My rear brakes don't work! I bled them, no air, brake fluid is flowing. It appears only one side of the calipers (outside) is working as the outter side of the rotors are clean. I think the inner pistons are siezed, the inner surface is rusted. I have heard of pistons siezing on, but never off. Anyone ever encountered this? could the calipers at fault or is it most likely the master cylinder just not sending enough pressure to move both pistons? Everything is quite rusted, I think the car sat for a long time.

'86 190D

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1982 300sd, new project car to restore

It doesn't matter if you know what you're doing, as long as you look like you know what you're doing.

I vote for calipers.

I had the same thing happen to my TD's rear calipers. I bought new ones.

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08 R320 CDI current

Past
95 E420
87 300D Turbo 5spd
90 300TE
83 300SD
85 300TD
92 400E
85 190D

The rear calipers have a smaller diameter than the fronts - they don't get used as much - if something will seize it will seize in the position where it spends most of its time (or there abouts)

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Thanks for the quick responces! I guess I will start hunting down calipers.

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1982 300sd, new project car to restore

It doesn't matter if you know what you're doing, as long as you look like you know what you're doing.

What is "ATE" design?

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1982 300sd, new project car to restore

It doesn't matter if you know what you're doing, as long as you look like you know what you're doing.

Have a look at the buy parts link above - find the calipers for your car - and you'll see that there are 2 types of calipers listed: Bendix and ATE. These are different manufacturers and different designs. EDIT:- I'm assuming this is the same for a W124 - as it is for a W123

You shouldn't mix brands on the same axle => for example (all) ATE front and (all) Bendix back = OK BUT ATE on front left and Bendix on front right = BAD!

I think this is recommended because the Bendix and ATE calipers have different sized pistons - i.e. the design is different

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

BENDIX or ATE caliper?
BENDIX or ATE caliper?

As stated, the pistons and hardware are not interchangeable.

You can use one brand or the other, but NEVER both brands on the same axle.




.

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1983 300D
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It might be worth your while just taking them apart and seeing what the damage is... corrosion will always be the killer - generally speaking if the piston's shiny surfaces are pitted and rusted I would call it a day and buy some new calipers - but post some photos first if you want to be sure / surer.

The downside to doing this is the down time involved - it can be an easy job - but I wouldn't count on it. Murphy's law can really bite you in the soft bits if you need to get it done quickly for this sort of job!

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

calipers are usually very easy to rebuild. the only possible snag is when the pistons are well seized and you can't remove them.

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punkinfair

x2, I always try and rebuild before I replace. Rebuilding calipers is quick and easy. The only gotcha is if the piston or the bore is rough or pitted - then it's time to buy a new one.

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'98 E300 turbodiesel

Weird,
Make sure you check the thickness of your disks. When they get thin, if you have pads that are on the way out, the pads have trouble contacting the disks as they are held apart by the anti rattle components.
Some times a little brake clean or wd40 sprayed under the dust seal will loosen them enough.

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

Just for what it is worth, my 240d had both rear pads rusted stuck in the caliper. The piston in the caliper moved just fine.

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1977 240D turbo

NAPA has rebuilds.

Can't afford down time. My only ride. If I take them apart and they are fubar I am screwed! I located TRW ATE style with pads for $24 each! How can I go wrong with that! New calipers pads and rotors, I think that should fix any problems. I will probably do the front brakes after X-mas as they are getting low.

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1982 300sd, new project car to restore

It doesn't matter if you know what you're doing, as long as you look like you know what you're doing.

You are on the right track weird ! If they dont have a core charge (change over), you will be able to clean up the old ones, get them working & sell them on fleabay !!

__________________
Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving