land_rover_one_ten Posted April 8, 2011 Share Posted April 8, 2011 Hi All I became the lucky owner of a 1988 110 CSW last year. So far I have only had to replace the gearbox, transfer box, radiator, rear shocks, brake master cylinder, front brake discs and pads, rear drum shoes and have the foot-well patched so I reckon I got a good one Anyway I have been trying to improve the brakes which were frankly terrifying to start with. It's a 1988 110 so has discs on the front and drums on the back. I have had new discs and pads on the front and new shoes on the back. The wheel bearings and drums have been adjusted. And today a new brake master cylinder was put in. Braking is much better but still not what I would call 'crisp'. There is still a lot of travel in the pedal before the brakes kick in. Anyway while looking at the brake pipes I noticed something which has me confused. On my 110 the way the pipes are arranged the front discs are on the primary circuit and the rear drums are on the secondary circuit. But looking on page 493 here it looks like the rear drums should be on the primary: http://www.retroanaconda.com/landrover/parts_books/110/6_vehicle_controls_brakes_fuel_air_p472-579.pdf Am I reading the diagram right? The garage is saying it is safer for front to be on primary but will swap it if I wish. What do people think? Is there a reason that Land Rover put the rear drums on the primary? Could this explain the travel in the pedal? Should I swap things around? Cheers! Quote Link to comment Share on other sites More sharing options...
western Posted April 8, 2011 Share Posted April 8, 2011 this page from workshop manual will explain better than I can, my 110 is a '89 vehicle & same brake system as yours & lower left diagram on attached page. Quote Link to comment Share on other sites More sharing options...
mmgemini Posted April 8, 2011 Share Posted April 8, 2011 Have you still got the Pressure differential valve in the circuit. I've not worked on that system but I've been informed that it can cause problems. Quote Link to comment Share on other sites More sharing options...
land_rover_one_ten Posted April 8, 2011 Author Share Posted April 8, 2011 Hi guys Many thanks for the info. I think we could be onto something here. Looking at the diagram in western's post my brake lines are definitely the wrong way around. They come out of the master cylinder ok but then go into a valve mounted on the body. When they come out of this valve they seem to be crossed over with the secondary line going to the rear. Looking at western's document - top right it looks like diagram B - so a PDWA valve. What should I do? get the lines coming out of the PDWA valve swapped so the primary line goes to the rear bakes? Can I get a replacement PDWA valve as the one on my 110 looks original and rather rusty! Do you think any of this could explain the rather poor braking? Quote Link to comment Share on other sites More sharing options...
western Posted April 8, 2011 Share Posted April 8, 2011 Set the pipes up as per the attached page, if the PDWA is working OK & not giving suprious brake failure warnings, leave it fitted, not sure how much new units are, but I would guess not a cheap item, mines original too & still serviceable. Quote Link to comment Share on other sites More sharing options...
Diff Posted April 8, 2011 Share Posted April 8, 2011 Hi All I became the lucky owner of a 1988 110 CSW last year. So far I have only had to replace the gearbox, transfer box, radiator, rear shocks, brake master cylinder, front brake discs and pads, rear drum shoes and have the foot-well patched so I reckon I got a good one Anyway I have been trying to improve the brakes which were frankly terrifying to start with. It's a 1988 110 so has discs on the front and drums on the back. I have had new discs and pads on the front and new shoes on the back. The wheel bearings and drums have been adjusted. And today a new brake master cylinder was put in. Braking is much better but still not what I would call 'crisp'. There is still a lot of travel in the pedal before the brakes kick in. Anyway while looking at the brake pipes I noticed something which has me confused. On my 110 the way the pipes are arranged the front discs are on the primary circuit and the rear drums are on the secondary circuit. But looking on page 493 here it looks like the rear drums should be on the primary: http://www.retroanaconda.com/landrover/parts_books/110/6_vehicle_controls_brakes_fuel_air_p472-579.pdf Am I reading the diagram right? The garage is saying it is safer for front to be on primary but will swap it if I wish. What do people think? Is there a reason that Land Rover put the rear drums on the primary? Could this explain the travel in the pedal? Should I swap things around? Cheers! Rear drum brakes should be piped to the rearmost (primary) port on the master cylinder as already noted. If you have too much travel after bleeding, then the rear shoe adjustment is nearly always the culprit. The rear shoes have to be adjusted until they are very close to the drums to get a good pedal with little travel. Cheap brake shoes (britpart) have caused me trouble in the past because they wouldn't adjust properly (starting to drag but still a long pedal). Using quality shoes solved the problem on that occasion. Hope this helps, Regards, Diff. Quote Link to comment Share on other sites More sharing options...
