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Looking to upgrade sierra master cylinder
flanders - 10/9/17 at 07:05 PM

Hi all. my M/C is leaking so its time to change it.

rather than just replace with another sierra one, ive seen some info regarding using a smaller bore cylinder which give better pedal feel. ive seen lots of different info on here using the search function, im looking for the 'simplest' to install

my current set up is (i think) a sierra m/c with 3 outlets, one to the rear and 2 for the front with M10x1 fittings.
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could anyone give me sources for a smaller bore cylinder?
will my existing push rod work with suggested cylinders?
can i reuse my reservoir?


thanks


jossey - 10/9/17 at 09:11 PM

Contact ap racing they helped me years ago With one


martinnitram - 10/9/17 at 10:42 PM

I'm on with exactly the same job, only on a striker.

so far ive found out the fiesta mk 1 has a 19.05 bore and is very close to the sierra one, the mounting stud holes are orientated differently, but not right for me as the outlet ports foul the steering column, the Nova mk 1 is fairly close but so far only found one with 20.something mm bore size, looking at a Mazda familia one at present, 19.05 mm bore and ports on the correct side for me, trouble is its only 2 port and ours are 3, one used for brake switch.
As for the push rod ill probably adapt mine as needed to suit, although the mazda one looks close on the pictures and the rebuild kit is available for a tenner on the bay.

What calipers are you using? ive got wilwood powerlite 4 pots and the sierra M/C feels to big even with these on.


flanders - 11/9/17 at 07:45 AM

Yeah ive seen people mention the fiesta MK1 MC, do you have the part number/link handy? am i right in thinking it has 4 ports so one needs blocking off?

ive seen old Fiat (124?) ones mentioned too

my set up is sierra rear discs, and HiSpec 4 pots on the front. with the sierra MC the pedal is very hard with next to zero 'feel' i have to really push the pedal to brake hard. its not bothered me much but since im changing out the cylinder i may as-well fit something better


SJ - 11/9/17 at 07:56 AM

I've got a Fiat 124 19mm mc. It works really well but the mounting holes are in a different orientation to the Sierra MC. That meant making an adapter plate to mount it to the bulkhead. If the Fiesta has the same hole alignment as the Sierra it would make swapping it over a lot easier.

Stu


flanders - 11/9/17 at 08:10 AM

Thanks Stu.

if the mounting holes are different orientation could you not just have drilled 2 new holes rather than make an adapter plate? or am i missing something

quote:
Originally posted by SJ
I've got a Fiat 124 19mm mc. It works really well but the mounting holes are in a different orientation to the Sierra MC. That meant making an adapter plate to mount it to the bulkhead. If the Fiesta has the same hole alignment as the Sierra it would make swapping it over a lot easier.

Stu


SJ - 11/9/17 at 08:40 AM

quote:


posted on 11/9/17 at 08:10 AM
Thanks Stu.

if the mounting holes are different orientation could you not just have drilled 2 new holes rather than make an adapter plate? or am i missing something
quote:
Originally posted by SJ
I've got a Fiat 124 19mm mc. It works really well but the mounting holes are in a different orientation to the Sierra MC. That meant making an adapter plate to mount it to the bulkhead. If the Fiesta has the same hole alignment as the Sierra it would make swapping it over a lot easier.

Stu




Good point - It was a while ago, but from memory I think also the bore of the hole needed in the bulkhead was a bit smaller as well, so the holes would have been right on the edge of the metal.

This didn't strike me as being strong enough & putting the adapter plate in place gave it a lot more strength.


Stu


flanders - 11/9/17 at 08:49 AM

ah yeah i get you! good point


flanders - 11/9/17 at 10:49 AM

Does anyone know the part umber or have a link to the correct Fiesta cylinder?


Dick Axtell - 11/9/17 at 12:02 PM

quote:
Originally posted by flanders
Does anyone know the part umber or have a link to the correct Fiesta cylinder?

