Morris Minor Owners Club

I am having a problem removing the diff oil filler plug it wont budge, also not sure of the correct key size

It's a tapered fit, and a number of multi-size tools are available that will fit. I recommend using the correct tool, but have been known to resort to a 1/2 drive air impact driver to remove really stubborn plugs. Don't use the type of impact driver where you hit it with a hammer - you want to just turn the plug, not risk damaging the casing. I have also seen people use mole grips to grab the exposed part of the plug, but again I do not recommend that as there is a risk if damaging the thread.

many thanks for useful information.

I got hold of a length of 1/2" square steel bar, filed one end down to be a good fit in the filler plug and then put a right angle bend part way along the bar so that I could put some force behind it but still being careful not to over tighten it. Works a treat!

What you need is one of these and it won't break the bank.
http://www.halfords.com/webapp/wcs/stor ... 55216#tab1

If its as tight as you say then first you need a tool that is a very good fit to avoid damaging the plug and then never getting it out!

Second, if you can't undo it buy (obviously) turning it anti-clockwise, put some load on it to tighten it (not too much though) and then try anti-clockwise again. This can often 'break' any corrosion etc on the threads and has worked for me in the past. Before anyone else says it, corrosion shouldn't be a problem on a diff drain plug!

My drain plug had a worn socket so I used a Halfords type multi tool.
I cut about 5mm off one of the tapered ends to allow for the wear in the plug socket then gently hammered it into the plug as tight as it would go.
I then fitted a two foot steel tube over the end of the multi tool and gently pulled back, releasing the plug.
The old plug was of course replaced with a new undamaged one.

sorry to dig up this old post - but does anyone know/point me in the direction of the correct tool for the diff oil filler plug. the link above to halfords doesnt seem to work anymore

I just found a bit of square bar in my junk box and filed it slightly till it fitted - tapped it in with a hammer then turned it with a spanner. But first I do suggest you take out the drain plug - and drain out the horrible old sludge that will be in there..... Neither plug needs to be particularly tight.

I use this 11mm square drive.
http://www.ebay.co.uk/itm/DRAPER-38322- ... SwNSxVP4Os

Regards
Declan

Aye - but it's a tapered hole in the plugs, and although that may work ok on a plug that's not too tight - it may just 'spin out' on a stupidly tight plug.....

I have changed them on my black minor to the newish allen key type which i have found excellent. I fully intend to change my other 2 minors through time.


http://morrisminorspares.co.uk/shop/pro ... 00194c0655

Here is a set with an 11mm sq key. https://www.machinemart.co.uk/p/draper- ... g-key-set/