Brakes: master cylinder or brake servo going?

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macplaxton
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Re: Brakes: master cylinder or brake servo going?

Post by macplaxton » 26 Aug 2010 06:04 pm

Is it really well serviced?

I worry when *if* the job has been done, whether by an independent or main stealer unless I've seen it been done with my own eyes.

Has the fluid been changed every 24 months?
Has the perishable items (hoses, brake seals) every 48 months?

I suspect not, but I'm sure they are on the service sheets.
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trabitom99
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Re: Brakes: master cylinder or brake servo going?

Post by trabitom99 » 26 Aug 2010 06:28 pm

Brake fluid yes, perishable items I guess not ... But I do have a bit of faith in the Volvo dealer in Cologne who serviced the car while it was with it's previous owner. The mechanics were all a little bit older, the place was a bit smaller and grubbier than the gleaming places in Bonn which also sell Land Rovers where you just know there's no one about who's ever changed a variomatic drive belt.

The garage near me I usually go to is OK, but they're overworked, get lots of cars in and out, and usually go for the "quick and easy" option.

Tom
343 GL Touring B14.1E CVT (155) 98000kms 1980 (sold)
343 L Junior B14.3E MT4 (155) 229000kms 1981 (scrapped)
343 DLS B19A MT4 (155) 167900kms 1982
360 GL Injection B200F MT5 (231) 348598kms 1988 (scrapped)
360 GLT B200F MT5 (302) 230000kms 1988

Ride_on
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Re: Brakes: master cylinder or brake servo going?

Post by Ride_on » 27 Aug 2010 04:03 am

A spongy brake pedal is a pretty simple and standard problem. The garage has not diagnosed the problem they are just randomly changing parts, they should have inspected all the parts first, it seems likely they didn't or they havn't done the bleeding correctly. Getting the drums off can be a pain so they may have avoided this. If you are not doing this yourself then I'm not sure how help much we can be.

If the pedal is spongy you are not getting pressure building up in the system. This can be because:
1. The pads/shoes are moving too far to hit the metal surfaces, and not adjusting in close.
2. The fluid is leaking out continuously
3. There is air in the system
4. The master cylinder is leaking
5. Something wrong with the pedal itself.
6. Flexihose partial rupture blowing out

If the problem wasn't fixed I don't understand how they can give the car back to you, especially in an unsafe condition.
1980 345 DL_______1987 360 GLE (project car restored to GLT spec and B230FT'd)
1984 360 GLT______1987 360 GLT
1983 360 GLS______1989 360 GLE
1985 340 GL_______1986 340 1.4
1985 360 GLS______1995 940 SE 2.3 Turbo Estate (daily)
1987 340 GL 1.7

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Speedy88
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Re: Brakes: master cylinder or brake servo going?

Post by Speedy88 » 27 Aug 2010 01:33 pm

For future tinkering, how do you get the rear drums off? My current technique is to take the wheels off, start the car on axle stands and in gear and "shake" the drums off. Doesn't seem right though.
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trabitom99
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Re: Brakes: master cylinder or brake servo going?

Post by trabitom99 » 27 Aug 2010 03:58 pm

Ride_on wrote:If you are not doing this yourself then I'm not sure how help much we can be.
You're definitely a help, by getting me to understand the problem I'm better equipped if I get fed a load of balls at the garage and buy the wrong parts afterwards :-)
Ride_on wrote:If the problem wasn't fixed I don't understand how they can give the car back to you, especially in an unsafe condition.
They've known me for a while, and the distance between them and me isn't very far at all. I've had places refuse to give cars back to me in the past though, with lesser problems.
Speedy88 wrote:For future tinkering, how do you get the rear drums off? My current technique is to take the wheels off, start the car on axle stands and in gear and "shake" the drums off. Doesn't seem right though.
There are brake drum "pullers" as far as I know which look something like this:

Image

Cheers

Tom
343 GL Touring B14.1E CVT (155) 98000kms 1980 (sold)
343 L Junior B14.3E MT4 (155) 229000kms 1981 (scrapped)
343 DLS B19A MT4 (155) 167900kms 1982
360 GL Injection B200F MT5 (231) 348598kms 1988 (scrapped)
360 GLT B200F MT5 (302) 230000kms 1988

Ride_on
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Re: Brakes: master cylinder or brake servo going?

Post by Ride_on » 27 Aug 2010 11:30 pm

Not sure I'd recommend a brake drum puller, you will probably wreck stuff pulling it off, but sometimes its worth sacrificing parts. My brakes were fairly seized on my project 360, wheels just about turned. My method;

Screwdrivers, pry bars and a claw hammer.

You can always move the drum a little ways away from the hub as the shoes are held on with springy things, so lever the edge out and apply some force then hit the thick rim but with the hammer, with each hit you should get a little movement. Work around the edge using the larger tools (bigger pry bars etc), the bottom of the drum is good to works against as the pads are more rigidly held here. So start at the top and work your way down with a lever gradually pushing in more on each side.

Sometime to start I use the claw hammer to lever out the drum then wedge a screwdriver and use the hammer to hit the drum.
1980 345 DL_______1987 360 GLE (project car restored to GLT spec and B230FT'd)
1984 360 GLT______1987 360 GLT
1983 360 GLS______1989 360 GLE
1985 340 GL_______1986 340 1.4
1985 360 GLS______1995 940 SE 2.3 Turbo Estate (daily)
1987 340 GL 1.7

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trabitom99
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Re: Brakes: master cylinder or brake servo going?

Post by trabitom99 » 02 Sep 2010 02:52 pm

Update time:
Ride_on wrote:If the pedal is spongy you are not getting pressure building up in the system. This can be because:
1. The pads/shoes are moving too far to hit the metal surfaces, and not adjusting in close.
2. The fluid is leaking out continuously
3. There is air in the system
4. The master cylinder is leaking
5. Something wrong with the pedal itself.
6. Flexihose partial rupture blowing out
The answer was: no 6. The rear RH brake hose had had it ... A pity they changed the master cylinder first before checking the hoses :?

Thanks again for all the good advice!

Tom
343 GL Touring B14.1E CVT (155) 98000kms 1980 (sold)
343 L Junior B14.3E MT4 (155) 229000kms 1981 (scrapped)
343 DLS B19A MT4 (155) 167900kms 1982
360 GL Injection B200F MT5 (231) 348598kms 1988 (scrapped)
360 GLT B200F MT5 (302) 230000kms 1988

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jtbo
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Re: Brakes: master cylinder or brake servo going?

Post by jtbo » 05 Sep 2010 02:45 pm

Those hoses are good to replace if not know when they have been replaced. I had rupture even my car was not used on road, had ruptured when I did move car on yard :shock:

Only reason why I haven't replaced rear hoses yet is because bleeding the brakes seem to be real PITA for me, but then again I have not used air pressure.
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