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green96v4Posted - 14 Oct 2017 : 14:57:50
So the weather is closing in on me in (not so) sunny Ontario, so I've pulled the car off the road

I noticed over the summer a tiny leak from the Brake Master Cylinder (which has done a wonderful job of stripping the paint at the back of the engine bay!!)

I've pulled the Cylinder off the car and taken it apart, my first though was the "Specialist" I sent it off to had not replaced the seal/rubbers, but turns out the rubbers are all new and fresh

Difficult to see on the images, but the piston has some scoring and a pit right where the seal seats. Cylinder lining looks/feels ok (from what I can see/feel with my little finger - not that scientific I know!!)

So the search is now on for:

New Piston (SAAB # 7348642)

Or a whole new unit (SAAB # 7356561)

Or a compatible Lockheed Brake Master Cylinder from any other Marque that might have used it. Triumph seem to have used very similar units on the Stag, but the Lockheed part #'s are different and from what I can see SAAB used 13/16" and Triumph used 7/8" (also the locating holes for the threaded servo attachments are in different spots, mine are 12 and 6 o'clock whereas the Stag's are more 2 and 7 o'clock)

Numbers on the side of my Lockheed unit are 3212 830 0 13/16

Mine is the '69-'70 earlier servo unit and if I just can't find a replacement would the later unit fit? (the whole thing inc servo or just the MC)

Has anyone discovered another Marque that used the same unit?

If I just took off the whole unit (inc servo) would a full replacement for a Stag fit? had pistons listed in their NOS but they've been sold, they've said they are working on a replacement for this particular MC, but will know in the coming weeks

Saabklubben only have seal reapir kits (which I know John-Saab also does) but I don't think it's the seals

Any help/insights/tips gratefully received

Thanks in advance
11   L A T E S T    R E P L I E S    (Newest First)
green96v4Posted - 17 Oct 2017 : 21:51:08
Cool thanks Melle
mellePosted - 17 Oct 2017 : 21:10:42
I looked at your photo again and remembered it's one of the other types I have... Will look anyway and post some pics, perhaps the internals are the same.
green96v4Posted - 17 Oct 2017 : 18:20:22
Thanks Melle, won't be too late for me, winters are long and salty here, so I'm not SAABing anywhere until April....

I stand to be corrected, but the 96 wasn't ever imported to Canada, they started with the 99 (US got it with the 2// and then the 1.7L)
mellePosted - 17 Oct 2017 : 16:28:23
I'll have a look at what I have next time I'm in the workshop. That'll be around Christmas, probably a bit late for you, so just for the record.

Derek, does he refer to two stroke or V4 stuff? V4's don't have rear brake proportioning valves as far as I know and I'm pretty sure variations of the Lockheed bmcs used on V4s were pretty common in Europe. I appreciate that may be very different in the States/ Canada.
green96v4Posted - 17 Oct 2017 : 16:01:25
Thanks Derek
I'd have to take a look at the bills to see who did the rebuild (someone out of C&SC Magazine, that seemed to be my go-to when I didn't know where to go for things like this and most of these "specialist" rebuilds I did when I was still on that side of the pond) They also did the rattling caliper I have, so again, not the best choice on my part!!

The guy who rebuilt my gearbox has offered to remake the piston (he's a T&D Machinist, so can make most things!) I was just hoping the piston was used somewhere else (like the Mini rear cylinders

Melle I've had a quick look online at Victor/Viva BMC's but they look more like the older 2 stroke/pre servo BMC's

The search goes on....
DerekPosted - 17 Oct 2017 : 13:35:10
Who did you get your MC rebuilt by? WhitePost good and Apple not very good/consistent by reputation. Some relevant pots recently on the Yahoo Saab forum.
"Past experience prompts me to not recommend Apple for anything I'd choose to keep. Frequent failures on components serviced or restored by them in the past has been frustrating to say the least. White post is a far FAR better choice!One problem with our Saab master cylinders is a reliable source for rebuildable cores and cores strictly for parts. All my brake master cylinders from parted out cars went to Chip (Lamb)who in turn offered them as both rebuildable cores and parts units to white post. Even more problematic are the rear brake proportioning valves. Be careful choosing where you ship unobtanium to." Chuck Christ (real name by the way)
green96v4Posted - 14 Oct 2017 : 18:03:57
Yes I learnt the hard way about British BSP/NPT/Metric brake lines as the local parts store here supplied me with Metric lines (bent and formed a bunch of them before realizing they wouldn't connect, and when I took them back they thought SAAB was European, therefore must be metric. Not sure what uses metric, Japanese maybe?)

Thanks Melle I'll check out Viva/Victor MC's and see if they're the same
mellePosted - 14 Oct 2017 : 17:39:36
Most pipe fittings in Europe are BSP (British Pipe Thread; Whitworth based, 55 degree threads), only very few are NPT (National (=American) Pipe Thread, 60 degree threads). I've never seen metric pipe threads, but I don't doubt they exist.

I have a couple '60/'70s Vauxhall (Viva? Victor?) master cylinders in the workshop, from memory they are externally identical to what's on our Saabs, but I'm not sure about the internals, never cared to take them apart. They came from LHD Vauxhalls and I compared them to LHD Saab bmcs.
andydeans3Posted - 14 Oct 2017 : 17:06:05
I think you'll find that if it's a Lockheed cylinder, it will have imperial fittings. I doubt Lockheed made two different sizes of threads on identical Master Cylinders. (though willing to be corrected)
Even the French use imperial measures for a few odd things like, inches for wheel diameters, inches for push bike frame sizes, feet for lengths of pleasure boats.!!
ie Just because something comes from a Renault, doesn't mean it's all metric.
I remember once being in a DIY store in France and picking up a brass garden hose valve labelled "13mm". Embossed on the body of the valve was 1/2. ie it was a 1/2" valve, with 1/2" NPT threads, simply labelled with the nearest , full number, metric equivalent.
Had fun trying to tell one of the young assistant that it was a half inch valve, while he insisted it was a 13 mm valve. He had no idea what the 1/2, embossed on the valve, meant.(I think because they don't learn fractions in school in France)


1978 LHD SAAB 96
1978 MGB Roadster
2008 LHD "Classic" Renault Twingo
green96v4Posted - 14 Oct 2017 : 15:46:42
interesting, I wonder if he had to modify the brake lines (I'm assuming Renault must be metric)
mellePosted - 14 Oct 2017 : 15:35:11
Spoke to a chap at Swedish Day who fitted a servo + bmc from a Renault Kangoo.

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