Every day is a school day...brake hose/line replacement fun
 

Hi all,
In the last 48hrs I've gone from sitting and scratching my head, to being a brake line swaging ninja and actually being able to remake brake lines and unions at will!

My beloved 940 estate failed it's MOT on Saturday on some pretty minor stuff...a worn rear tyre, play in a track rod end and a perished brake hose.

"SIMPLE!" Cried I...a tyre is child's play, a track rod end is amongst the easiest jobs out there, and a brake hose must be...erm...simple enough, surely?

It wasn't.

With my freshly acquired set of flare nut spanners, the caliper end came undone like a dream. The other end, however, was a total nightmare. The union rounded off instantly, and no amount of persuasion with mole grips or similar would budge it, ending up a totally mashed-up mess. I'm a bit of a perfectionist and the whole thing was so horrible I could barely look at it!

In despair, I did what most conscientious fortysomething amateur mechanics do...I rang my Dad. My old man, now well into his 80s, has more mechanical experience than anyone I've ever met, he was a development engineer for Standard Triumph, and was the first person to introduce exhaust tuning to motorsport. He then jumped ship to Tecalemit Jackson and was one of the pioneers of fuel injection in collaboration with Bosch. Following this, he ran a series of successful garages of his own over many years.

I often ring him with mechanical queries, and his response is always the same. A sigh, an "oh dear", a deep breath and "listen carefully, I'm going to tell you exactly how to sort this out, but I won't repeat myself, so make sure you're listening properly!" He is always right, and his solutions always work perfectly.

This time, he told me I needed to cut the mashed union up and remake the brake line, using a swaging tool, a handheld pipe bender, a small C-style pipe cutter and a spool of 3/16" copper line. I'm a confident DIY spanner spinner with these cars, but for some reason this job seemed beyond my pay grade.

I bought the tools and pipe (all marked boldly "ONLY FOR USE BY A QUALIFIED MECHANIC" by Halfrauds, which was a confidence booster 🤣) and went to work. I cut the line back cleanly, deburred the end, slipped a fresh union on, executed a perfect SAE standard double-flare at the first time of asking (which was something of a surprise!), Bolted the union to the new hose, clipped it all back into place, bled the system with my very useful Gunson Eezibleed, bolted the whole thing back together and...

To my delight, it worked like a charm! The car stops perfectly, no brake imbalance, no pull, zero leaks and 100% success.

I've never done any brake surgery before, beyond bleeding, pads, discs and slide pins. I've always considered this stuff too high-stakes for an amateur ratchet wrangler such as myself, but this job has boosted my confidence immensely.

The bus is back in for its retest tomorrow afternoon...fingers crossed the tester agrees with my assessment of it being a decent enough job!
To my surprise, it works perfectly.

Glad you got it sorted, yes brake pipes are one of those things where you just have to dive in and do it then realise there was nothing to be worried about in the first place.

Brake union
 

First - well done. I have a similar situation, managed to get one of the unions free and replaced the rubber hose, but have fubared the other side (apparently mole grips will do this). Did you happen to take any snaps while everything was apart e.g. site of cut/join?

jor

Excellent stuff Phil! Your dad gave you some very good advice there as well. You won't be worried next time you have to do it either! :thumbs_up:

Unfortunately I didn't take any snaps...I did think of taking some pics but was up to my elbows in brake fluid so benched the idea as I wasn't sure if it would eat my phone! I'll take some pics of the finished area this eve when the old girl comes back from her MOT.

You did well to turn to someone with your dad’s experience to advise you on this. Most of the YouTube videos on flaring brake line are wrong, some dangerously so.

Well, it worked! MOT passed with just advisories on both front tyres approaching the legal limit (booked in for the end of next week) and my drop-link bushes being a bit scabby...another thing which has been on my to-do list for a bit and will get done in the coming weeks.

Hurrah!

Whilst YouTube is handy for reference sometimes (usually when squared off with a large helping of common sense!), I personally wouldn't rely on it for advice on something as important as brakes. If bad advice prevents you getting going, it's one thing, but if it prevents you from stopping, it's quite another!!

brake hose
 

hi
i fitted new front callipers to my 940 that part the job went well with the intention of replacing brake hoses my self but no way could i release the hoses at the copper pipe end so my mechanic did the job but 1 piece of brake line had to be replaced about 14 inches so after 21 years of ownership we finally have new callipers and hoses . also i have just replaced the drivers side ABS sensor not to bad a job read my thread