Master cylinder

[califkid_66]

Had a small leak where the pushrod enters the master so I decided to rebuild it
I’m trying to find a rebuild kit with 0.70” primary and 0.66” secondary
I found rebuild kits but they don’t mention the sizes
Any suggestions or part numbers for rebuild
 Thanks!

[BDA]

White Post Restorations should be able to rebuild your M/C and they will also sleeve the bore in brass. I was happy with the job they did on my M/C and rear calipers. https://whitepost.com/#hometop

[jbcollier]

Bores and pistons wear and corrode.  Usually there are deep corrosion pits deep in the bores.  Plastic reservoirs also deteriorate over time.  I believe you can finally get new reservoirs now.  Your options are to sleeve & rebuild or to replace.

After 35 years in the field, I only replace with new.  I’ve never had a “bad” new TRW master cylinder but I have quite a few new knock-offs fail.  Rebuilt masters? I would say a 50% failure rate either right away or within the first year of use.  You can’t get an exact new master but the Triumph one can be easily adapted and performs well.

[Clifton]

A long time ago it was cheaper to buy rebuild kits for master and slave cylinders locally. Now, I agree with the buy new.

If you want to make a bracket, Wilwood sells a 5/8 that would work. 5/8 would give better pedal feel with a little more travel.
 https://www.wilwood.com/MasterCylinders/MasterCylinderList?group=Tandem%20Master%20Cylinder%20(TM1)

[califkid_66]

Thanks for the replies
I think the best option for me is to put a new one

[califkid_66]

I was looking at the cardone 13-1777 it looks a lot like the original comes with a nice square reservoir
Brake lines same side
Or the triumph spitfire mc tilted reservoir brake lines wrong side
Both need some fabrication not sure witch one would be better

[bjthomp]

Have you looked for an MC at Moss Motors? They carry a large selection of different MCs used on British cars and I believe they're all new, as opposed to Cardone, which is a rebuilder. Their search function leaves a lot to be desired and requires patience but keep looking and eventually you'll most likely find a direct replacement.

[jbcollier]

Don't go Cardone!

Go Triumph Spitfire 0.70 tandem. A genuine one from Girling TRW.  Not cheap but worth every penny.

[califkid_66]

Got it !! So the only modification is the brake lines but what about the reservoir do I need to change it
Or it is ok ?

[jbcollier]

It works just fine as is.

[califkid_66]

I am going to put the trw mc small cap 0.70” on my Europa
But I still inquired about sleeving

For lotus Europa 1970 s2 master cylinder sleeving
245 plus s/h it’s in us
Turnaround about 2 weeks

This is from BDA ‘s  link white horse

[RoddyMac]

BPNW lists the TRW cylinder for a bit less than Moss:

https://bpnorthwest.com/triumph/spitfire/brakes/brakes-control/brake-master-cylinder-spitfire-76-to-80.html

[Grumblebuns]

A word of caution on using the aftermarket Spitfire MCs. The original Spitfire MCs had Imperial 3/8-24 threads on their output ports. I don't know if Triumph ever changed the threads during the production run but the current aftermarket Spitfire MCs have metric M10-1.0 threads. The danger is that the 3/8-24 tube nuts will fit very loosely in the ports and when attempting to torque down on the tube nuts you run the risk of stripping the threads most likely on the MC. Conversely, the M10-1.0 tube nuts will not thread into a 3/8-24 threaded hole.
 

[jbcollier]

Triumph switched from imperial to metric brake line nuts in the late 70s.

[califkid_66]

I know I have to fabricate new brake lines I just have to figure the best way to get it done
I could make custom or take existing lines like 10 m and put a fitting that goes metric to imperial
I’m planning to do like in the picture

Found fittings so the plan is to get 12 inch 3/8 imperial line and put female to male 3/8 to m10
Fitting on the master for one of the lines it think this is the best way