32 replies to this topic

[taffy1967]

I had mine heli-coiled last year and it cost around 60 quid.

I was able to take my Mini to the engineering firm/garage and they did a splendid job.

They machined an almost identical sump plug complete with the magnet to suit and okay they dropped the tang into the gearbox, but the sump plug magnet picked it up.

Yes when I came to do an oil change, the tang was attached to the magnet and I nearly had a fit thinking my gearbox was on the way out.

Anyway, so long as you have a magnet fitted you should be okay and they did the work with the engine and gearbox fitted.

Edited by taffy1967, 09 September 2008 - 10:22 PM.

[markaboot]

i could be wrong, because i havent had a proper look. so it might not be possible or it might be very bad practice.
but could you not drill it out and tap it a larger size, then jus stick i bigger nut it?

[HARBER07]

i could be wrong, because i havent had a proper look. so it might not be possible or it might be very bad practice.
but could you not drill it out and tap it a larger size, then jus stick i bigger nut it?

Its what i have done sort of. But i know ill get a slap off someone for doing it.

[taffy1967]

Well a few years back a so called gearbox specialist fixed my gearbox (long story), fitted a new clutch and supposedly fitted a heli-coil to the sump plug hole. They then seriously ripped me off because for starters they hadn't bothered fitting a heli-coil, no they just whacked in a larger bolt instead that had no magnet.

Trouble was a few years later the thread failed again and I was left with a spinning bolt.

That's when I took it elsewhere and got it fixed properly with a heli-coil and a new sump plug with a magnet.

So you could use a larger bolt, but chances are the threads will fail eventually.

[HARBER07]

I used one of these: Click

With a couple of dowty seals, and a 3/8" plug in the end, im not constantly wearing the threads down in the gearbox casing.

[taffy1967]

Well if it works for you then good, but it does help if there's a magnet doing it's job there too.

[HARBER07]

Oh yeah i forgot to say that i have one of them magnet things that bolts to the back of the block where the oil pick up pipe joins to the oilways. Anyways its up to you really, but this system works for me.

Edited by HARBER07, 10 September 2008 - 09:47 AM.

[dklawson]

If you choose to use the magnet that mounts on the back of the gearbox... do not forget to check and clean it frequently.

Unlike the sump plug magnet, the optional one for the back of the gearbox is often ignored during oil changes. (This is a second hand report as I have no intention of using those magnets myself). A friend in OZ used those magnets and said once the debris on the magnet got to a certain size, a huge ball of debris got sucked off the magnet and blasted into the oil pump. He said the results were not pretty. So, if you use the magnet Harber07 mentioned, check and clean it often.

[HARBER07]

Thanks for the info DK. That wont be a problem for me as such as im always in the engine bay at weekends

[BiMU]

Thanks for the reply guys. I went to a place that sold helicoil kits and the guy said that the kit would cost about £60. Now even if I did purchase the kit, I had a look at the sump again to see what kind of clearance I have to play with and the answer is... not a lot at all. I'm not even sure how you would even go about getting the drill bit and drill in there let alone the tap! I also called place up and they were asking for £110 for them to tap and helicoil it.

Do I have any other options other than helicoil and tapered plug? Its starting to look expensive!

[taffy1967]

Ring around for quotes, try a good engineering firm or a garage that specialises in gearbox repair work.

Also ask around at your local Mini Club, because they may be able to help or point you in the right direction.

[Dan]

could you not drill it out and tap it a larger size, then jus stick i bigger nut it?

Seems a lot of work to then end up with the wrong size plug, probably without a magnet. Since the drilling and tapping is the hard part, once that's done you just wind the Heli-coil in and fit the plug.

Pretty much no other options beside what's listed here Jason, a tapered plug, a Heli-coil or re-tap for a different bolt or fitting. As said above tapered plugs are OK and people have used them for years but there's always the chance that the next time you tighten it the transmission case will crack.

[norwegianminiman]

we (me and my dad) are planning on fitting a tapre plug as a temporary fix, intend on taking the gearbox out in the spring anyway, just need the oil to stay in the gearbox until we do...

[BiMU]

Hi guys,

Just wanted to let everyone who gave me advice that in the end I just took the mini to a local mechanic and heli-coiled it for £55. Will never cross-thread again... i hope! Or over tighten!

Jason

[dklawson]

I eventually post this on ALL the sump/HeliCoil threads. It's time again.

For those of you who still have a stock (non-HeliCoiled) sump and are using the copper sealing washer, there is an alternative. You can use a 14mm bonded metal/rubber drain seal OR a 14mm nylon washer instead of the copper. The copper is good mind you... but you have to apply a fair amount of torque to get it to seat. Over time you run the risk of damaged threads even if you're careful. With the bonded metal/rubber seals all you need to do is tighten until the rubber is compressed and you have a nice tight seal without excessive torque. 14mm drain seals should NOT fit the Mini drain plug but with a bit of twisting they will fit.

For reference, the bonded seals look like this:
http://www.creativer...ded_seals_8.jpg