I have been rebuilding my brake calipers for quite some time. I finally have things back together. In the process I replaced the master cylinder with a Ford aluminum version that I know many of you have.
Before you ask, yes the brakes have been completely bled. All the seals have been replaced including in the master cylinder. The issue is that the pedal must be pushed a fair amount before the brakes engage. Is this normal for this master cylinder?
Steve
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I have a similar problem. Your push rod may not be adjusted properly. I'd like an explanation as to how to know where to set it. It should be maybe 1/16" or so between it and the bore surface?
I followed the instructions in the service bulletin. I’m at work so I don’t have it in front of me but there is ~0.040” clearance between the adapter pushrod and the piston in the master cylinder if I remember correctly.
How did you measure it since you can't unless it is installed?
First I set the length of the pushrod long then mounted the MC but did not tighten the bolts. The bolts only hold the MC in place. Then using feeler gauges top and bottom (it takes 2 sets) I measured the clearance between the MC and the adapter. Then I removed the MC and pushrod from the booster. Measured the pushrod with a digital caliper and reduced the total length by the feeler gauge measurement plus the additional specified clearance, again I think it was ~0.040”.
Steve
Okay, got it. So still the question is why the excess pedal travel. I don't like the feeling at all.
Agreed, the pedal feel does not inspire confidence. That’s why I asked the question to see if others have had a similar experience. The MC is new to me but I put a rebuild kit in it so I know it is good. The bore is 15/16” and now I’m wondering if I should go up to a 1” bore to get a better pedal feel.
Steve
I don't think that little bit extra would help much, you would be pushing more volume, and the effort should be a little less, but don't know about travel improvement.
Yes, MC was bench bled first using this
Then we worked from the furthest away in order. I'm pretty sure it is not air in the system. I larger MC will move more fluid with less travel but will give up some mechanical advantage. I'm wondering where the sweet-spot is for MC bore size? Or, would residual valves in each circuit make it better?
Steve
Maybe try preload instead of clearance. I recently installed the same master cylinder on one of my cars and it is working well with about .010" preload. Peddle travel is minimal and the brakes do not drag when everything is heated up. It is best to disconnect the lines from master cylinder when making this adjustment. I removed all of the fluid from the reservoirs to minimize leakage. Setting preload is easy because you are simply checking the gap between the master cylinder and the booster. Once the lines were reconnected and reservoirs were refilled I did not have to bleed the system.
So do you guys know the original application for these master cylinders? what part number do you use to order them?
Did you get them through a vendor? What do they cost?
Thanks -
Rocky
I got one on eBay in February for $19 shipped. The part number is:
2229331 Brake Master Cylinder
These are remanufactured Bendix master cylinders that were used on various Ford models.
You will need an adapter in order to mount it, such as the one from Ipsco:
https://ipsco.org/newsite/prod...ake-booster-adapter/
Also, the stock Pantera brake line nuts at the master cylinder are metric bubble and the Ford master cylinder is standard flare. You will need adapters or you can make a new pair of the short lines that connect to the shuttle switch block. Since I have all of the materials on hand I did the latter, and put the stock lines in the box of spares in case I can find a good reproduction master cylinder. I have had a problem with the reproductions leaking at the reservoir grommets.
