My girlfriend likes to be tied up with used diesel timing chains.

__________________
DO IT RIGHT THE FIRST TIME, DON'T BE A HACK
Political Correctness is NOT part of my vocabulary
and finally FIGHT CRIME...SHOOT BACK

'82 240D Stick
'85 300D Auto
Drove my first MB at age 16 1960 300SL W190

You're right. I almost forgot about her.......

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

OK, I just made an ultra simple power bleeder. Basically I just drilled a hole in a spare reservoir cap and threaded in a quick disconnect fitting for my air compressor. The plan is to turn the regulator down to 5 psi or so, then just hook it up. My quick test using my mouth as a pressure simulator revealed one problem...when the reservoir is pressurized the pressure seems to leak out of the two buttons on top of the reservoir where the fluid level sensors are. Granted the rubber caps on these are old and cracked on my test vehicle. How did you all get around this problem?

__________________
1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

You use non-cracked and old rubber caps on your reservoir......

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

That will work but you will need to stop often to add more fluid as you bleed the brakes. An external pressurized reservoir of fluid means that you don't have to stop.

ABS brake systems require more than 5psi; I have read they need 20psi but I was able to get by with about 10psi. I was afraid of bursting the reservoir on the car if I raised the pressure too much.

Jeremy

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

Yes, I plan to keep a close eye on the fluid level in the reservoir. I may go to a separate pressurized tank with fluid, but I plan to try this first as it seems to have less of a spillage risk.

So good caps will seal it up fine, huh?

__________________
1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

I just did mine with a home made pressure bleeder with about 10 lbs of pressure. No leakage at all, of course I was using a brand new reservoir.

__________________
Joe

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1980 300SD - 495k miles - 'The Ambassador'
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Former Family Members
95 C280
73 280SEL
90 300D
87 300SDL (X2)
86 560SEL
84 300D
80 300SD

No, not really. I put new caps on and it still leaked. My solution was to remove seal caps and replace with lengths of 1/2" ID plastic tubing secured with hose clamps at tank end and free ends. Looked like hell but I could get the pressure up to 15PSI.

I just used the bleeder, my SD has caps that are in good shape and it leaked a bit, but held pressure enough to bleed the brakes. My regulated compressor idea was a fail, so I made one from a bug sprayer like Jimmy. It worked quite well, but it is still a two person job; I had to have my wife watch the fluid level in the reservoir.

__________________
1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

Hear Here!

__________________
83 300SD, Euro Delivery, Mesa Red, 275k, running strong & quick.

Stop Struggling and get free.

Warning: Over-stroking the master cylinder may cause it to fail.

This can happen to even the most experienced mechanic, "Especially" on a high mileage car.
The old school manual brake pedal "down" - "up" - "down" - "up" bleed method risks over-stroking the master cylinder.
The master cylinder piston seals can get scored if they're pushed into a normally unused - corroded, region of the master cylinder's bore.
If this happens, you'll have little or no brake pedal, and will need a new master cylinder.
I strongly recommend using a pressure bleeder to avoid the issue.

If, on the other hand, one does not have a pressure bleeder...
The method used for a century works if one rule is learned by the person in charge...
THE ONE RULE :::::
*****************************************
It is the person at the bleeder nipple who is totally in charge of the distance the master cylinder piston is allowed to travel.
*****************************************
Be sure to use a brush to get the dirt from the bleeder nipple.
A small hand toothbrush type brass bristle is ideal...

Then open the nipple to make sure it is not stuck. This is WITHOUT any pressure or movement at the brake pedal...
This is just prep so you know what to expect on turning pressure.
Use a solid closed end ( box ) wrench of the proper size for the nipple.
Do not use a ratchet mechanism of any sort because you can not reverse your pressure fast enough.

I have a proper size box end which I have bent to work easier with my hand position.

