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Discussion Starter · #1 ·
Once again, I've got a problem with my brakes and once again, I'm conflicted as to where to post this......since it's a 1990 Lincoln Mark VII I drive (not a GM product) :eek:

Anyways.....was driving home from dinner with the parents and the red brake light came on (there is another, yellow one, for the ABS). The pedal subsequently became hard as a rock......I could still stop and everything, it's just I had to really exercise my leg and push hard.....(pedal wasn't squishy or anything like it was when I had my first set of problems)......like the 'power' disappeared from my 'power brakes'.

Now being that it was fine last night when I went to work, was fine this morning when I came home, was fine this afternoon when I was moving cars around in my driveway and has been fine ever since I spent that $780 to replace the pads, rotors and some of the lines.........I'm thinking it's a more common, rather than complicated, repair.....and hoping it's not going to be that expensive.

It could be the pressure control valve.......but I won't be able to look at it until sometime tomorrow when I wake up in the afternoon or whenever.

If, on the other hand, it's a more complicated or expensive piece to fix......this beast is going bye-bye. My dad's convinced that if need be, I can get my money's worth out of this......and being that I'm trying to save up and get my own place......well, you get the idea ;)
 

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Your Mark probably has a Teves ABS system.

This uses a electric pump to drive the rear brakes and power assist. It stores brake pressure in an accumulator sphere to operate the brakes during ABS engagement as well as the assist.

The accumulator sphere is a balloon filled with nitrogen in a metal sphere. The nitrogen leaks out of the balloon into the brake fluid and then eventually it cannot accumulate pressure. They are not terribly costly but is a very easy replacement (like one screw...)

I would imagine this to light the ABS and brake lamps or something like that.

What is the fluid level?



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Discussion Starter · #3 · (Edited)
That might be the answer I was looking for......found a handy .PDF that includes pics of the accumulator & where it's at + tips on how to remove it.....

However, a mod on LincolnsOnline posted this....

The pump simply stopped being powered up.
There is a relay that is operated by a pressure switch to contol pump on/off operations.
The pressure switch turns the pump on when the pressure goes to a low point and turns off on a high limit pressure setting.
You need to look at that part of the circuit for the problem.
Does this sound like it might be caused by a bad accumulator? :confused:

As for the fluid, that was refilled at the beginning of the month (5/01) when I had the pads/rotors replaced, so I wouldn't think it would get too low in a short amt. of time like that.
 

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Discussion Starter · #5 ·
Sometimes when I hit the brake, I can hear a mechanical "whirr" like that, but I have to be listening hard, because sometimes I can hear it and other times I cant.....

I'm tempted to just replace the accumulator though and if that doesn't cure it.......then go knock on my neighbor Larry's door (has a Mark VII stashed under cover in his garage) and ask his opinion....
 
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Have you bleed your brakes? I would start there. Think simple first. When working on cars it's common to want to think the most complex thing first. But start with the most simple thing it could be first. Then go from there.
 

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Discussion Starter · #7 ·
I thought about that........but if the I bleed the brakes then just leave the accumulator in there, it wouldn't take long for more nitrogen to leak back into the lines from said accumulator.......(at least, I think.... ;))
 

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I thought about that........but if the I bleed the brakes then just leave the accumulator in there, it wouldn't take long for more nitrogen to leak back into the lines from said accumulator.......(at least, I think.... ;))
The accumulator leaks into the brakes but this isn't the "problem". It is a very slow leak as the N2 molecules pass through the rubber.

But the accumulator can only store as much pressure of brake fluid as the pressure of nitrogen in the balloon and when it leaks out it can not hold pressure ;)

Normally you should have the pump run at key ON for a few seconds. Then if you repeatedly press brake pedal it should come on again after maybe 8 applications. Classic "dead accumulator" mode is when you press it maybe twice and it starts running. Gas in the lines always shows up as a spongy pedal or a useless pedal (ie to the floor). A rock-hard pedal that is a classic "no pressure" scenario.



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Discussion Starter · #9 ·
Okay.....as hard as it has been to figure this out, I've decided my car is going up for sale here in a bit.....:eek:

My dad & I are going to take it into Woodhouse L/M Monday after he gets off work......and I tell ya, after looking at the big picture, I don't care how much the problem costs to fix......I'll pay it. :yup:

Like I said....have been looking at the big picture and in doing so, have come to the pretty simple conclusion that if I want to move out by the end of the summer....I can't keep pouring money into a ride that, while pretty nice, is nearing the end of it's life.....because once I move out, my income (for now) will preclude any major car repairs.

For it's age (is a 1990, but rolled outta Wixom in October, 1989), the body and engine (5.0L H.O./302 Windsor) are in pristine condition for a ride that has spent most of it's life in the heartland. My dad is pretty confident I can recoup my investment (purchase price + all subsequent service/repairs) and I pretty much agree.....(though the interior could use a tad bit of work..)

I'm taking one thing at a time here though......used car listings change frequently around here and until I get this one fixed, sold and have the money safely in the bank, am not going to even browse autotrader or any of that. :)


One thing I do know is.....(unless a 5th Gen Prelude appears dirt cheap).....my next ride is almost certain to be American :D
 

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Eldo any car is going to require investment in repairs unless it is brand new, but a brand new car will cost more than repairs...

Certainly something like a BMW or Porsche will cost more but a old Mk7 with a 302 and tranny in good shape, assuming the air suspension isn't about to get "rocco hit my knees" sounds about as good as is possible. Especially once you fix the brakes then probably you should be clear sailing...

Doing repair work yourself is a major cost reducer... I'd never be able to be on the road if I had to pay mechanics :D

That said feeding a machine like that with $4+ gas might be more tricky.



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Discussion Starter · #11 ·
Oh I know I'm going to have to fork over money for repairs/upkeep.......but I did make two errors when I bought that Lincoln.....

1) I totally ignored the # of miles it had on there.....which can be a contributing factor towards frequency/cost of repairs. Not to mention the fact I overlooked a number of rides with much less mileage on em.

2) Yeah.....a Bimmer or Porsche would cost more......but I got to thinkin, buying a ride from a 'more expensive' make kind of lends itself to more expensive repairs/upkeep (that thing was nearly $30K brand new)

Also....yeah, you're right about things being clear sailing once I get the brakes fixed.....but to expand on my reasoning a bit more.....the reason I want to start over like this is so I can build up my savings, in the event something major/catastrophic (aside from 'normal wear and tear') happens.

Just have to plan a little bit better this time around ;)
 
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