MG-Cars.info

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

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 - Differential filling plug

Quick tips appreciated on how to remove a totally solid diff oil filling plug. Tried a half inch square socket with much leverage - no joy, but it does not help when I cannot obtain much purchase with the socket - a very shallow and rounded plug recess....
Oggers

IIRC the square socket is tapered and you can get spanners which have tapered square pegs for the job. Never needed one myself but I know they're are available. Possibly some timber between the tank and drive to stop camming out but that doesn't always help. One time I gave up with a damaged hex cap screw and went down the pub, the next morning I took a die grinder to the cap screw head, removed it and the remains came out with my fingers.
David Billington

Oggers,
I found a large diameter bolt in my "useful stuff box" and cut and ground the bolt shaft ito a slightly tapered squared shape that fits snugly into the drain plug. It is cut shott so that the bolt head is close to the drain plug. I can then use a ring spanner or a socket with a long breaker bar. But the one that worked best was using it with an air impact wrench. The hammer action shifted it easily.
GuyW

Weld a nut to it.

Heat breaks the rust bond and far easier to use a socket!
Karl Bielby

I've found a 3/8" ratchet without a socket is good.

If there is enough thread showing a pair of Stilsons work ok but may damage the threads somewhat, but the outer threads are not important anyway.

Rob
MG Moneypit

The threads are BSP so if you damage the nut you can get a variation in brass or steel from the plumbers merchant. Perhaps one with a raised square or hexagon. Refit with PTFE tale to stop 'locking' and leaks.
Alan
Alan Anstead

David,
the taper square peg on my multi-spanner tool was useless, I had to cut it down a bit to get good purchase but even then the shape of that tool made it difficult to get extra leverage.

It's IIRC is a Draper cast type tool.
Nigel Atkins

Mark,
there was a recentish thread with the same problem, some of the same answers plus a few more.

3/8" ratchet bar worked for me plus loads of PlusGas (not WD40) despite the thread on plug.

The replacement plugs tend to be with 3/8" hex now, buy two ready for drain plug issues (or better still replace the axle oil now, blow the expense, now sit down as the thought of the cost has probably made you dissy).
Nigel Atkins

You don't want to apply too much leverage as the diff backplate isn't that thick and is prone to surface rusting. You could tear it if you get out the 3ft breaker bar.

As noted, welding on a nut will undo most stuff but for an axle the location is tricky. I would drain the oil, wirebrush to remove crud, then give it a good bit of heat (dull red), squirt with your favourite releasing oil and retry when it's cool enough to touch.

Be careful with proximity to fuel tank and line, obviously.
AdrianR

Chemical and patience has always worked for me IIRC.

Clean area, liberal spray of PlusGas leave to soak as long as possible, try to tighten (yes I know, if it don't it don't) then try to loosen with whatever tools are required. If it doesn't work first time try again, spray leave at least overnight and try to (tighten and) loosen again. If necessary repeat again.

I know it's not macho or engineering or mechanically inventive but it works with the least amount of physical involvement (which is always my aim) and to me exotic equipment.
Nigel Atkins

Any progress? If you're going to try releasing agent maybe use some putty or similar to make a bowl shape around the plug so it can soak in rather than running off.
AdrianR

Stilsons eventually got it. A little more leverage I feel. Good news is that it was full of oil, so tick that one off.
Oggers

This thread was discussed between 18/06/2018 and 22/06/2018

MG Midget and Sprite Technical index

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