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MG MGB GT V8 Factory Originals Technical - Master Cylinder Reservoir

I've been trying without success to source a new master cylinder reservoir for my 77 roadster conversion. The original is cracked (from the careless owner dropping a part on it!) and should be replaced. The reservoir is on a servo equipped car and is somewhat wedge-shaped.
Can this part be had separately or do I have to bite the bullet and buy the whole master cylinder.
Thnaks for your help.........

Your description of a wedge shaped reservoir indicates that your M/C is from a '74 1/2 thru '75 model year MGB and can be purchased from Moss Motors (part no.180-815) for about $17usd.
A rectangular shaped reservoir was standard on '76 thru '80 model years and this reservoir is not listed as available through Moss.

Will this Wedge shaped reserviour fit into the rectangular style master?. From photographs the masters appear to be the same (as does the RV8) My Rectangular style has a expoxied crack on the top, and I'd like to replace it.

I've checked with Moss. Although the part is shown separately from the master cylinder and is given a part number, Moss advises that it is no longer available. Will likely order the square reservoir.

Not sure if the wedge style and rectangular style reservoirs are interchangeable for a servo assist system but I can pass on some physical measurements from the latter, (if it helps) for comparison to the wedge style. The two supply nipples on the underside are 11/32" dia and spaced at 3.25". The reservoir attachment holes to the M/C are 23/64" dia and spaced at about 1.92" All you need is a wedge reservoir which now appears to have fallen into the Moss unobtainable category.
Surely demand for nylon reservoirs would make it attractive for a supplier but it seems that more profit is to be had from the sale of a complete master cylinder.

I had a good hard look at an RV8 the other day and its master appears identical to the MGB except that it hasn't got the second front brake line, provision is there but it has been left blank. Since the RV8 was assembled from parts on hand then it's likely that the reservior it uses comes from a rover of some kind?
Might be worth following up I think. I will post a question on the RV8 site and see if anyone knows.

This thread was discussed between 17/02/2003 and 24/02/2003

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