Hey everyone,

Ive done a lot of searching and i havent found a good solution to my problem.

Today i replaced my rear driver side caliper since it was seized but had issues with bleeding the brakes. I tried every possible way i knew to bleed the rears but no dice. Including using a vacuum bleeder, pumping brakes, press/hold/bleed/release/close/repeat, and nothing worked. I bled the front brakes easily with no issue.

I decided to trace the lines back up to the abs unit, disconnected the "h" line on the ABS and tried bleeding again but no fluid flowed out of this connection...so im convinced that there isnt a blockage in the rear brake lines.

FYI, the ABS hasnt been working for some reason since i bought the car.

Ive heard about jumping the relay on the ABS but didnt know the exact procedure so theres that possibility. If i was able to bleed the fronts but not the rear, would jumping the relay even solve this issue?

Is the ABS unit shot? Is there a way i can bypass the ABS by connecting the line coming into the unit straight to the line going to the rear brakes? Can i simply replace the whole ABS unit from a donor car at a junkyard?

Need advice!

Thank you very much.

Also, when i attempted to bleed the rears, some fluid did come out but it merely trickled out. Further attempts to bleed just resulted in very little fluid.

When bleeding the fronts, i was able to get a full pedal stroke. When bleeding the rears, i only was able to get a half stroke from the pedal.

Don't know if this relates to your situation. Had a bad master cylinder which caused rear brakes to stick and overheat. When I tried to bleed after overheating, one of the rear calipers had little fluid coming out the bleed screw. Replacement MC solved problem.
In your case, half stroke pedal? Maybe rubber line blocked?

possibly. i havent checked lines coming from the MC to the ABS unit. I got a full pedal stroke when bleeding fronts but only half stoke when bleeding rears since no fluid was even going to the rears to be bled.

Are your rear calipers on upside down? It's happened before.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

fortunately not. wouldnt explain the lack of fluid coming from the ABS though.

Just a thought,
Are you bleeding one wheel at a time, don't know if it would matter's. I bled my brakes the other day and wondered if I could had opened the front and bled them at the same time, closed them off and opened the rear. Ended up I bled one wheel at a time and it worked. Just sayin...

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Collector of Fine Hose Clamps
'77 240D 'AVA' is in heaven now
'80 240D Kanarienvogel
'82 300TD 343k was my daily driver 'ADOLPH' In Surgery for a severe Deer Bite to the Nose
'88 560SL 102k 'White One'

definitely one wheel at a time.

Constructed a pressure bleeder in hopes to solve my brake bleeding woes.

issue resolved using pressure bleeder.

I have constructed everything you have shown here except the master cylinder cap. I bought a replacement MC cap but it has little channels that allow fluid to escape. What did you use for the cap? Where did you get it? Does it have a gasket to prevent fluid loss at pressure?

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Mike Frederick
1986 300SDL, 240K+ miles
1985 300D KaliKar, 270K+ miles

the little channel can be filled in with jbweld-plastic version. then a normal gasket seals it up.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

i bought an ATE master cylinder cap. had no channels to allow fluid to escape. but as vstech said, JB weld is your best bet!

good luck!