So far as I've been able to establish, the Ford Fiesta mcyl (19.0 dia) is 74066105 (Girling), 6067715 (Ford), or MBM758 (Moprod). There may be other equivalents.


flanders - 11/9/17 at 12:05 PM

quote:
Originally posted by Dick Axtell
quote:
Originally posted by flanders
Does anyone know the part umber or have a link to the correct Fiesta cylinder?

So far as I've been able to establish, the Ford Fiesta mcyl (19.0 dia) is 74066105 (Girling), 6067715 (Ford), or MBM758 (Moprod). There may be other equivalents.


thanks mate, does this look right then .... https://www.buycarparts.co.uk/metelli/7724702
Genuine Delphi Brake Master Cylinder LM36199

[Edited on 11/9/17 by flanders]


flanders - 11/9/17 at 12:10 PM

The 4 outlet MC's im assuming are for cross circuit brake systems with 50/50 split? will i be ok (bias wise) running both rear caliper from one outlet?

will the sierra reservoir fit on the fiesta MC?

[Edited on 11/9/17 by flanders]


martinnitram - 11/9/17 at 06:09 PM

You would just blank off the ports you don't need with bleed nipples, I'm not sure if the sierra res will go on the fiesta one, I lost interest in that one once I realised it clashed with my steering column.
Good shout who ever it was for mentioning the fiat 124, looking on t'bay that comes with reservoir pipe adaptors so you could run separate reservoir bowls and could mean it can be angled slightly to match the fixing holes.

Any reason why you shouldn't angle a master cylinder ??

Sorry op for jumping on your thread, but mine was going nowhere.


flanders - 11/9/17 at 06:17 PM

Not a problem bud. It's all good questions and info. Good thinking with the mounting of the fiat one. Plus it looks to have 3 outlets.
Remote mounting a reservoir would be ideal. Have You seen a decent remote reservoir to use??

[Edited on 11/9/17 by flanders]


martinnitram - 11/9/17 at 06:19 PM

quote:
Originally posted by flanders
Thanks Stu.

if the mounting holes are different orientation could you not just have drilled 2 new holes rather than make an adapter plate? or am i missing something
quote:
Originally posted by SJ
I've got a Fiat 124 19mm mc. It works really well but the mounting holes are in a different orientation to the Sierra MC. That meant making an adapter plate to mount it to the bulkhead. If the Fiesta has the same hole alignment as the Sierra it would make swapping it over a lot easier.

Stu



Hi Stu, what calipers are you using this M/C with, ( I'm running wildwood powerlite 4 pots ) just trying to gauge how much improvement to expect, and did the fiat take the sierra push rod or was that altered.
Thanks
Mart.


martinnitram - 11/9/17 at 06:24 PM

quote:
Originally posted by flanders
Not a problem bud. It's all good questions and info. Good thinking with the mounting of the fiat one. Plus it looks to have 3 outlets.
Remote mounting a reservoir would be ideal. Have You seen a decent remote reservoir to use??

[Edited on 11/9/17 by flanders]


Not seen one in particular but you see loads for sale in demon tweeks and the like, I'm thinking along the lines of running two smaller bottles one for each circuit for simplicity and would be a little safer in the event of reservoir leak.


flanders - 12/9/17 at 09:52 AM

ok so ive ordered

Fiat 124 MC (eBay)
Dual remote reservoir (CBS)
Brake fluid rated hose (CBS)
M10 x 1.25 brake pipe fittings (eBay)

Hopefully I have time to try and install it this week. Im hoping i can reuse my push rod and that the MC will bolt up without having to make a plate.

[Edited on 12/9/17 by flanders]


flanders - 12/9/17 at 10:00 AM

Anyone reading this who has fitted the Fiat cylinder,
i assume the 2 ports together are for the fronts calipers and the single port towards the front is for the rear calipers?

