Master cylinder question

[shaun1.6ghia]

Hi guys, long time since I've been here. Looks like a lot has changed.

My problem is that I have a rear axle from a ford escort with 9inch drums.

Now putting new master cylinders in and trying to make sure they are correct as there are a choice of 2 different ones. The ones I have taken out don't have a slit in for the shoes and are around 14.5mm diameter piston.

Now the rs and ghia ones I have looked at are 17mm or 19mm.

Can anyone help explain what to buy?

[Vista]

You mean slave cylinders right?

 

This isn't a problem I've come across, anyone?

[shaun1.6ghia]

Rear brake cylinders. Sorry was tired beyond belief last night.

[shaun1.6ghia]

Checked the ones in my other escort and the diamiter is 12mm so different again lol

[Rally Pack 2000]

There were several 9in drum and cylinder combinations.

 

First type is the early Twincam/RS1600/Mk1 Mexico type that uses a single flat top piston cylinder with seperate adjuster that clips in the opposite end of the cylinder. Cylinder size 17.8mm

 

Second type sees the introduction of the dual cylinder with grooves at each end for shoe location. Using also a 17.8mm cylinder but being a duel piston cylinder the mounting and shoes are completely different to the first type.

 

Third type is the later found on the Metric Mk2 RS type which is the same basic layout of the second type but uses the 19.1mm Cylinders.

 

Now because the layouts of these is similar to their 8in countrparts you often find strange cylinders sizes thrown in there by all and sundry that make you scratch your head.

 

In Australia all Mk2s have 9in rear drums and they used the same 17.8mm Cylinders regardless of model including 2.0lt cars. I have found that with the extra weight bias at the front with the Pinto engined cars is that with the 17.8mm I find it too easy to get a rear drum lock up so I adopted the European RS spec 19.1mm and it has proven better. So my advice is firstly if its not required for an original Twincam/RS1600/Mk1 mexico then avoid the first Single piston type all together. You want one of the dual piston cylinder types. If you using a Kent engine then go for the 17.8mm Cylinders and if your using a Pinto then go for 19.1mm. Thats providing that you are using a standard RS bore size master cylinder arrangement.

[shaun1.6ghia]

Thank you rally pack 2000 that is the most helpful post I've see in a while. Yeah mine are twin and will be using the twin ones, the measurement seems to relate to the size of the master cylinder piston not the piston size on the brake cylinders as many different sellers putting different sizes on their products for the same cars.

Well instead of searching for what was in there I now realised that I have a Capri servo master cylinder with orange tags so going to match that.

My motor is real heavy as the axle is on a mk2 consul so will need the right brake cylinders.

After a quick search it seems it was from a 1.6-2.0l mk3 Capri with a 20.6mm piston.

So my two questions are;

1. What size brake cylinders do I need and is this correct as the stamp on the side of the casting sais girling74660294.4.Q312 and I believe the tags to be orange.

And 2. The capri's I have seen have the two further outlets plumbed to the front brakes and the single outlet closest to the servo to the rear. Now my mk2 escort has the closest split using t piece to the front brakes then the 2 furthest away, one goes to rear brakes and one has a bleed nipple. Which is recommended for a heavy car?

[Rally Pack 2000]

I must admit you lost me on that one. We only had Mk1 Capris here so Im unsure any spec regarding M2 and 3 Capris. I can only really give specs for whats standard on particular Escorts. If your mixing and match start with the 20.6mm ones since you already have them and see if it the drums are locking prematurely or not at all. And go up and down a size till you find the best combination.

[shaun1.6ghia]

Hi rally pack,

Do you have a picture of how your master cylinder is plumbed in?

 

The orange tags relate to a 2.8 master cylinder which is 20.6mm

[shaun1.6ghia]

P.s. There was no relation to mix-matching parts. I am trying to match brake cylinders to the master cylinder. As I was told at the local car part dealers that there was different sizes available for the same car.

I now have the correct part.

The other question was for info on why different master cylinders were plumbed up differently as they look the same.

Nobody replied with any info on their capris or escorts

[Rally Pack 2000]

Hi rally pack,

Do you have a picture of how your master cylinder is plumbed in?

 

The orange tags relate to a 2.8 master cylinder which is 20.6mm

 

Mine is completey standard with regards to booster and master cylinder. All our Mk2 Escorts regardless of Engine use the same RS/Mexico spec Master Cylinder. Front Disc/rear drum sizes. the only difference being the use of 17.8mm rear brake cylinders as opposed to  the Euro 19.1mm. So its all standard as pictured in any manual. If you want something of specific area I can try take a photo for you sure.