Panda Matt
Part of things
Datsun Owners Club Wannabe
Posts: 734
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I recently noticed that the performance of the brakes on my fasty were not what they once were, and that it had an unnerving tendency to pull towards the pavement under severe load. Then it started making a swishing noise occasionaly - careful testing revealed this not to be knackered bearings, but the brakes sticking on...
Not being overly happy about this, and wanting the car to be doing well for CaRS, I purchased some new pads and discs for the front.
When it came to put it all back together, I couldn't push the pistons back into the calipers - aha, that'll be the problem then. A quick phonecall to T3D should have meant I had a week to put some reconditioned calipers (new ones no longer available) before cars. City-Link's "quality" service standards meant I actually had to fit the calipers Friday night before driving up to CaRS after work on Saturday. This actually went quite well considering, and the new calipers were on, ready to be bled at around 8:00pm.
After 2 1/2 hours of trying to get tehm to bleed, including using a huge syringe, and the factory vacuum pump system, I concluded that the funny noise I'd heard when starting to pump the system was actually the seals inside the master cylinder going.
Went to CaRS in the Plan-B Seat Arosa, drove back via T3D in Cambridgeshire to pick up a new master cylinder (mostly to avoid City-Link).
Fitted the master cylinder this Friday, came to bleed the brakes - and it worked! Sort of.
After bleeding the brakes all of the way around the car (starting at the longest pipe run), it seemed ok - there was resistance in the pedal. Parked up and locked up the workshop. Started it up to set off home, and suddenly - no brakes. Bled them again, locked up again, no brakes again.
There are no obvious leaks on the system, and the reservoir doesn't seem to go down.
Anyone got any ideas?
The only other thing that is nagging at me is that when I went to get some brake fluid from Halt-fords, although the fasty wasn't listed in the helpful reference guide, bugs and type 2's were listed as Dot-4 fluid. When I checked my hasitly scribbled notes from T3D, I was recommended Dot-3 fluid - could this be the source of my woe?
Helpful replies appreciated
Matt
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is the new cylinder still pushing fluid?? it is possible that when bleeding you could have turned the seals (probably not but its the only thing i can think of)
the DOT rating isnt going to make any difference, this only has any issue if you put 5.1 in a dot 4 system
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crack the unions off and bleed the master cylinder first
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mercmad
Posted a lot
Flush Hard,it's a long way to McDonalds.
Posts: 1,740
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That would be my answer too,Always "bench Bleed" the master cylinder first because they are double acting and if any air is in the first stage it wont push the second piston in far enough. ...and don't drive with dodgy brakes,the excuse won't wash in court.
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Many years ago I changed my driving style to cope with rising fuel prices; I have now reached the stage where I am contemplating keeping my eyes shut in order to lower wind resistance.
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actually come to think of it...
when i fitted a new master cylinder, it had 4 ports, when i only needed 3. so i blocked one with a bleed nipple and used that to bleed the cylinder first.
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:)I've often found that the best way to bleed brakes is to fill the reservoir, undo all the bleed nipples and simply let the fluid run out...let gravity do the work. No chance of pulling air back in when the pedal is released cos the pedal won't have moved!
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Snoozin
Posted a lot
Toyophile
Posts: 1,557
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That's my method on the Alfa, it's always worked perfectly for me as long as you keep an eye on the reservoir.....
