The rebuild kit for your car, both front brakes, is available from Fastlane for under $60. The job is not that complicated, the big deal is being clean. When you get the pistons out (I used the brake system and it makes a bit of a mess when the fluid can just come out, and, on that particular vehicle there is a single piston per caliper which is not always the case), you have to clean the caliper like you were preparing it for surgery. I did not remove the caliper from the hose as the fittings were pretty corroded and bound up - more twisting and it seemed to me I would be buying and replacing brake lines. So I did the job in the front wheel wells, which made it at least 100 times more difficult.

The only issue with the job is getting the stuff clean, then getting the piston back in the bore with the much tighter, new seal while not disturbing the boot. I liberally applied brake fluid liberally and eventually it went together. No problems since.

If that is all too much trouble, I would get in touch with Benzmac from this site - he is in the area around Atlanta, I believe (Suwanee, GA per his signature data). He can do it or recommend someone who can. In the worst of cases, take BOTH calipers off, cap the hoses and keep your reservoir filled, drain them and ship them to the place in California FEDEX and pay the extra fees to have them FEDEX'd back. The job, even with painting and the like, can't take that long.

Good luck,

Jim

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Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Do fastlane have re-manufactured calipers? I thought some one a few months ago mentioned they had them at a very reasonable price. $200 each is a lot, dont worry about the paint, you can get a spray can of heat resistant paint for a few bucks.

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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

Pretty easy to check with Fastlane if you are curious. I checked for the 1992 500E and they don't. But they do have the repair kits.

For 200 bucks it is not likely they are doing much more than the seal replacement. Painting may be involved but lets not get too excited - it is probably heat resistant Krylon or the like, applied directly from a spray can.

Anything beyond the seal change is not repairable by anyone without some serious investment in tooling, and a local shop to reapply the hard chrome finish to the piston OD and cylinder ID. The tolerance for refinishing hydraulic components, like calipers, is extremely unusual.

Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Just went through this exercise on my '84 TD.
Three weeks ago, drove the car out to visit friends in Haymarket. Had to get on the brakes hard when someone cut me off on the Beltway and noticed some pull. Then, 3 miles down Rt.66 when I needed to slow down again, the brake-pedal went almost to the floor! A few miles later, my brake pedal began to return to normal. I decided to stop at a shopping-center parking-lot in Manassas to check things, and one of my rear wheels was very hot. Made it home without incident and replaced both rear calipers and hoses this week. The old parts appeared to be original and the old caliper-boots were shredded, though the hoses weren't plugged yet.
Rebuilts from Car-Quest were availible same-day for $68 each, plus $18 each for the hoses (and $55 each for the core-charge! Supposedly the wagon rear calipers are special) No problems yet with the fronts, but will check them after this heat-wave breaks.

Happy Motoring, Mark

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DrDKW

Mark, Let me know how this turns out. From what I understand, one wheel locking up is probably a caliper, two is most likely a failing master cylinder. I learned this the hard way.

The good news is I have a sparkling new brake system.

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1984 300D

Many years ago, I had a '72 W115 220. It developed a very peculiar problem. On a long drive, as the underhood area heated up, the brake power assist would gradually dwindle until there was none. Along with this, ALL the brakes would gradually start to drag. The problem went away after the car cooled down, but the cycle repeated during every warmup. In desperation, I removed the brake master cylinder and drilled it's pushrod bore perhaps an additional 1/16 inch. This eliminated the dragging brakes, but the graduall loss of brake assist remained, until I installed a salvage-yard vacuum-booster. Brake performance returned to normal, and the slight increase in brake-pedal travel from my previous master-cylinder modification was hardly noticeable.
In my 40 years working on automobiles, I have never experienced another similar, weird vacuum-booster failure!

Happy Motoring, Mark

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DrDKW

Mark

I wonder if the brakes locking up caused the underhood increased temp. When my rear calipers locked up, engine temp would skyrocket. The engine has to work so much harder with the increased drag.

