200 to 300 calliper conversion?

I have a 200Tdi with the 3 pipe brake callipers.
Just bought an axle off a 300 for the swivels, and it's got a tidy set of callipers on, but they're the single pipe type.
Can I fit them, and how?
Do I need to do the rear too?

Is this another one of those jobs no-one wants to touch? Dual line system may be designed to be more reliable, but with the condition of my parts I don't think I've got that advantage anyway, and the single line system seems simpler (less to go wrong) and easier to maintain.
I've been searching and found a couple of hints suggesting T junctions, but when I do the work I might as well replace my 20-some-year-old lines, so I'm hoping for a solution that involves as little bodging as possible.
As far as I can tell I determine primary and secondary lines at the cylinder, and run lines from these to front and back with the obvious splitters and flex,keeping lengths as close as possible to original.
I may have to hold on to the bits until I find a rear axle, and do front and back together. Brakes work just fine now that I've sorted my vacuum issue (parts look sad, but no effective leaks, discs are good), so no huge rush, but if the job is reasonably straightforward I'd like to do it while I've got the axle apart to swap the swivels.

Replace would be the best way, and bring the brakes up to the 300s spec. The 300 still has dual braking but instead of splitting the front calipers into two circuits there's now just the one.

So the front will now become the secondary circuit and the rear the primary circuit via the pressure reducing valve.
You can reuse your master cylinder the secondary side to the front and primary to the rear.

It's 18 years since looked a a 200 style master cylinder, my RR had the same thing, but if you have enough outlets from the secondary side you can install a separate pipe to each front calliper, if not then u will need a T piece.
Without looking at the manual the rear system remains the same.


Sent from my iPad Air on a train.

I've been wondering about this, partly to simplify & partly as 300 type / single feed callipers seem to be easier & cheaper to get hold of (also, heard you can use defender (single feed) & hi-cap callipers to get greater brake-force as they have longer pads
as to m/cylinders, easy one would be to use the 300 item??

I think??

Rich.

ps.
dont use 'tee' connectors unless absolutely necessary, can cause all kinds of hell with trapped air

Rich.

Much easer if u use the 300s pressure reducing valve (C) below with its direct single feed to each caliper, the rear remains similar with its T piece, also remember that the 200s pipe/fittings are imperial while IIRC, the 300s is metric so a bit of a pain if u try to mix and match.

Thanks Discool.
Totally with you on the T joints, Zed.

Here's what I've got :
two on master ns (right in pic) go across firewall to ns front wheel
os front of master goes to os front wheel
os back of master goes through front of slave (is that what that is?) to os front wheel and back of slave to rear wheels
(That amazing welding came with the used motor )

This all seems like a recipe for uneven pressure, and right now draining and bleeding is a matter of closely following along with the Haynes manual, which is OK, but i;d rather know what I'm doing.
I have four outs and four wheels, which seems like it could be nice and simple, but I'll bet it ain't.
Which side is primary?
A pressure reduction valve seems like a useful thing to have somewhere in this system. Is that the nut on the slave (is that what that is?)? And how would I get two rear brakes going through there?

discool said:

Much easer if u use the 300s pressure reducing valve (C) below with its direct single feed to each caliper, the rear remains similar with its T piece, also remember that the 200s pipe/fittings are imperial while IIRC, the 300s is metric so a bit of a pain if u try to mix and match.
View attachment 93791

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That means that ideally I'm looking at getting the rest of the 300 brake system, from the master cylinder all the way out, if that will fit my servo.

All I have off the 300 is the front callipers, but I'm on the lookout for a rear axle because my housing has some pretty bad rust, so I'll look for a complete one and then replace the whole brake system when I take the fuel tank out to do the floor.

"Which side is primary?" the two pipes on the left and right at the rear of the master are the primary circuit. If u remove the reservoir fill cap, inside u will see a vertical partition between the front and rear, as the primary has the larger volume of fluid the large area at the rear of the partition is the primary side.
At the front caliper the top piston is the primary circuit.

And I can't just plumb them one to each of the wheels? Wouldn't have any control over brake bias, but is that a huge problem?

Tell me more about hi cap brakes !

As for the pipes rather than mess about I got this kit

Look at this on eBay:

http://pages.ebay.com/link/?nav=item.view&alt=web&id=201275717065&globalID=EBAY-GB

Automec Copper Nickel Brake Pipe Line Kit Land Rover Defender 90 RHD

Vinlander said:

And I can't just plumb them one to each of the wheels? Wouldn't have any control over brake bias, but is that a huge problem?

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Just use the two secondary circuits to the front calipers, leaving two spare primary circuits blanked off one at the master cylinder and other where it leaves the pressure reducing valve.
Better still in fact is to install a new pipe work kit as shown above to match the 300 system and with a 300 pressure reducing valve, the only issue than is the pipe coupling to the rear calipers which will require an imperial to metric coupler which u will remove in the future if u decide to replace the rear calipers.

I think I have the flex on the 300 callipers, so I could get m/imp couplers on at that point and juggle the existing pipes around a bit. Then all I need is a couple of imp blanking plugs, and I can emulate the 300's brake system.
I understand that the primary system runs the rear because it has more fluid and has to run two sets of brakes, where the fronts have a line each. Is that right?
I'll most likely keep the bits and collect up the rest of the system and install it all at once, since I have more important gaping holes in my bodywork to prioritize, but really appreciate having a better understanding of my brakes. Also, chatting with my brother earlier today, I started thinking about putting my 200 gear into a defender, so I have to do some thinking.

Speaking of defenders, a bit of research tells me that 110 callipers should go straight on without modification, and that you need the dual line system to run vented discs, so mine might be worth something after all.

@discool, any reason why fronts go on the secondary circuit?
This has moved up now, so I need to know what I'm doing.

Vinlander said:

I think I have the flex on the 300 callipers, so I could get m/imp couplers on at that point and juggle the existing pipes around a bit. Then all I need is a couple of imp blanking plugs, and I can emulate the 300's brake system.
I understand that the primary system runs the rear because it has more fluid and has to run two sets of brakes, where the fronts have a line each. Is that right?
I'll most likely keep the bits and collect up the rest of the system and install it all at once, since I have more important gaping holes in my bodywork to prioritize, but really appreciate having a better understanding of my brakes. Also, chatting with my brother earlier today, I started thinking about putting my 200 gear into a defender, so I have to do some thinking.

Speaking of defenders, a bit of research tells me that 110 callipers should go straight on without modification, and that you need the dual line system to run vented discs, so mine might be worth something after all.

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you dont need dual line for vented discs,all defender calipers are single line vented or not

jamesmartin said:

you dont need dual line for vented discs,all defender calipers are single line vented or not

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Doesn't entirely make sense that you would.

Vinlander said:

@discool, any reason why fronts go on the secondary circuit?
This has moved up now, so I need to know what I'm doing.

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Don't know, a disc brake thing maybe, on the older braking systems when two pistons in each of the front calipers were being used as a secondary circuit, so then the remaining two pistons plus both the rear calipers were called the primary.
Should one of the circuits fail then even braking could still be achieved albeit somewhat reduced.
So different from the later 300 series and the ABS system different still.

discool said:

Don't know, a disc brake thing maybe, on the older braking systems when two pistons in each of the front calipers were being used as a secondary circuit, so then the remaining two pistons plus both the rear calipers were called the primary.
Should one of the circuits fail then even braking could still be achieved albeit somewhat reduced.
So different from the later 300 series and the ABS system different still.

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But when one of the lines went I had nothing, so the system just doesn't work?
Note not a fault with the master since the brakes locked up as expected with various combinations of old/new tires.