How to mod a late booster for MK1.

[karmen]

i used to repair Mercedes / ate boosters in the 80's
they can be opened up and altered other ways as u would know

[dub be good to me]

Hey all, I have a Cordoba Booster and MC, but the MC only has 2 outlets. Anyone know if I a 4 outlet Cordoba MC is a straight swap?
I.e, will it fit up to the brake booster, the bolt holes look to stay the same across most MCs but what abt the rod connection (booster > MC)?

Don't want to have to replace the booster as well if I can help it!

[gldgti]

Hey all, I have a Cordoba Booster and MC, but the MC only has 2 outlets. Anyone know if I a 4 outlet Cordoba MC is a straight swap?
I.e, will it fit up to the brake booster, the bolt holes look to stay the same across most MCs but what abt the rod connection (booster > MC)?

Don't want to have to replace the booster as well if I can help it!

yes, it should be. the 2 outlet one is for abs cars, hte 4 is for non abs. straight swap.

[dub be good to me]

Thanks for that, I've posted a 'Wanted to Buy'..

Was thinking of drilling and tapping my 2 outlet MC..
The casting is structured as if it was made for 4 outlets, but only 2 were drilled in the factory.

I figured I could remove the internals then drill and tap it to the required thread.

Does anyone have any experience with this? Kinda hesitant to mess with it if it is potentially dangerous..

[Jarred]

Hey Pete. I'm in the middle of doing this atm, any more info on how you wired up the switch/relay?

EDIT: some more info.

I've got the reed switch & 30A 4 pin relay.

The original setup has 3 wires:
-Red w.Black
-Blue & Brown
-Red w.Yellow
I've located all these going into the back of the fuse box.

With the relay I've got:
30 - 12Vdc
85 - Earth
86 - ?
87 - ?

with the switch:
Com - Earth
NC - ?

Pretty sure I have to connect the NC to 86, and 87 to the taillights. Or am I way off?

TIA!

[Peter Jones]

I forget exactly which wire it is, I'll have to crawl under the dash and have a look.

There's just one wire involved and all you need to do is earth it through your new pedal switch. From memory it was yellow.

Pete

[Jarred]

So it was just the wiring from the orig wiring straight to the reed switch? No 'need' for the relay then?

[Peter Jones]

Yeah, don't bother with the relay. Not enough current to bother.

Just work out which wires to bridge and run them to the switch.

Pete

[GRN_VAGN]

so you only need 1 wire from that group of 3 to actually trigger the brake lights?

If you could provide a little more info pete that would be tops.
I will be doing this swap in next week or so, Got the bigger drums, Cordoba Booster, and a Audi Master Cylinder (i think)

Cheers

[Peter Jones]

On your Mk1 There will be a small loom connecting the 2 switches to each other and a connector into the loom.

Remove that and throw it away. From the loom connectors take note of the colour of the two wires (There's only two on a MK1)

Find the other end of the wires under the dash, they'll be in the A plug in the back of the Fuse box. Cut 'em and attach your switch wiring there.

Unplug the A connector and use a multimeter to confirm you've got the right wires.

You could just replace your hydraulic switches too, they only last 30 years or so, a new mechanical one probably won't last as long.

Pete

[GRN_VAGN]

yeah, id rather the pedal switch, my lights tend to not work sometimes pretty unsafe.

Cheers for info mate.

[Peter Jones]

Bump. There seems to be a few people interested in this topic again.

[Shadow_Rusty]

Due to a really bad brake booster on my Mk1 Cabby, I've gotten my hands on a Mk3 brake booster and master cylinder for this mod...

Quick question though, as the Mk3 was 4 wheel disc, and the Mk1 is 2x disc and 2x drum, will I need a restrictor of some sort in the rear brake lines???

THanks guys...

Update:
Looks like I have another issue now...
The Mk3 I salvaged the parts from, only had 2 outlets on the master cylinder...

Now I need to chase up a couple of t-pieces...

[pepperwhite]

How to mod a late booster for MK1.

I found some on a w201 Mercedes at the wreckers.

Update:
Looks like I have another issue now...
The Mk3 I salvaged the parts from, only had 2 outlets on the master cylinder...

Now I need to chase up a couple of t-pieces...

[nickosy]

Does anyone know the part number or a link for the master cylinder as I've got a mk3 one with abs so it only has two ports instead of 4.