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If after bleeding the master you find that there is still a problem with the pedal fading, try clamping all 4 flexi's and then try it. If your pedal is hard then you know the problem isnt at the master cylinder but at one or more of the corners. Release 1 clamp at a time, trying the pedal each time. When you find that you release a clamp and the pedal goes soft agin then thats the corner where your problem is. What you are describing does sound like air in the system to me though. If you can get hold of a bleeder that sucks the fluid through, i find that these are the best. Another good method is to take off the resovoir cap, chock the pedal down and leave it over night. The constant pressure will force up any air back to the resovoir as it has some where to escape to. Good luck! :-)
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Panda Matt
Part of things
Datsun Owners Club Wannabe
Posts: 734
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Jul 11, 2006 19:51:43 GMT
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Thanks all for helpful responses. I think I've fitted the calipers to the wrong sides as well. Plan for the weekend is to swap the calipers, change the bits of flexi between reservoir and master cylinder as they are looking a bit knackered, then bleed master cylinder, then let the brakes bleed themselves out as suggested. That'll be my Sunday used up (Friday night = Jazz festival volunteering, Saturday = Volunteering, then Jazz festival customering) Dudes, identify yourselves at the next R-R meetup and I'll buy you a beer * *if the brakes are working by then
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street
Posted a lot
6.2 ft/lbs of talk
Posts: 4,662
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Jul 11, 2006 21:02:31 GMT
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Thanks all for helpful responses. I think I've fitted the calipers to the wrong sides as well. Plan for the weekend is to swap the calipers, change the bits of flexi between reservoir and master cylinder as they are looking a bit knackered, then bleed master cylinder, then let the brakes bleed themselves out as suggested. That'll be my Sunday used up (Friday night = Jazz festival volunteering, Saturday = Volunteering, then Jazz festival customering) Dudes, identify yourselves at the next R-R meetup and I'll buy you a beer * *if the brakes are working by then Hmm, that could be your problem then too- If you've put the calipers on the wrong sides the bleed nipples will be in a different place to how they are intended to be when bleeding. This is a problem I had with the rear disk conversion on my escort- The brackets held the caliper in a different position on the disk to how they are fitted on the Sierra they origionally came off. Taking the calipers off the brakets and sitting them on top of the disks while bleeding was the answer, then bolted them back up. Shame you didn't get to CaRS in it, hope you get it sorted bud.
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Panda Matt
Part of things
Datsun Owners Club Wannabe
Posts: 734
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Jul 11, 2006 21:30:34 GMT
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Hmm, that could be your problem then too- If you've put the calipers on the wrong sides the bleed nipples will be in a different place to how they are intended to be when bleeding. Shame you didn't get to CaRS in it, hope you get it sorted bud. Cheers, it's appreciated - but there's always next year... loved your bullet holes btw The replacement calipers were different to the originals - which had 2 bleed nipples on the old vs. just 1 on the new... The new ones need the bleeder at the top apparently
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Tarka
Part of things
Posts: 905
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Jul 11, 2006 21:30:37 GMT
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I know its a nancy boy way of doing it but my Eazibleed system using the spare wheel is great because the system never draws air back in. Mind you, Gerry Marshall wouldn't have used an Eazibleed, he'd have just sucked the fluid through with a straw.
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Sharks in the garage.🐬🇩🇪 I'll finish my projects when you've finished your's!😎😜
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Panda Matt
Part of things
Datsun Owners Club Wannabe
Posts: 734
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Jul 18, 2006 12:33:29 GMT
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Thanks to all for help - swapped calipers over, system bled fine afterwards...
Didn't make the T3D open day though...
Must take some photos now to share on readers rides
Thanks again
Matt
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Jul 18, 2006 14:54:41 GMT
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The replacement calipers were different to the originals - which had 2 bleed nipples on the old vs. just 1 on the new... The new ones need the bleeder at the top apparently I know hindsight is always 20/20.... but the bleed nipple always needs to be at the top! If there is an air bubble in the calliper its not going to sink to the bottom.
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1972 Fiat 130 1985 Talbot Alpine 1974 Lancia Beta Saloon 1975 + 1986 Mazda 929 Koop + Wagon 1982 Fiat Argenta 2.0 iniezione elettronica 1977 Toyota Carina TA14 BEST CAR EVER!!!!!!!! 1979 Datsun B310 Sunny 4-dr 1984 Audi 200 Quattro Turbo 1983 Honda Accord 1.6 DX GONE1989 Alfa 75 2.0 TS Mr T says: TREAT YO MOTHER RIGHT!
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Panda Matt
Part of things
Datsun Owners Club Wannabe
Posts: 734
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Jul 18, 2006 16:42:02 GMT
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The replacement calipers were different to the originals - which had 2 bleed nipples on the old vs. just 1 on the new... The new ones need the bleeder at the top apparently I know hindsight is always 20/20.... but the bleed nipple always needs to be at the top! If there is an air bubble in the calliper its not going to sink to the bottom. In my (shaky) defence , The new calipers were offered up and compared to the old ones. The inlet for the flexi-hose was used as the point of reference.. Old calipers: =/\o .| | [to Car] =\/ ('=' is bleed nipple, 'o' is flexi hose fitting) New calipers (fitted wrong): . /\o .| | [to Car] =\/ ...but yes, yes, I am a numpty for assuming the air would be pushed out with the fluid when bleeding, and that the flexi hose would be less likely to be damaged at the top - sincere apologies, and I wont do it again...
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