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SJ - 12/9/17 at 10:21 AM

quote:

quote:
Originally posted by flanders
Thanks Stu.

if the mounting holes are different orientation could you not just have drilled 2 new holes rather than make an adapter plate? or am i missing something
quote:
Originally posted by SJ
I've got a Fiat 124 19mm mc. It works really well but the mounting holes are in a different orientation to the Sierra MC. That meant making an adapter plate to mount it to the bulkhead. If the Fiesta has the same hole alignment as the Sierra it would make swapping it over a lot easier.

Stu


Hi Stu, what calipers are you using this M/C with, ( I'm running wildwood powerlite 4 pots ) just trying to gauge how much improvement to expect, and did the fiat take the sierra push rod or was that altered.
Thanks
Mart.



I'm running standard Sierra brakes. The push rod I have is home made but it swapped over fine. It made a big difference to pedal feel.

Stu


martinnitram - 12/9/17 at 04:31 PM

quote:
Originally posted by flanders
ok so ive ordered

Fiat 124 MC (eBay)
Dual remote reservoir (CBS)
Brake fluid rated hose (CBS)
M10 x 1.25 brake pipe fittings (eBay)

Hopefully I have time to try and install it this week. Im hoping i can reuse my push rod and that the MC will bolt up without having to make a plate.

[Edited on 12/9/17 by flanders]


Ive ordered one as well.
Not ordered the reservoir yet though, had another thought and mine has the fluid level switch which id try to keep, so ill get it in bits first and see if I can re fit the sierra res.
Hopefully well both have decent brakes by the end of this !


martinnitram - 12/9/17 at 04:34 PM

quote:
Originally posted by SJ
quote:

quote:
Originally posted by flanders
Thanks Stu.

if the mounting holes are different orientation could you not just have drilled 2 new holes rather than make an adapter plate? or am i missing something
quote:
Originally posted by SJ
I've got a Fiat 124 19mm mc. It works really well but the mounting holes are in a different orientation to the Sierra MC. That meant making an adapter plate to mount it to the bulkhead. If the Fiesta has the same hole alignment as the Sierra it would make swapping it over a lot easier.

Stu


Hi Stu, what calipers are you using this M/C with, ( I'm running wildwood powerlite 4 pots ) just trying to gauge how much improvement to expect, and did the fiat take the sierra push rod or was that altered.
Thanks
Mart.



I'm running standard Sierra brakes. The push rod I have is home made but it swapped over fine. It made a big difference to pedal feel.

Stu


Thanks, should make a big difference to my brakes as well then.


davidimurray - 13/9/17 at 08:39 AM

Been thinking about doing the same. Would be really interested in some feedback on how you get on and photos of the finished installations.


martinnitram - 18/9/17 at 05:57 PM

quote:
Originally posted by davidimurray
Been thinking about doing the same. Would be really interested in some feedback on how you get on and photos of the finished installations.


Ive made a start.

This is a fiat 124 master cylinder replacing ford sierra

Fitted to the bulkhead with a spreader plate to cover the bigger centre hole left by the sierra item.
Existing sierra push rod went straight in nicely.

First cock up, I didn't take M/C to auto suppliers before fitting it and try some male fittings in the threads, along with the brake light switch as the sierra items don't fit.
Was planning of doing new flares, and reusing the fittings.
I think they must be metric being European M/C

Need to remotely mount the reservoir some how, the sierra one actually pushes into the holes in the fiat but its not an exact line up and you cant get the pipes in anyway as they go in the top.

A few pictures here https://www.facebook.com/raw.striker.12


martinnitram - 18/9/17 at 06:07 PM

quote:
Originally posted by SJ
I've got a Fiat 124 19mm mc. It works really well but the mounting holes are in a different orientation to the Sierra MC. That meant making an adapter plate to mount it to the bulkhead. If the Fiesta has the same hole alignment as the Sierra it would make swapping it over a lot easier.

