake bias. A 90 normally has a brake limiter valve in the rear brake line. I did not fit this, but fitted very early 110 Calipers, which have about 25% larger area. However, my car still failed the SVA test with this setup, as it was overbraked at the back. This was solved with an adjustable brake bias valve. Daan Quote Link to comment Share on other sites More sharing options...
ajh Posted July 31, 2009 Share Posted July 31, 2009 There is also always the hydroboost approach, doing that for my 110 with Vanco kit. Not cheap but should work better than just about anything else and no more vac pump needed. Quote Link to comment Share on other sites More sharing options...
landkeeper Posted August 3, 2009 Author Share Posted August 3, 2009 just an update on this for those who helped ,firstly thanks for all the pointers and ideas , it now has a complete system from a early disc braked 90 on it married to the series pedal box and is working fine .the only conclusion we have come to is is that the 109 servo just is not up to the job of the discs etc Quote Link to comment Share on other sites More sharing options...
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