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Axle drain plug

Posted: Tue Oct 23, 2018 3:29 pm
by Rust bucket
Tried two or three times to stop the leak from the axle drain plug, used ptf tape and Holmar sealer still leaks. Can anyone tell me the thread size please, I thought of using a bolt with a copper or fibre washer.

Re: Axle drain plug

Posted: Tue Oct 23, 2018 6:09 pm
by philthehill
Ditch the tape and Hylomar.
Clean both the male and female threads and refit the taper plug.
The taper plug should seal with out tape and Hylomar.
If you must use a sealer use Loctite - Lock and Seal.

If required use a ESM rear axle filler/drain plug

http://www.morrisminorspares.com/rear-s ... al-p831251

Re: Axle drain plug

Posted: Wed Oct 24, 2018 8:37 pm
by MikeNash
Dear Rust Bucket,

The back axle drain is a 1/2 inch BSPT plug (i.e. it's thread is British Standard Pipe Tapered) and you can get them from a good plumber's store for under a £1. ( I got mine from Woodstock Plumbing & Heating Supplies, Andover, Hants; B&Q, PlumbCenter etc may not know what you're talking about.) See below esp the magnet in it's centre.

I Araldited in the magnet years ago and I urge you to do the same. Mine has an "Eclipse" ferrite rod about 0.5 inchs long and 0.25 inches diameter but these days you can get much stronger ceramic magnets very cheap on the interweb. Even in this poor photo you can see the metal wear bits attracted to it. Nearly everything in the axle is steel and with the bouncing about that the axle does there's not much chance of the wear particles sinking to the bottom and staying safely there so the magnet is particularly valuable.

A further thought is that you're sure the drips from the drain plug are not dribbles coming out of the front of the axle where the prop shaft connects and then running down to the drain area, aren't you?

Regards from MikeN.

Re: Axle drain plug

Posted: Thu Oct 25, 2018 8:12 am
by Rust bucket
Thanks for that, good idea to fit a magnet I've got one on the engine sump plug, no it's not from the diff seal. Not sure what you mean by tapered thread, is there no metal lip that stops the plug going right in which is what I was thinking. If so then I guess that the plug is wider at the socket end, eg. tapered :roll:

Re: Axle drain plug

Posted: Thu Oct 25, 2018 8:56 am
by MikeNash
Yes it is a "tapered thread"; a normal parallel "cylindrical" threaded plug will go right through and would depend on PTFE tape, etc to get a good seal. (I know!) If you want to know more about these curious threads, an Imperial survivor that's become an international standard then see here http://www.bspt.co.uk/
With your magnetic sump plug you'll know their value and know that if you fit one in the axle the first time you remove it you'll have a real "fir tree" of ancient rubbish attached to it. It's a real frightener!
Regards, MikeN.
PS Ditto the gear box too!

Re: Axle drain plug

Posted: Thu Oct 25, 2018 9:08 am
by Myrtles Man
With regard to the magnet-on-drain-plug scenario, why do you need to Araldite it on; wouldn't it just hold itself in place by, er, magnetism?

Re: Axle drain plug

Posted: Thu Oct 25, 2018 10:10 am
by Declan_Burns
Check the seal on the front of the differential. That could also be causing the leak.
Regards
Declan

Re: Axle drain plug

Posted: Thu Oct 25, 2018 10:13 am
by philthehill
The magnet needs to be permanently fixed into the drain plug as it own magnetic force is insufficient to retain it with all that oil swishing around inside the axle casing. If it came loose inside the axle casing and moved around with the diff you can say goodbye to the diff and wheel bearings.
The magnetically collected swarf is small enough to not be displaced by the moving oil.
You cannot have too many magnets collecting swarf in either the engine or gearbox.

Re: Axle drain plug

Posted: Thu Oct 25, 2018 12:02 pm
by Sleeper
"You cannot have too many magnets collecting swarf in either the engine or gearbox."

Slap one ( or more ) on the outside of the oil filter....

