exactly what it says on the tin...
306 d-turbo (97-P) suffering from severe brake fade... can anyone help?
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Just started out of the blue, fitted anything of late, useage wickedly hard?
M.M
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Are they hot if you get out and feel them, or is it a hydraulic pressure loss? Is the pedal overly hard or spongy? does it sink while braking?
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Please define "Severe"
Are you comparing this car to another (with stronger brakes?)
What condition are the brakes in?
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groups.msn.com/honestjohn - Pictures say a thousand words.....
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My 306 used to do this and I think most of them do it with 'spirited' driving. Most 306's use the same size discs as the 106 and 205. I didn't take any chances with mine though. It could have been the cheap pads and discs that the previous owner had fitted, but I replaced the calipers and discs with the setup found on the Citroen Berlingo and Peugeot Partner vans. 266mm discs and decent pads. Its a straight swap and I highly recommend it!!
Sorry, I don't really have an answer to your query though, it could be inferior pad material or worn discs or simply just your driving style!
Ross
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I suspect, if the brake flluid has never been changed, that your brake fluid has absorbed enough water to boil on sustained braking. Steam is compressible so very little pressure is exerted on the brake pads hence no braking.
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if the pedal sinks, whilst braking, it is likely to be the master cylinder seals on their way out. I would get it seen to very quick.
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they are ok ish until braking pressure is sustained... then the pedal goes soft. The brakes on this were never amazing so I changed the pads, hoses have been changed after a leak and I know the rest to be in fairly good order since I do my own maitenance... (Yes I do know what I'm doing)
May or may not be linked but the rear cylinders/pistons (in the drums) have also been changed as they were leaking fuid inside the drums. All been cleaned up poperly etc.
Handbrake has been adjusted last week to no effect.
Cheers...
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jm,
If pedal travel is longish all the time but feels worse when braking hard it might be the rear shoes. They could be worn below an acceptable thickness, if they were contaminated with brake fluid they should have been changed, also the auto adjusters might not be working.
I assume you've completely changed the brake fluid to be sure that is OK?
If the fade happens after ten miles of very hard driving it could just be cheap pads.
If the fade happens when you brake hard, even when the brakes are quite cool, then the master cylinder might need replacing.
M.M
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Jim,
I am sure that this won't be much help but I had a 306 xtdt a few years back (M reg). I thought that the brakes were a bit soft so asked the dealer to sort out and all manner of problems came after.
Each morning there was zero back pressure on the middle pedal but after the first application it came back to normal. When I parked up for 20-30 mins this would happen again.
Dealer had it for 4 months off and on to try and sort the problem but never did. Eventually I sold the car as I was too "afraid" of driving it. This was after I was going about 100mph with a friend on an autoroute and came off the slip road and got the fright of my life when the brakes didn't respond properly!
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I'm not sure your brakes are fading as this would normally only occur when the brakes become extremely hot after very heavy and prolonged use ..If you adjusted the handbrake cable to get the travel correct this may be the source of your problem as the shoes will need a couple of pumps on the pedal to get them to bite on the drum - could cause a soft pedal..handbrakes never usually need adjusting as the cables rarely stretch .I always have to adjust 306 rear drum brakes using a screwdriver as the auto adjusters never seem to work properly. Sorry if you knew all this allready but i have heard of alot of alot of people doing this.
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Sounds like a vacuum leak or a vacuum pump fault. Diesels use a vacuum pump rather that the inlet manifold over-run vacuum associated to petrol engines. Check the non return valve and and piping , then get the pump checked by pug. This is why is started suddenly. Regards Peter
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I?ve been out to the workshop for you and it is clear that pug tend to use a cam shaft driven vacuum pump and as a guide at idle the pump should pull 500mmHg. Check all the pipes and feel them for consistency. Some failures are due to the inner layer collapsing and shutting off the vacuum. Good Luck Regards Peter
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Peter,
You are right to bring the servo pump into the arena as it is another of those things folks don't think of untill they've done everything else.
However, trusting Jim's report of "fade" and a "soft pedal" I thought the vacuum/servo should be sound as that failing gives poor braking with a hard pedal.
M.M
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Yes M.M, I know what you mean but if the vacuum is low or a collapsed pipe you do get the initial braking which gives you the travel but then as the vacuum falls the pedal falls some more without any increased braking. If the rear shoes were contaminated it just would not brake well from the outset rather then a feeling of fade. A leak in the Vacuum Servo Diaphragm is also worth testing for. Don’t forget to test it in its relaxed state and when pressed. Regards Peter
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