MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Recommendations

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 Midget and Sprite Technical - Conrod small end bushes

My 998cc has 1098 rods and a few years back one of the small end bushes started rattling. It seems to be impossible to buy the bushes so I had to press one out of a spare rod and use that (my rods are lightened so I can't change them now). Now one or more of the other small ends are rattling. This time I would rather have a new bush reamed to the correct size - the rods are over 50 years old of course. I can make the bush on the lathe and use a hand reamer, but what is the correct material? Some kind of bronze I'm sure, but would Oilite be OK?
L B Rose

http://www.psautoparts-store.co.uk/download/Classic%20Car%20Parts%20Catalogue.pdf.1d922d0a4098178830f8db93f016cb3e


part no rb4550 ( plentty in the states, so should be over here too, maybe mini ?)
mog

I know on the couple of times I've had this done the shop sent them to a specialist for honing rather than reaming. I would not chose Oilite as it is sintered and porous so could break up due to the loads involved.
David Billington

Why not simply have the rods re-bushed and reamed to size by your local machine shop? It's not expensive and most machine shops have the kit to do a perfect job matched to your existing pins or to new pins. As far as I know, the bushes are not in short supply and machine shops tend to have loads and loads of sizes in stock or available very quickly.
Nick Nakorn

My thinking was that it would be quicker and more convenient to do this myself as I have the equipment. There is no machine shop within 20 miles! But I'll certainly see who might do it.
L B Rose

Just found they are back in stock at AH Spares - only £1.75 each!
L B Rose

OK the new bushes have arrived. I was just looking at the BMC service manual which says:

"The piston/gudgeon pin and connecting rod/small end bush can only be obtained as assemblies. Therefore, under no circumstances should the small end bush or gudgeon pin be renewed separately".

This is rather unclear - renewed separately from what? From each other or from the rod or piston? I can't see any problem if the bush is properly honed to fit whatever pin you have. What does this mean?
L B Rose

I think it means that the average garage shouldn't attempt to knock the old bush out, put a new one in and expect it to be OK.

Not a problem for an engineer who knows what they're doing.
Dave O'Neill 2

This thread was discussed between 19/08/2015 and 22/08/2015

MG Midget and Sprite Technical index

This thread is from the archives. Join the live MG Midget and Sprite Technical BBS now