81 Imperial Brake Problem/Question.

[jmr]

Question for you guys.....

My Dad has owned a '81 Imperial for about 10 years now. The car was converted to a 2 bbl carb from EFI by the dealer back in the day when he first bought the car. His complaint since he bought the car is with the brakes feeling mushy requiring allot of pedal travel to really activate them, like air is in the lines. The rear drums are fine and in adjustment but the Imperial has had the front calipers, front brake lines, proportioning valve, master cylinder and power brake booster replaced and of course blead on many occasions. We even changed the power brake vacum source from the carb base plate to the intake manifold.

When you apply the brakes the nose will dive but it takes allot of pedal movement to do that. If you double pump the brake pedal the brakes seem much more responsive (like having air in the lines but there isn't any). If the brake pedal is slammed it will stop but the wheels don't lock up super hard.

So my question is this normal? Is this how the brakes feel with these cars?
I don't know anyone with a similar type Mirada/Cordoba/Imperial to compare these brakes against.

Thanks in advance. Jim.

 

[Shorty Thompson]

you got drum brakes on the diffy ? If so adjust them out till you can barely turn the wheels . That should solve your issues .

 

[ramenth]

you got drum brakes on the diffy ? If so adjust them out till you can barely turn the wheels . That should solve your issues .

I agree with the adjustment of the brakes helping.

Everything is moving right? The way the pads rest on the anchors on these cars the pads have a tendency to notch into the anchors. If the anchors aren't smooth so the pads can move properly the pads rest in the notches and give a "false" pedal like you're talking about. It usually takes a couple of hard pushes of the pedal to get 'em to squeeze the rotor right.

I've posted this on other forums. Use brake lube! Not anti-seize, but actual brake real life brake silicone. It comes in the little packets at your preferred parts store, usually at the counter. You can buy it by the tube from Loctite, NAPA has a synthetic brake grease (although I don't like it, it's better than a dry anchor). I buy mine from Ford. Motorcraft #XG-3-A. You can buy it by the tube from Mopar, too, though the part number escapes me at the moment.

The silicone won't wash off in hard rain, stands up to salty roads, absorbs sound and stays put even in the tightest of clearances.

Put a small smear on the anchors where the pads need to move. If your daily driver has calipers held on with pins, put some on the pins, too. In the case of this Imperial, like all of our F/M/J's (and Y's) put some where the caliper rides against the anchor, too. Put some on the threads of the adjusters on rear brakes. Those little pads on the backing plate on drum brakes are called shoe lands. The shoes rest and move on these. Put some silicone on those, too.

When everything is moving right it'll give you a nice firm pedal right up until the day you need brakes again.

 

[jmr]

Yes it has drums on the rear axle. The rear brakes drag very lightly right now and it sounds like they need more drag to work correctly. I'll check into the silicone brake lube too.

Thanks for the help.

 

[Shorty Thompson]

rear brake adjustment is crucial to proper pedal height . Learned that the hard way .