Rounding off brake line bolts! Help needed!
Turbo Mini Forums

Hi all,

I need to replace the master brake cylinder and clutch master cylinder on a Metro Turbo.

I tried to undo the brake lines from the master brake cylinder but they're seized and I'm close to rounding off the bolt.

I tried vice grips but it made it worse as the metal is quite soft.

Anyone have any ideas? I have heard of others having better success with flared wrenches?

I want to get the right technique so I can replace the clutch master cylinder too.

Please see pics...





Any feedback would be much appreciated!

Edited by metroturb on 21st Jun, 2014.

Get a proper brake pipe spanner, but be prepared to cut the pipe to undo the union nut with a 6point socket, obviously then you will need to make new brake pipes.

As tom says, sometimes cut the pipe and a 6 point socket, I've had good results removing rounded off unions with a pipe wrench

I have one of these. it is relatively wide (wider than the nut) and super stiff (it will NOT open up like some cheaper versions and kill the nut) and tight fitting hexhead.

Stahlwille 41081012.

best 20 quid I spend on spanners

I suggest liberal and multiple applications of a MOS2 type penetrating oil over a few hours or better a few days. applying a but of focussed heat can help it penetrating but do try not to burn the car down

if that does not work (so far i have not had that happen when you start with the right tool) I second the pipe wrench (or vice grips and brute force but you will trash it in the process)

Edited by Sir Yun on 21st Jun, 2014.

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

As it's already fucked, I'd cut the pipe and use a Irwin bolt extractor socket thingy.

A replacement pipe is pennies.

In the 13's at last!.. Just

No reason you cant get that with mole grips. You need a decent pair tho and dont be shy on locking them on. You will still need to replace the nut but if you can get it out first you only need to cut off the flare and can maybe reuse the pipe. I you cut it off as is you will loose 20mm of pipe and that may make it to short to use again.. Just my take on it..

Oh and as always used a bit of heat.

vise grips or pipe grips with work if all else fails (good quality ones though)

I had the same problem used mole grips in the end totally rounded of so got a new pipe

Just get hold of a correct spanner. It will hold the nut correctly and generally avoid this.

Yip, good quality tools make a huge difference here..

Snap On flank drives are very strong for open end spanners.
IMO stronger than a "cheap" open tipped brake pipe spanner.

Or these work very well for such things, and wont risk damage the same way normal vise grips can do

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Undo the other end and slide a normal ring spanner up the pipe.

Metric is for people who can't do fractions.