My problem started with what seemed like just one caliper engaging enough to heat up and smoke. I soon realized that both rear calipers were heating up, just one more than the other. The smell of burning brake pad is unmistakable.

Your drilling of the master cylinder seems ingenious. It's a little above my pay grade though. I bought and installed a new master cylinder, and found it was cheaper and simpler than changing all the calipers. I wonder if the most cost effective method to dealing with two locking brakes is to start with the master cylinder and work backwards to the calipers.

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1984 300D

No. The brake-dragging and loss of vacuum assist didn't start happening until the normal increase in underhood temperature. I suspect that something inside the vacuum booster had cracked and/or shifted enough that heat-expansion caused it to apply pressure to the master-cylinder, and prevent the booster's vacuum valve from operating properly.
It would have been interesting if this particular defective booster could have been sent back to ATE for an 'auto-topsy'.

Something else I learned with this car was why it's preferable to replace calipers in pairs. On a separate occasion, unrelated to my booster failure, one of the front calipers seized, causing the car to pull to one side. I replaced only the one caliper. Then the car started pulling to the other side until I replaced the other caliper.
Now occasionally, I have succesfully replaced or rebuilt ONE caliper, but those vehicles were very much newer than my 220 was when I owned it.

Happy Motoring, Mark

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DrDKW

interesting thread. here's my situation. on my '83 300D, when i apply the brakes the car pulls to the left. so i am thinking the right front caliper is shot. a couple of weeks ago, the right front pads smoked like the dickens. on subsequent drives, the smoke did not return, but the car pulls to the left. i have gathered that the right side pads got toasted and worn down so as not to smoke now. the other thing is that the pedal does not seem firm, and if i pump the brakes when stopping, they are initially firm but then start getting soft and travel almost to the floor.

my conclusion: i must have either a bad hose and/or caliper on the right front. what would you do in my shoes to rectify the problem?

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john
***********
'98 E300 TD "Lukas" 156K
'11 C300 "Mia" 10K, Gorgeous!, Wifey's Car

I'd pull the wheels, and inspect the pads, and rotors. change what's bad.
change the hoses if you have no idea how old they are.

thx vstech. i pulled the right front tire and checked the rotor and pads. they actually seemed ok (not scored or burnt). i went ahead and re-bled the caliper. the fluid was clean. i think i will start with the simplest thing first...replace the hoses and then work from there. the hoses, based on the layers of rust on the fittings, appear to be original. i will update this thread with my results.

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john
***********
'98 E300 TD "Lukas" 156K
'11 C300 "Mia" 10K, Gorgeous!, Wifey's Car

What if only one caliper does not return. Do I just need a caliper rebuild?

__________________
Stuck on older cars
1983 W123 Sedan 300D Diesel Federal

Yeah - a rebuild or replacement would be the next step. There should be rebuilding info in this forum, and hopefully a tutorial. I'll be rebuilding one this week also.

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1984 300D

Section 42-150 in the FSM. Pay attention to the orientation of the piston or you won't be able to fit the heat shield back in, which means your pads won't fit right.

I'd either "score" reference marks onto the caliper or at least dry fit the heat shield in place. I learned the hard way and thought "close enough" was close enough, except it wasn't. Out came the piston a second time...

I messed up trying to remove the lower bolt holding the caliper. Loosy left --- I know but it was the other left duh -- this is the first bolt I have ever broken. I tried an easy out but it was too small and my pilot is not centered. Man I am really f'in this project up. A drunk driver rammed my fence so I have to fixed that instead.

I am bringing the car to the shop instead and I am sure I will be dinged hard, for removing the broken bolt. I already put the left brake pads and that took less than 10 minutes. I had another thread asking this question but this has been really helpful.


Thanks!

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Stuck on older cars
1983 W123 Sedan 300D Diesel Federal