AFTER THE HELPER HAS DONE A FEW LIGHT PUMPS ON THE PEDAL...
AND IS HOLDING THAT PRESSURE...
THEN YOU OPEN AND CLOSE THE NIPPLE IN ONE MOVEMENT... YOU DON'T COUNT, LOOK AT THE FLUID... NOTHING EXCEPT OPEN AND CLOSE IT. " squirt " that operation is OVER....
If you have planned ahead and do not want any brake fluid in your face ... have placed a clear plastic tube over the end of the nipple and have it in a clear jar on the ground... then you may have gotten an idea of whether a lot of air is present.. not seeing a single flow of just fluid ....and the color or the inclusion of rust or trash.

You have to take your time. Follow the procedure, be sure your helper is trained also. It does not take a bunch of pressure on the brake pedal to do this...warn the helper of that.....
Letting too much fluid out allows the excess travel which Whunter spoke of... which is very bad and TOTALLY YOUR FAULT if you were the one at the nipples...

__________________
1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/diesel-discussion/10414-help-i-need-check-stretch.html

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

******************************************************
It is the person at the bleeder nipple who is totally in charge of the distance the master cylinder piston is allowed to travel.
******************************************************
Sorry to disagree, but the brake pedal pusher has control any time there is no hydraulic pressure to work against.
A simple leg cramp/spasm at the wrong moment.
Umm; Idiot co-workers distracting/playing pranks on the pedal pusher..


The issue just happened to my 1995 E350 yesterday.
I forgot to warn my helper not to full stroke the brake pedal. MY FAULT...
I replaced the Left front caliper and hose = massive air in the system = no brake pedal.

FYI: It has 267,000 miles on it.
Note: This Vehicle has four wheel ABS.

Three good slow strokes of bleeding, and just as the first bubbles formed on the caliper bleed nipple, fluid movement to the front brake system stopped.

Attempted reverse pressure bleed from the caliper, the front brake system reacted as if there was a blockage.
Two hours later.

Pause.
I went through the hydraulic and ABS diagrams.
The only logical answer was, Over-stroking the master cylinder caused it to fail, and block the internal front return ports.

Got a re-manufactured master cylinder $30.00 from O'Reilly auto parts.
By now it was dark cold, and beginning a light drizzle, put off until today.
NOTE: This four wheel ABS required the one with cruise control, even though the vehicle doesn't have that option.

One hour to install the master cylinder, and bleed all four wheels.
Once again it is rolling down the road.

Clearly if one has done other stuff... like emptied a caliper then that would need to have fluid in it...

I was just describing normal bleeding... and on non ABS cars... IS the OP's car ABS ?

"A simple leg cramp/spasm at the wrong moment.
Umm; Idiot co-workers distracting/playing pranks on the pedal pusher.." - Whunter

UH ... I had no way to know I needed to warn against horseplaying in a shop ... a good way for people to get hurt...

I did think to say in the original post.... " be sure your helper is trained " ...... of course that is easier said than done....

__________________
1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

It was not a criticism, just a mild disagreement.
Rule one is 100% accurate for flush bleeding.
After major service, training/education of the pedal pumper is critical.
A very old trick is to put a block of wood under the brake pedal to stop travel at 50%.

I forgot to warn my helper not to full stroke the brake pedal. MY FAULT...
Thankfully the cost was minor $30.00 this time.

Fyi; his E300 may have ABS, don't have time to review the whole thread.

VIOLENT Agreement: Horse-playing in a shop is a quick way to hurt or kill people...




My intent was to raise the awareness of this issue, before it is damaged.
FYI
Warning: Over-stroking the master cylinder may cause it to fail.

This can happen to even the most experienced mechanic, "Especially" on a high mileage car.
The old school manual brake pedal "down" - "up" - "down" - "up" bleed method risks over-stroking the master cylinder.
The master cylinder piston seals can get scored if they're pushed into a normally unused - corroded, region of the master cylinder's bore.
If this happens, you'll have little or no brake pedal, and will need a new master cylinder.
I strongly recommend using a pressure bleeder to avoid the issue.