• Hi Guest!
    If you appreciate British Car Forum and our 25 years of supporting British car enthusiasts with technical and anicdotal information, collected from our thousands of great members, please support us with a low-cost subscription. You can become a supporting member for less than the dues of most car clubs.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Master Cylinder Question

Share this page

bugedd

bugedd

Jedi Knight
Country flag
Offline
My bugeye has front disc conversion with an aftermarket Moss master, which I think is 7/8", the only thing they offer. When putting it in, I recall the push rods from the old system being too short. After reading at Gerardsgarage.com about the correct 3/4" master working better for the disc conversion, I saw that the 3/4" bore used shorter push rods. So I am thinking the master that I have sitting in the shed may be the correct one, and I should check that out and perhaps use it. So first, how do I identify it as the correct unit? And second, if it is the proper unit, who rebuilds them?
 
We had our BE master cylinder rebuilt and sleeved (to match the stock front drums and the Rivergate clutch kit) by Sierra Specialties https://www.brakecylinder.com/index.htm Ours was one of the 'Roadstar' semi-rebuilds (installed about a dozen years back). There are other sources that I'm sure others will also reference. If/when I get to the second BE project, I'll go with Sierra again and ask them to match the front discs and Rivergate clutch that we'll be installing.
Doug
 
Doug,

I have been doing business with Joe (Sierra) for about 14 years now, and there isn't anyone out there who does better work or stands behind his product more than he does. He's done dozens of MC's for me over the years.

The tandem Spridget master cylinder, as it's available through Sierra, is a product that I developed with Joe's help and expertise in hydraulics. He's an all around great guy and not something I could not have done without his willingness to "lend me an ear". We've shipped these MC's as far as South Africa and Australia, including quite a few members on this and other forums, all with 100% satisfaction.

Quote from Joe's web site:

"Our friend and customer Gerard Chateauvieux provided the initial impetus for this program, and has written his own description of the project on his website. Gerard's site, Gerard's Garage , is an excellent resource for owners of Little British Cars, especially the MG Midget and Austin-Healey Sprite."
 
I had him resleeve/resize my cylinder in 2007/8, and it has been performing flawlessly.
 
Bugedd: The bore of the master cylinder should be marked on the side. It will be shown as a fraction i.e. 3/4. Gerard's site and recommendations look like a good place to go if it needs work or if you wnat to resize a 7/8.

Kurt.
 
I will also recommend Sierra! No problems at all since he redid my master!
BillM
 
I wonder if its possible to rebuild the cylinder myself? I can't read the size on the side of it and it looks like the cylinder was wire wheeled and it took it off. But I pulled a piston and its 3/4.
 
It should be noted that for anyone with a 3/4" bore MC, if your pistons are original (See comparison chart on my web site) and in good condition, you will save yourself the $80 for new pistons. This does not apply to <span style="font-style: italic"><span style="font-weight: bold">Roadstar</span></span> master cylinders and the substituted inferior, oversize pistons. The <span style="font-style: italic"><span style="font-weight: bold">Roadstar</span></span> master cylinder are very prevalent in the 3/4" size since 3/4" replacement master cylinders were not available for over 20 years, and not until I came up with this solution with Sierra. Under the above circumstance, you pay the regular sleeving rate on 3/4" MC's
 
Question on the master, how much less pedal effort is felt for both the clutch and brake system when swapping over to the 3/4 bore?
 
Mathematically, it's about 33%. Your perception may vary. You won't perceive this the same way on the clutch as the brake. The clutch side will have better "feathering" and be less "switch-like".
 
I see, so more progressive on the clutch. Thats what I'd like. I'll have to send off my master to Sierra soon to get it rebuilt. The crappy part is bleeding everything after :frown:
 
I just spoke with Joe, and he sends the masters back unfinished. Any thoughts on how to properly finish them so that brake fluid won't eat up whatever is on it?
 
bugedd said:
I just spoke with Joe, and he sends the masters back unfinished. Any thoughts on how to properly finish them so that brake fluid won't eat up whatever is on it?
Click to expand...

I just used clear coat but then I Also used DOT5 fluid. Some of the polishes leave a protective finish.
 
The make some special paints (VHT/Caliper paint) that work better, but may not be 100% resistant. A catalyzed paint would probably hold up best. Some people powdercoat, which seems to hold up well. If you powdercoat, you need to have it done <span style="font-style: italic">first</span>.

When I first began doing this with Joe, we had cad plating as an option. However, depending on how deeply rust saturated the MC was, the plating could sometimes come out stained, so results were inconsistent and we abandoned doing that. I have one left that is cad plated. It's too bad because is was a nice way to go. You can see a few examples on my web page.
 
I would have loved to have had mine cad plated.. Got mine back from Joe a month or so ago. Looks nice, and I can't wait to use it!
 
Unfortunately, results were inconsistent. Most were fine and looked great, but Joe being the kind of guy he is, would end up paying to have the so-so ones done twice (at his expense). It just became an impractical thing to keep doing.

Glad to hear you're pleased with it. You'll be even happier with it's performance.
 
Back
Top