Palagius

Well-Known Member
hi,is it possible to put a complete,lock,stock and barrel dual system from a 3 on my '69 transitional (?) 2a 88,
this is due to needing,rather than wanting servo assist and the extra failsafe,
thanks in advance,
ryn
 
Yes, my 70 LWB has a S3 pedal box, servo and dual circuit. Cicuit is front / rear split and the S3 master cyl has the right displacements. Other than the piping the worst part is you have to cut the hole bigger for the S3 perdal box but its a faff rather than dificult.
 
You need to replace the 4 way union with a 3 way for the front circuit. The front circuit is the rear pipe on the S3 master cylinder - The line drops down to the chassis then splits to front OS and across behind the engine along the cross member to the NS front. The front master cyl line drops down and runs along the chassis top to the rear flexy then splits on the axle to OS and NS. I found it easier to put an in-line union behind the engine so I could make up the NS front line in two parts. Buy a decent "in-situ" brake flare tool and decide whether you are going all metric or all imperial. For a 69 I would go all imperial.
 
I have had 2 ex mil 109s and on both the port nearest the servo has gone to the rear port on the PDWA 4 way splitter and then to the rear. Is this wrong then?
 
I fitted a servo to my single line 10" brakes using the early 109 master cylinder.
 

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On page 70.00.00 sheet 2 of the series 3 manual it explains the master cylinder setup. On 88" it the front port and on 109" its the rear port that serves the back wheels.
Thats obviously with the appropriate master cylinder for the model, if you are putting a complete 109 system onto an 88 then I have no idea how that affects the brake balance....if at all.
 
Joe, that's really intersting, I've just looked that up, as you say its very clear, front to rear on SWB and front to front on LWB, but the Expedition Landrover site has the opposite:
109masterLines.jpg

This worries me, normally I would trust the LR manual but the Experdtion Landrover site gets the brake springs right where the LR picture is worng. Mine came connected like this picture and I repalced like for like so I'd like to get to the bottom of this.
 

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The ports on the master cylinder are (usually) different sizes. The rear port (nearest the servo) is 7/16 and the front one is 3/8. They have different colour plastic plugs to alert you to the difference (which you only notice when you have already stripped everything out and have not bought any 7/16 fittings :() On my 109 Ser3, the PDWA also has different size ports, with the 7/16 port going to the front brakes. So I assume the correct way is to pipe the front brakes to the rear port - that's how my 109 is set up. The 88 master cyl is the same with bigger rear port, but I'm not sure if the PDWA is different on the SWB?
I can't see why it would make a difference as the bore is the same for both ports of the m/c, but I guess they're different sizes for a reason!
There are two dual-circuit master cylinders for the SWB - one for 10" front brakes and one for the later 11" twin-cylinder brakes. If yours is a 2A I guess it has 10" front brakes.
 
bore is the same for both ports of the m/c, but I guess they're different sizes for a reason
Didn't make that very clear!:oops: What I mean is that the master cylinder bore is the same for both front and rear ports so the fluid pressure and displacement is going to be the same at both ports. Which makes me wonder why the ports are deliberately different sizes?
 
Well the fittings are different sizes like you say but the pipes the same diameter...... are we drifting into the territory of it doesn't matter?
 
Joe, that's really intersting, I've just looked that up, as you say its very clear, front to rear on SWB and front to front on LWB, but the Expedition Landrover site has the opposite:
109masterLines.jpg

This worries me, normally I would trust the LR manual but the Experdtion Landrover site gets the brake springs right where the LR picture is worng. Mine came connected like this picture and I repalced like for like so I'd like to get to the bottom of this.

Mines the opposite of that:confused:.
Everything seems to work as it should.
 
Yes I think theres a lesson to be learned here dunno what it is but its probably that theres a hundred different answers to any one question you can ask and a thousand opinions as to to validity of the answer to the aforesaid question.
The moral is get as much info as you can then make your own mind up.
 
update.my series 3 pedalbox with type 50 servo+master cylinder should be here tomorrow (touch wood),i was pleasantly surprised to discover wide 11 tls front brakes had been fitted in the past,which means i now have a spare set of shoes for the rear as i bought the whole kit,new pipes,unions,clips,3way junctions etc will be fitted,
bear with me but i now have 2 questions that might seem obvious to more learned owners,firstly,on my manifold i have the servo vacuum blanking plug,what is the correct name for the part to fit there for the servo pipe and where can it be obtained,secondly,should i go diagonally with the dual system or seperate front and back systems,i will not be carrying loads,
thanks,Ryn
 
Series pedal box and type 50 servo are incompatible. You also need to make sure you have a appropriate master cylinder for TLS brakes, its a larger bore than the master cylinder used for the SWB 10" setup.
 
Once you remove the plug, you'll need the adaptor 90513171 and the vacuum hose connector 569714. Both are available (e.g. Craddocks) but quite expensive for what they are. Someone may know what the thread is in the manifold, in which case you may find a simple hose tail adaptor that works. I had to drill and tap my manifold, so I just used a brass hose tail adaptor from a plumbing specialist.
The standard dual-circuit split is front/rear; I've not heard of anyone using a diagonal split, but someone might know better?
There's info about the type 50 servo on the expeditionlandrover.com website - I think you need the 90/110 brake pedal and possibly a cutout in the offside wing to fit it.
 

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