Stu


What reservoir did you end up using stu.
Did you manage to re use the sierra or use after market.

I'm hoping to re use my sierra one to have the fluid level warning light working, not worked out how yet though.


flanders - 9/10/17 at 11:14 AM

Finally got round to fitting the Fiat unit.

fairly simple job, much better with the remote reservoir.

new cylinder
second hand reservoir
new brake pipes and fitting (different thread for the fiat MC)

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Had a quick run out last night, much much better pedal feel although i think ive still got some air trapped, probably in the rear calipers

[Edited on 9/10/17 by flanders]


jps - 9/10/17 at 11:23 AM

Sierra res can be reused, Voucht on the Haynes forum (am here?) did a template for an alu mount to hold it in the right orientation for a 7 installation (in the Sierra the m/c fits the bulkhead in such a way as it was angled upwards - so the mount compensatates for this.

I got a Mk1 cylinder as NOS from eBay a few years ago - good to see part numbers to show they are available as NNS though!

[Edited on 9/10/17 by jps]


martinnitram - 9/10/17 at 10:07 PM

Nice work, as you know I'm doing the same job, sierra to Fiat master cylinder, not had mine out on the road yet as have a few other jobs on going.

I ended up with a reservoir from kitspares who are not far from me, came with a nice alloy bracket which saved time with mounting.

Don't know about you but the bottom of the ports is a bit rough and took a real good tighten to get the pipe unions to seat in without leaking, worse one is the 2nd front brake port which I screwed a bleed nipple in to blank it off, ( you ran 2 separate lines ) its a stainless nipple so quite hard against the rough inside of the port and didn't want to seal at first.

Pedal feels better though.


CosKev3 - 10/10/17 at 06:51 AM

quote:
Originally posted by martinnitram
Nice work, as you know I'm doing the same job, sierra to Fiat master cylinder, not had mine out on the road yet as have a few other jobs on going.

I ended up with a reservoir from kitspares who are not far from me, came with a nice alloy bracket which saved time with mounting.

Don't know about you but the bottom of the ports is a bit rough and took a real good tighten to get the pipe unions to seat in without leaking, worse one is the 2nd front brake port which I screwed a bleed nipple in to blank it off, ( you ran 2 separate lines ) its a stainless nipple so quite hard against the rough inside of the port and didn't want to seal at first.

Pedal feels better though.


I wouldn't mind betting the bleed nipple has the wrong shaped seat to fit correctly?

If you look at a brake pipe fitting flared end it is nowhere near the same shape as a bleed nipple!


flanders - 10/10/17 at 08:18 AM

yeah i didn't have any issues with leaks bud. I pressure tested the system for 3 hours before filling with fluid.

Im going to re-bleed the system tonight, I think I may still have air trapped somewhere (probably rear calipers or in the cylinder) and im going to adjust the pedal so that there is a tiny bit of play between the push rod and the cylinder


martinnitram - 14/10/17 at 08:59 PM

quote:
Originally posted by CosKev3
quote:
Originally posted by martinnitram
Nice work, as you know I'm doing the same job, sierra to Fiat master cylinder, not had mine out on the road yet as have a few other jobs on going.

I ended up with a reservoir from kitspares who are not far from me, came with a nice alloy bracket which saved time with mounting.

Don't know about you but the bottom of the ports is a bit rough and took a real good tighten to get the pipe unions to seat in without leaking, worse one is the 2nd front brake port which I screwed a bleed nipple in to blank it off, ( you ran 2 separate lines ) its a stainless nipple so quite hard against the rough inside of the port and didn't want to seal at first.

Pedal feels better though.


I wouldn't mind betting the bleed nipple has the wrong shaped seat to fit correctly?

If you look at a brake pipe fitting flared end it is nowhere near the same shape as a bleed nipple!


Ive now swapped the bleed nipple for a brass bung, and yes there is a noticeable difference in the shape.