Leaking gearbox drain plug

[mr nurburgring]

Been under the car to find a small gear oil leak, bone dry apart from the drain plug, if I clean it with brake cleaner I can see it creep down the threads.

I guess it’s a taper thread that seals it?

I don’t want to use ptfe tape as this could split the casing I’m wondering if anyone has used pipe seal liquid?
Any solutions?
Cheers

 

[colb]

Its a tapered plug, a couple of wraps of ptfe plumbers tape will be ok to seal it, should not cause the hole to split, do not overtigten it just snug it up.

 

[mr nurburgring]

Its a tapered plug, a couple of wraps of ptfe plumbers tape will be ok to seal it, should not cause the hole to split, do not overtigten it just snug it up.

Thanks, I do have some ptfe tape, I’ll give it a go,

 

[Jfgoldfish]

Are the plugs on the 2.0 and 3.0 different?
My 2.0 doesn't have a tapered plug. Just an oring that could be sized up and replaced. A smear of RTV would work in a pinch.

Like this:

 

[mr nurburgring]

Are the plugs on the 2.0 and 3.0 different?
My 2.0 doesn't have a tapered plug. Just an oring that could be sized up and replaced. A smear of RTV would work in a pinch.

Like this:
821288_x300.jpg

No, the one on my gearbox doesn’t have a sealing o ring, just a taper thread.

 

[Jfgoldfish]

Strange. Maybe someone has dealt with this issue on my zed before.

 

[mr nurburgring]

Strange. Maybe someone has dealt with this issue on my zed before.

I believe you have a 6 speed, which is different, mine is a 5 speed 2.5.

 

[Jfgoldfish]

this issue on my zed before.
I believe you have a 6 speed

That's right.
That must be it.

 

[mr nurburgring]

Sorted the leak this evening.
Drained oil and cleaned threads with brake cleaner and applied loctite 577 thread/pipe liquid sealer

Left it to cure for 1.5 hours then refilled box and tested

Seems to have cured the problem, no signs of any oil creeping down the thread.

I drained the oil into a clean container and was surprised how clean the oil was and there was no trace of any fragments in there either.

 

[GuidoK]

None of the gearboxes have tapered plugs afaik
Afaik they're always M18 or old ones maybe M24 (so not tapered)
Plugs that either have a rubber seal or a copper or aluminium sealing washer are never tapered.

This is I think the old style plug for the S5D gearbox:


And the other one previously posted here is for the GS6 gearbox

 

[mr nurburgring]

The 6 speed are not tapered as they have a sealing washer, the 5 speed getrag box has tapered filler and drain plugs.

 

[GuidoK]

The plug I posted is the plug that's in the parts manual for the 5 speed, listed as m24x1,5 (metric)
http://bmwfans.info/parts-catalog/E85/Europe/Z4_2.5i-M54/R-N/2004/browse/manual_transmission/s5d_g_housing_mounting_parts/
What plug was in your gearbox?

 

[mr nurburgring]

The same as the one in the pic, 17mm

 

[GuidoK]

Yes 17mm socket.
But M24x1,5 isn't a tapered thread.

Or they use / made their own proprietary screwthread and called it m24x1,5 because that was the closest thing?

 

[mr nurburgring]

If it wasn’t tapered it would just screw all the way in and drop into the gearbox.

 

[GuidoK]

There's no internal shoulder?
hmm maybe not. Indeed then it has to be tapered otherwise it would indeed completely screw in :lol:

 

[mr nurburgring]

No, the taper is the seal.