John :wink:

Re: Axle drain plug

Posted: Thu Oct 25, 2018 12:11 pm
by philthehill

Re: Axle drain plug

Posted: Thu Oct 25, 2018 3:05 pm
by Sleeper
Yes, but as for the " Fuel Economizer" :lol:

John :wink:

Re: Axle drain plug

Posted: Thu Oct 25, 2018 3:13 pm
by Nickol

Re: Axle drain plug

Posted: Thu Oct 25, 2018 6:58 pm
by Trickydicky
Nickol wrote: Thu Oct 25, 2018 3:13 pm Cheaper one....

https://www.ebay.de/itm/Priopa-Ol-Boost ... :rk:1:pf:0
An even cheaper method is use the magnets from a failed hard disk drive and as belt and braces a couple of tie wraps :wink:

Re: Axle drain plug

Posted: Thu Oct 25, 2018 8:13 pm
by myoldjalopy
Golly! Is their claim of "Reduce ≥30% engine abrasion, Prolong ≥30% engine use life' realistic? Quite spectacular and obviously well worth doing, if true....

Re: Axle drain plug

Posted: Thu Oct 25, 2018 9:27 pm
by philthehill
The longer you can keep the oil pure and impurities out of the oil circulation the better for the bearings and metal to metal contact surfaces.
A good solution is to use a high content detergent (diesel type) engine oil as the crud will be washed out of the oil galleries/sump and be carried to the filter where it is retained providing the filter or filter head does not have a by-pass valve which allows dirty oil to re-circulate.

Re: Axle drain plug

Posted: Thu Oct 25, 2018 9:30 pm
by MikeNash
I always glue the magnets in using something like Araldite. Even though modern ceramics are so strong that they should stick and not move, I hate the thought of one to moving upward into the rotating parts; it's peace of mind.
Like Phil, I believe you can't have too many so I've got them in all three drain plugs AND wrapped round the engine oil filter. Remember, full-flow oil filters only filter down to about 20-30 microns at best (bypass can be a lot better) but magnets can grab ferrous bits down to molecular size. Of course, such small bits must be close to the magnet to be grabbed - but they still do it. And in the gearbox and back axle we've no filter at all, and for here the magnet is in my view a God-send.
Below are the three drain plug magnets from my 1098, from the left b'axle, g'box and engine. Note that the captured bits on the central g'box plug are less "muddy" and more like little strips; too many crashed gears I suppose. These are all "Eclipse" ferrite rods of 1/4 inch diameter and 1/2 inch in length fitted about 10 years ago. I'm going to make new plugs with ceramic magnets which are much stronger.
Regards from MikeN.

Re: Axle drain plug

Posted: Fri Oct 26, 2018 11:02 am
by dudload
What about around the sump. Was thinking of getting these very strong pull magnets for oil filter and could just get more to put around the bottom of the sump. Any thoughts?

https://www.first4magnets.com/rectangul ... pull-p3690

Re: Axle drain plug

Posted: Fri Oct 26, 2018 11:34 am
by oliver90owner
dudload wrote: Fri Oct 26, 2018 11:02 am What about around the sump. Was thinking of getting these very strong pull magnets for oil filter and could just get more to put around the bottom of the sump. Any thoughts?

https://www.first4magnets.com/rectangul ... pull-p3690
Wrong choice of magnet. Look up effect of temperature on neodymium magnetsand you will see why.

Re: Axle drain plug

Posted: Fri Oct 26, 2018 12:31 pm
by dudload
Thanks for the tip. I guess these would work better? Need to get out and measure the length of the oil canister to get the best length.

Any thoughts on sump (apart from having to drop it to clean swarf off after a while)

https://www.first4magnets.com/rectangul ... pull-p3531

Re: Axle drain plug

Posted: Fri Oct 26, 2018 8:40 pm
by MikeNash
Re magnet types and temperatures, for the engine where the oil temp can get above 80C occasionally (measured on my 1098 on a hot day and a long drive of 2/3 hrs at 60mph motorway cruise) a samarium cobalt would be best: the "first4magnets" site above prices 5mm diaX10mm long magnets at only £1.29 each (or £5.15 for four) which is cheap enough. But for the b'axle & g'box the temp max is hardly ever as much as 50C, (at least on my Trav even towing on a hot day) so neodymium will do. But the price is hardly a concern.
Re magnets in the sump the effort in taking it off to clean the magnets is for me, too much, and I'll recommend and go for a magnetic drain plug and magnets around the filter.
Regards from MikeN.