Saturday, April 16, 2011

Broken brakes diagnosed

I think I've got to the core of these dodgy brakes - in my previous blog entry I described how they would come on and stay on almost at random.

Well it wasn't a pipe too close to the exhaust, it wasn't the servo, it wasn't the pedal return spring or the pivot pin seized, it was the master cylinder - or at least I think it is.

I went through the "non-invasive" ideas that I gathered from the Club Triumph Forum and from responses to this blog - thanks readers :-)

I was away this week so I ordered parts for a master cylinder rebuild, unfortunately the wrong ones turned up and I didn't know enough to see they were wrong until I had stripped it down. Apparently there are 2 single circuit versions, 13/16th bore and 3/4 bore. Anyway, I have ordered the right parts (and cancelled today's MOT) I'll have to sort it out in the week, I think I am on the road for work only once and that's a day trip into the city so it should all be OK to meet the new MOT deadline of Thursday.

Annoying as I had plans for the car this weekend but it can't be helped.

The master cylinder was deceptive, it looked fine, fluid was clear and it seemed to function OK. However, when I came to drain it fully all manner of filth and nastiness came out - I really thought it would be ruined inside but the bore is clean as a whistle and the piston fine. It looks like one of the the seals has gone back to nature, the cup seal is really more akin to fruit pastel than a seal. I've cleaned it all out ready for new rubbers.

I've also bought and fitted some stainless anti-vibration straps for the rear subframe mounts. I noticed one was broken and when I changed the other it was very thin and showing signs of fracture too. I didn't especially want stainless but it's not a bad idea as they do sit in the firing line of all the road crap there.

The last few jobs were to clean and lubricate the brake pedal pivot and now I've come in to order the correct colour wire for my newly relayed pump - it's got some cobbled together "see if this works" temporary wiring in there at the moment. As I need a long length I may as well get the right colour and spec. I think I will also treat myself to a new crimper, might get a nice professional one as the one I have is pretty old and crap - the professional one I have for Lucas bullets is really good.

So, to finish off, I am feeling very much happier with the car although I still haven't actually fixed it yet and I still haven't been able to get out and drive it yet -I have patience :-)

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