Mk3 Spit Brake Cylinder

[jamie31888]

Hi Guys,

Having some issues with my brake master cylinder fouling the bonnet.

I have witness / rubbing marks where the bonnet rests on the reservoir 😲

Can anyone post up some pictures of theirs so I can see where i'm going wrong?

Cheers!
Jamie

[thescrapman]

Whatever that is, that isn't a mk3 brake master.

It should look like the clutch one.

Or perhaps like the clutch but a slighter larger diameter reservoir.

[Clive]

It could be an unusual one off a spit 1500 (export, and it used a mounting bracket at a different angle. You don't see them often......
indeed, here it is! http://www.ebay.co.uk/itm/Brak.....e:g:eccAAOSwiYFXGhtU

You want a "normal" type. It needs to have a bigger resevoir than the clutch one as Colin points out. And avoid anything that claims to be uprated, it will make the brakes hard and give poor feel. You want 5/8 or 0.625 bore.

[drofgum]

Jamie,
As the others have said, but the correct master cylinder would be similar to the clutch but have a taller reservoir, not larger in diameter.
                                                                                          Cheers,
                                                                                          Paul

[RobPearce]

Quoted from drofgum

As the others have said, but the correct master cylinder would be similar to the clutch but have a taller reservoir, not larger in diameter.

Is that right? I know the 13/60 Heralds had a plastic extension tube to increase the reservoir capacity of a cylinder otherwise identical to the clutch one, but my Mk3 Spit has always had a larger brake master - looks the same as a Vitesse/GT6 one. Of course, given how many non-standard bits Toby has acquired over the years, that may not mean anything. However, the drawings on the Canley site look slightly different - the brake reservoir is perpendicular to the piston, like the GT6, rather than canted-to-be-vertical like the clutch.

[JensH]

Mk 3 spit - european - has a reservoir that is larger in diameter 😎
NLA - but you can buy suitable replacements at the usual suspects

[Clive]

I thought the heralds with the extension were 1200's??
Anyway, yes, spitfires always had a larger diameter resevoir, just like the vitesse etc BUT 5/8 or .625 bore (Exactly the same those 2 figures!)

[RobPearce]

Quoted from cliftyhanger

I thought the heralds with the extension were 1200's??

I thought it was all the disc brake ones. Certainly the J-reg 13/60 I used to own had the extension... with a leak... until we put a spare (<cough>Vitesse) one on.

[Martins Stag]

I have a funny feeling my 198 Spitfire 1500 had a brake master like that from original I changed it out in 1984 as it leaked brake fluid down the sill.
I had brought the car from a Leyland garage at 3 years old with a warrantee and the garage refused to payout for the replacement brake master as I had not had it serviced with them! I don't think they would get away with that today.

Martin

[jamie31888]

Thanks for the replies all,

Can anyone please post a link to the right master cylinder?

The one fitted at the moment is a GMC224 and I know the GMC220 also doesn't fit from previous experience (see picture below).

Which master cylinder are you guys using on your mk3's?

Jamie

[DanM]

I use the gmc205 same as the clutch, the real one had a slightly larger reservoir otherwise the same. My mk2 has been using this for 26 years with no problems, just check fluid level regularly

[RobPearce]

The GMC220 should fit - it's what Canleys list

Looking again at your photo, it does look slightly as if the brake master is tilted considerably more forward than the clutch one. I don't think any of mine are like that (although Toby's missing all those bits at the moment, but I'd expect them to be very similar to the GT6)

[jamie31888]

Thanks for the replies all, I had a look in the Mk3 owners manual. There is a picture of the master cylinders.

The Master cylinder shown in the picture looks similar to this one, but at £120 its not cheap....

Is there any risk in using another clutch master cylinder?

[Dannyb]

Mine I think came from Rimmers some years back

[jamie31888]

Cheers Danny,

I notice your brake master cylinder bracket is more angled towards the car. That must reduce the height a bit.

I wonder if that bracket would work on a mk3 aswell as a 1500...

[Dannyb]

Should do

[RobPearce]

As I said a few posts up, yours looks wrongly angled. The brackets should be the same for all models, I think. Look for a spare bracket.

(It's quite possible, indeed likely, that I have a spare brake pedal assembly lying around. It's off a Herald but I think they're the same)

[nicmk1est]

if you google   triumph spitfire mk3 engine bay images come up of the engine bay area,some have the same type of res as you got,,seams the brackets angles are little different
https://www.google.co.uk/searc.....tfire+mk3+engine+bay

[Clive]

I am sure there were alternstive brackets, after all there must be one suitable for that MC?

[jamie31888]

I've found a few pictures like the one below.

The M/C is a metal reservoir one, the brackets are at the same angle as mine.

I just cant find anywhere selling that particular M/C which seems to be the right one.

[jamie31888]

Another similar picture 🤔

[Marc F]

Mine was plastic reservoir - over 30 years ago

[Hallum]

You mean like these?:



http://www.ebay.co.uk/itm/MAST.....a1gdNp7MaQPVebD1ZhjQ



http://www.ebay.co.uk/itm/TRIU.....5:g:eUAAAMXQ-3NRk~Nf



http://www.ebay.co.uk/itm/TRIU.....b:g:SngAAOSwI-BWHDj~

Cannot speak for the quality of them as I have not purchased from any of them myself. However, they seem to match what you describe. I too have a MK3. If I remember correctly, mine matches the shape of the first; the reservoir being perpendicular to the push rod.

Harry

[jamie31888]

Hi Harry,

Those all seem to be clutch master cylinders with the smaller reservoirs?

Any chance you could post a picture up of your set up?

Cheers,
Jamie

[Hallum]

Hi Jamie,

Sorry, yes you are right about the last one. The first 2 however I believe are correct. They both look to match the size of that fitted to mine, just seem to differ in the angle of the reservoir. You can see the pictures of mine below (ps. ignore the rust, its on my list ). The brake reservoir is perpendicular to the pushrod, the clutch is angled. Unsure if they are suppose to differ or if this was from the factory?





Thanks,

Harry