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Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Bolt and thead primer

I have had British cars in the past and have a '53 TD with the most aggravating mixture of Whitworth, metric nuts and bolts, bolt threads, engine/radiator fittings that don't fit anything else on the planet.... (but I'm keen for the challenge)

What's the scoop on a 58 A? All metric? A sprinkling of SAE?

I prefer to use stainless where I can, esp under the hood.

Is there a list of sizes/applications available? IE: body to frame bolts, heater box to body, brake MC, etc.
MAndrus

Almost everything is UNF, with a little UNC on some stud ends and the gearbox casing. Fuel system is Whitworth, and many screws in the electrics are 2BA or 10-32. There shouldn't be any metric threads at all.
dominic clancy

Your TD uses French Metric on the engine, but nowhere on the chassis itself. Everything on the car other than what is in and around the engine block is British thread.
Steve Simmons

There's a list of nuts & bolts on the website of Steve Gyles: http://www.mgaroadster.co.uk/Technical_Information/MGA%20Nuts%20and%20Bolts.pdf

I also have a similar list on two Excel files, but I forgot where I found those ;-(
Rutger Booy

There's a list of nuts & bolts on the website of Steve Gyles: http://www.mgaroadster.co.uk/Technical_Information/MGA%20Nuts%20and%20Bolts.pdf
Rutger Booy

Of course, spark plugs are metric!
Art Pearse

Link isn't good. 404.
MAndrus

Here's a pretty good list. http://www.mgaroadster.co.uk/Technical_Information/MGA%20Nuts%20and%20Bolts.pdf

Jim Cheatham
JL Cheatham

And coolant taps and fuel pipe fittings are BSP....
dominic clancy

Windscreen screws are 2BA
Art Pearse

Sorry if this is something that you have already considered but worth a mention anyway. Don't forget that standard stainless steel setscrews will probably not be as high in tensile strength as the original steel ones.
Probably be fine for fixing body panels etc but not strong enough for use in suspension and engine parts.
Colyn
c firth

Inside the hood body to chassis, heater box, carb to manifold, fender to body, hood hing to hood, etc.
MAndrus

As a general rule, stuff on the MGA that was built by MG tends to be SAE fasteners. Ancillary systems supplied by vendors (fuel, electrical, etc) tend more towards the British standards. Barney has a lot of info on thread forms and fasteners on his site, and John Twist has some good videos that touch on the subject, as well.

Stainless can be great, but you have to be careful. Stainless fasteners tend to be softer than standard steel bolts, so you don't want to substitute stainless in applications requiring high strength, and where you have to thread stainless and carbon steel fasteners together, anti-sieze lube should be used to prevent galling. And using stainless fasteners in aluminum parts is often a bad idea, because the Al in that relationship is anodic and tends to go away. Better to replace carbon steel fasteners ever so often, than to corrode the underlying parts.

-Del
D Rawlins

Del, it's stainless to stainless that galls, not ss to cs.
Art Pearse

Crap. Google reveals that you are indeed correct. A few years ago I was using a lot of stainless fasteners on a project, and it appears I misunderstood the directions I read at the time, which wouldn't be so bad (truck hasn't fallen apart yet), but I have been repeating my misunderstanding ever since then. That's embarrassing. Thanks for correcting me.

-Del
D Rawlins


body to chassis 5/16 unf, heater box to shelf 10-32 or 2BA (effectively interchangeable), carb to manifold 3/8 unf, fender to body 5/16 unf, hood hinge to hood 10-32, etc.
dominic clancy

Here is a good source for those difficult obscure British thread sizes. http://britishfasteners.com/
Bill Haglan

This thread was discussed between 13/09/2015 and 16/09/2015

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