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MG MGA - Brake bleed screw problem

For the last couple of weeks one of my rear brakes has been leaking fluid through the banjo connector and/or the bleed screw. It's only a slight drip every so often, but clearly something that needed sorting, so this morning I took delivery of new copper washers for the banjo and a new bleed screw. My problem is that the new bleed screw is shorter than the old one, by about 2mm, and runs out of thread before it locks (see picture attached). I have now put the old one back, using plumber's PTFE tape, and everything seems OK at the moment, but I'll obviously be keeping an eye on it over the next few weeks just in case.
I'm just curious to know if anyone else has had this problem?

Robert Sinclair

Nothing new - many repro parts are either "universal" but don't actually fit or there are different specs between say MGA and MGB and the parts man has chucked them all in the same bin!

You should not need tape on the threads - the seal is made on the conical end of the bleed screw.
Chris at Octarine Services

Where did you buy the bleed nipples from?
I bought new ones recently from Moss that seem fine, though perhaps I need go and check!
Graham V

I bought it from MGOC. Moss lists 2 versions of bleed screws, Whitworth and UNF, whereas MGOC only lists the one that I bought. Maybe that's the problem?
Robert Sinclair

Having fitted a servo I found it very difficult to get a seal with my new Moss bleed nipples into the inner RH side of the front caliper. The torque required to get a seal was extreme.

I have some old and tatty bleed nipples with copper noses to give a softer metal seal. Are these still available?

BTW, the Moss nipples I bought were longer than the originals.

As Chris says, anything goes.


Bolney Coupe

The BSF fittings were only used on fairly early production cars.
D Rawlins

The OE nipples were actually copper plated against corrosion - most of the copper disappears over the years just leaving the plating protected at the end of the nipple.

Generally speaking I prefer to use original parts - even it they look a bit tatty - it's the function that is important rather than the looks!
Chris at Octarine Services

This thread was discussed between 01/08/2017 and 03/08/2017

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