Failed again! Rear brake issue...

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simonjrwinter
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Failed again! Rear brake issue...

Post by simonjrwinter » Mon Mar 25, 2019 2:08 pm

Not a happy chappy today.
Re-test this morning. Passed on everything apart from the brakes. I fitted (at the suggestion of the IVA tester) a restrictor in the rear brake line but when I mentioned it to the tester that I had fitted it he told me I couldn’t have an adjustable element to it . It was wound right in, so wasn’t influencing the brakes in any way. He tested the car and it passed all the braking tests apart from the rear offside wheel locked very slightly before the fronts.
I think I need to fit a fixed restrictor in the rear brake line to reduce the pressure, but am having difficulty finding something suitable.
Any suggestions?
Simon
TR6 (V8) Hawk 289 FIA (V8) Hawk 289 (V8) Doing my bit for global warming.

peterc
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Re: Failed again! Rear brake issue...

Post by peterc » Mon Mar 25, 2019 2:19 pm

Simon, do you not have Gerry’s pedal assembly with the Tilton brake balance bar so you could adjust the bias away from the rear.
Peter C

simonjrwinter
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Re: Failed again! Rear brake issue...

Post by simonjrwinter » Mon Mar 25, 2019 3:03 pm

Yes Peter, it’s the standard setup with the balance bar biased all the way to the front so minimal pressure on the rears.....
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simonjrwinter
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Re: Failed again! Rear brake issue...

Post by simonjrwinter » Mon Mar 25, 2019 3:55 pm

If I were to want to reduce the pressure on the rear brakes (not pedal pressure) would I need a smaller or larger master cylinder.
Simon
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simonjrwinter
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Re: Failed again! Rear brake issue...

Post by simonjrwinter » Mon Mar 25, 2019 5:04 pm

Both my master cylinders are .625 dia girlings.
Presuming I need a larger one for the rears for less pressure, should I go for .7 or .75?
Simon
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KevinW
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Re: Failed again! Rear brake issue...

Post by KevinW » Mon Mar 25, 2019 11:17 pm

Sorry to hear this Simon.
Have you tried just driving it to allow brakes to bed in a bit?

simonjrwinter
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Re: Failed again! Rear brake issue...

Post by simonjrwinter » Tue Mar 26, 2019 6:42 am

I’ve decided to fit the .7 master cylinder to the rear brake line. I’m also going to take the calipers off just to check they are working correctly and that the pistons are free to move in their bores ok. Is is a huge faff to take the calipers off a jag axle in a hawk?
Simon
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simonjrwinter
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Re: Failed again! Rear brake issue...

Post by simonjrwinter » Fri Apr 12, 2019 10:06 am

ITS PASSED!!!!!!!
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clive
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Re: Failed again! Rear brake issue...

Post by clive » Fri Apr 12, 2019 12:18 pm

Well done! Did you change anything?
Cheers, Clive.

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simonjrwinter
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Re: Failed again! Rear brake issue...

Post by simonjrwinter » Fri Apr 12, 2019 2:20 pm

Yes, upped the rear brake master cylinder to .7 from .625
Also renewed the rear pads.......I think the pads might have been the issue as they were so soft I could mark them with my fingernail!
TR6 (V8) Hawk 289 FIA (V8) Hawk 289 (V8) Doing my bit for global warming.

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