mmgemini Posted April 8, 2011 Share Posted April 8, 2011 Teke Ralphs advice. If it's working. Leave it alone. Me. I'd bin it but then I think you need it for MOT. Quote Link to comment Share on other sites More sharing options...
land_rover_one_ten Posted April 14, 2011 Author Share Posted April 14, 2011 Hi All Just a quick update - I got the pipes swapped over this morning so that the rear is now primary - front secondary. The difference is subtle but I reckon it has made things better. Braking feels smoother and stronger. I even managed to lock the wheels up for the first time! There is still a fair amount of travel in the pedal despite the drums being adjusted up. To recap - new pads and disc on the front and shoes on the back. New master cylinder. All adjusted up. Is there anything else I can try? I have not done the brake hoses, should I replace those next? What about the braided ones do they make a difference? Quote Link to comment Share on other sites More sharing options...
western Posted April 14, 2011 Share Posted April 14, 2011 braided 'goodridge' brakes hoses will help, your existing hoses if original items will be soft 7 might be balloning when the brake pressure is applied, new hoses braided or standard will prevent this 7 make the brake feel better. my '89 110 has goodridge hoses fitted, they were a good improvement over the old standard hoses. Quote Link to comment Share on other sites More sharing options...
land_rover_one_ten Posted April 14, 2011 Author Share Posted April 14, 2011 Ok - I reckon I will go with some braided hoses. Can someone confirm this is the one for my 1988 110: http://www.modworld.co.uk/land-rover-defender-110-metric-1983---1998-goodridge-braided-brake-hose-kit-2533-p.asp Seems like a good price. Quote Link to comment Share on other sites More sharing options...
western Posted April 14, 2011 Share Posted April 14, 2011 Ok - I reckon I will go with some braided hoses. Can someone confirm this is the one for my 1988 110: http://www.modworld.co.uk/land-rover-defender-110-metric-1983---1998-goodridge-braided-brake-hose-kit-2533-p.asp Seems like a good price. talk to Llama 4x4 before you buy any, David is a member on here. http://www.llama4x4.com/page7.htm Quote Link to comment Share on other sites More sharing options...
Matt Neale Posted April 14, 2011 Share Posted April 14, 2011 Set the rear brakes up properly and bleed them with the shoes fully adjusted "on" so as to ensure you expel all the air, then readjust so that they just clear the drum. If you still have too much travel at the pedal, you can adjust the preload on the master cylinder. If you separate the master cylinder from the servo, you will see a short gub screw and locknut on mounted inside the servo - lengthening this screw will increase the preload on the master cylinder itself (and obviously, shortening it reduces the preload). You won't need to detach the brake lines from the master cylinder to carry out this adjustment so you won't have any need to re-bleed the system. HTH, Matt Quote Link to comment Share on other sites More sharing options...
onanblues Posted April 1, 2022 Share Posted April 1, 2022 @land_rover_one_ten I am pleased I found your post. My 1983 110 CSW had got the same cross-over with the primary and secondary circuits When re-piping all my brake lines, I faithfully copied the original pipes leaving the master cylinder to the PDWA. Later I discovered it was actually wrong, by referring to the same source as you. I firmly believe my Land Rover left the factory with this incorrect configuration. Quote Link to comment Share on other sites More sharing options...
western Posted April 1, 2022 Share Posted April 1, 2022 Can't be wrong as the master cylinder ports are different sizes & have different size nuts & threads on them, so they will only fit in the correct ports. Quote Link to comment Share on other sites More sharing options...
onanblues Posted April 18, 2022 Share Posted April 18, 2022 (edited) @western True. The ports at the master cylinder are different thread sizes. But at the PDWA the unions are the same, which is where they were crossed. Edited April 18, 2022 by onanblues Quote Link to comment Share on other sites More sharing options...
western Posted April 18, 2022 Share Posted April 18, 2022 See the diagram I posted ages ago in a earlier reply. Quote Link to comment Share on other sites More sharing options...
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