Master cylinder bleeding instructions

1991 FORD AEROSTAR

77,000 MILES • 4.0L • V6 • 2WD • AUTOMATIC

BEANZY98

MEMBER
2 POSTS

Just replaced my master cylinder with a new F19Z-2140-B. The master cylinder has a bleed fitting on it. I cannot find any information regarding the bleeding procedure. Does it have to bench bled or can it be bled on the vehicle via the bleed fitting? Any information would be a huge help.

Jun 18, 2018 at 10:41 AM

STEVE W.

✓Experienced Mechanic
15,330 POSTS

You bench bleed it (on or off car). Then bleed the rear brakes then the fronts. The bleeder will not bleed both sections of the system, it is used to bleed the front pressure switch port that is located higher than the lines.

Jun 19, 2018 at 8:44 AM

BEANZY98

MEMBER
2 POSTS

Thanks for your response. have bench bled master cylinders before but this one had the bleed fitting so I was really unsure. Plus there are three lines because of the RABS. So, one more question please. Would I still have to bench bleed it if I were to vacuum bleed the system?

Jun 19, 2018 at 9:57 AM

STEVE W.

✓Experienced Mechanic
15,330 POSTS

I would simply because of that top port, they like to hold an air bubble. I would also try gravity bleeding it first. Usually does the trick on those because you do not need to mess with the RABS system.

Jun 19, 2018 at 11:55 AM

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