diff drain plug

[thomas]

I read of people putting a drain plug in the diff housing but they seem to be using a tapered thread. Is there something wrong with just using an M8 bolt and copper washer. I know it's a little small but surely it is big enough to let the crap drain out,albeit a little slowly and most of us would have a tap of this size lying around,plus the fact it's easy to drill for this size?

[CharlieB]

You would need a machined surface for the washer to seal against. Why not just use an engine/gearbox tapered plug? The thread in the casing can be parallel.

[thomas]

Charlie,I don't have one handy. There is an area at the bottom of the diff ,sort of a blank spot where there should be a drain plug. If this was drilled and tapped and the area dressed with a file,do you think it would be flat enough for a copper washer to seal against? I have some Minors about and could use a plug out of box or diff of these but I'd need to buy a large enough tap and is the tap thread different for a taper plug or is the difference in thread (as opposed to an ordinary bolt -nut) on the plug. Also I wouldn't be keen on it protrudeing at the bottom of the casing for obvious reasons.

[GT6 M]

No , , you will get away with the finnish thats there,
if its a little too ruff, you can always give it a gentle file,

use a good thick  red fibre washer, and drill it oot to 1/2 inch,
put a drill inthe end of the bolt, and you can then put a hole in it

and then put a small magnet in it, to catch all the sheeite, that would normally just go round and round

wearing every thing oot

I got this, and it ..never leaks oil

also put a gearbox drain plug in the filler  hole, then you got two ..sheeite.. catchers, :) :) :)
or you can drill it oot to take the g/box plug,

this way you will have the Magnet already there  :) :)

[ same plug, also fits engine sump, ] :) :)

regards marcus

[thomas]

Thanks Marcus for your advice. I'll give it a try as I think some shite got in through the holes when changing the spring.

[GT6 M]

its easy to drill when in situ, just put a pilot drill thru first,

then follow with a size for the tap,

put a magnet on the drill, it will keep the swarf to it,

should be able to hire a tap of an engineering firm , if you no got one, or looook on car boots,!!

ten a penny on there

Marcus

[junkuser]

To seal drain plugs that rely on a washer rather than a taper, you can use an "O" ring and metal washer.
The "O" ring should have an ID to suit the threaded section of the plug.
The washer should be thinner than the section of the"O" ring with ID to fit over the OD of the"O" ring.
This will seal on an imperfect surface and does not require the plug to be overtightened.
The "O" ring should be replaced whenever the plug is removed.

[thomas]

sounds good too.

[Mj17]

Or you can do it the easy way by spending £6.89 at Machine Mart - http://www.machinemart.co.uk/shop/product/details/cgg500-500cc-oil-suction-gun

With a bit of jiggling and poking you can get the pipe down to the bottom of the diff. and just suck all the old oil out before using the same tool to easily push the new oil in.

[harvey]

junkuser wrote:

To seal drain plugs that rely on a washer rather than a taper, you can use an "O" ring and metal washer.
The "O" ring should have an ID to suit the threaded section of the plug.
The washer should be thinner than the section of the"O" ring with ID to fit over the OD of the"O" ring.
This will seal on an imperfect surface and does not require the plug to be overtightened.
The "O" ring should be replaced whenever the plug is removed.

That sounds like a near perfect description of a "Dowty" washer, which can be bought at your local hydraulics supplier for a very reasonable price.

[99176]

If you fit a drain plug be ready to turn up a doughnut to fit your jack, so that you're not jacking up under the plug.