[Othen]

Let me just run this past you chaps:

I had the Skoda serviced + a MoT about 10 days ago. I've used the garage for some years and they have always done a good job in the past. The car passed the MoT with no problems, as a result of the service checks the garage recommended that the brake fluid be changed as it was heavily contaminated.

I was somewhat surprised as I knew I'd had the fluid changed only 18 months ago (October 2018); the garage said they could change it for £70, but I declined - it is an easy enough job so I thought I'd do it myself.

When I got home from the MoT and service I tested the fluid myself and found the stuff in the master cylinder had >4% water contamination - which amazed me, I'd never seen such contamination in either a bike or a car previously. I vacuumed the fluid out of just the master cylinder and re-filled it with fresh until I had time to change the fluid myself - which was today.

I tested the fluid in the master cylinder again before I started today and found it <1% contaminated. Having just vacuumed and re-filled the system I tested the stuff from the lines, and I'm perplexed to find that also was less then 1% contaminated.

Something strange is going on here: somehow only the fluid in the master cylinder was contaminated, that in the lines and slaves seemed to be good. Unless someone can think of another explanation I can only conclude either:

a. The garage (Halfords) that changed the fluid in Oct 2018 didn't actually do it, and just filled the master cylinder (perhaps accidentally) with some contaminated fluid.

... or:

b. The reputable local garage that carried out the major service and MoT a week or so again contaminated the master cylinder fluid to drum up a bit more business.

I can think of no other explanation than the two above: I've owned the car from new so I can vouch for everything that has been done to it, I keep it really well serviced, it has covered less than 70,000 miles (and only about 7,000 in the last 12 months) and it has no faults. The bleed nipples were all a bit difficult to undo, it is hard to say, but they didn't look as if they had been undone only 18 months or so ago (the time before that was in 2015 - by the Skoda dealer, the car still being in warranty at that time).

Can anyone offer another explanation? Otherwise I'll have to conclude that one of the two garages is up to something suspicious. I have no way of knowing now whether or which of the garages might be responsible, in that I didn't test the fluid myself in the period between having it changed and the recent service.

Unless I've missed something blindingly obvious the moral of this story is: if you want something doing properly, do it yourself.

:-(