My mechanic has my car 8 weeks today
- Thread starter lfeiljj
- Start date
The brake pressure warning switch is located right next to the hydraulic pump motor.
The hydraulic pump motor is the small electric motor, mounted horizontally on the master cylinder assembly nearer the firewall and on the engine side, which turns the hydraulic pump.
The pressure switch is mounted immediately forward, next to that motor. Switch is about an inch long, an inch diameter,. with an electrical connector sticking out.
Maybe use a flashlight and small mirror to see that area. That area is easy to see if you first remove the fluid reservoir.
If Ford doesn't have it and can't get it, the boneyard is where I'm headed.
Call the local auto wreckers or just visit a couple like Pick-n-Pull and search for a Mark 7 or ANY Lincoln from those nearby years.. and bring a few basic tools. Pliers, screwdriver, adjustable wrenches.
From the shop manual: Things you might need..
Reservoir: 4mm Allen head mounting screws
Banjo Bolt: Adjustable wrench
Accumulator: (that spherical ball thing) An 8mm hex wrench fits in it's top
Pump motor assembly: 6mm Allen head bolt (5mm internal hex) The manual recommends an using an extension and an elbow to reach this bolt, but I sure don't recall needing ANY special tools. I guess the junker's engine may have been removed and I climbed into the engine compartment and hacked it all out with a Vise Grip or something..
If you discover you need some other tool, go home and get it.
First look at your own car and pinpoint that switch to figure out what you'll need. (hand cleaner.. and a rag)
A few years ago I needed a new brake fluid reservoir. There's a little internal filter in the very bottom of the reservoir. Mine got clogged up somehow. Brake fluid would not flow.
While getting that reservoir I took a bunch of other parts. including the solenoid valve block, hydraulic pump as well as the pressure switch.
I might have paid about $20 for everything.
Keeping these old cars on the road requires a little extra effort. Or, hire some kid to go get it for you..
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Eight weeks is too long. I already don't like your mechanic. I wonder if he's absolutely positive the switch is bad, or if something else is causing the problem.
(BTW, what is the problem?)
The brake system is simple, but might require a bit of effort to diagnose properly. For instance, a big Lincoln dealer in the SF bay area ran all their tests, could not find the cause of my car's brake problems and gave up on it. They wanted $3,500 to replace everything.. the whole brake system..
The owner gave me the car ('88 LSC) for free. I'm the one who got my hands dirty and found that clogged filter.. $6.
The hydraulic pump motor is the small electric motor, mounted horizontally on the master cylinder assembly nearer the firewall and on the engine side, which turns the hydraulic pump.
The pressure switch is mounted immediately forward, next to that motor. Switch is about an inch long, an inch diameter,. with an electrical connector sticking out.
Maybe use a flashlight and small mirror to see that area. That area is easy to see if you first remove the fluid reservoir.
If Ford doesn't have it and can't get it, the boneyard is where I'm headed.
Call the local auto wreckers or just visit a couple like Pick-n-Pull and search for a Mark 7 or ANY Lincoln from those nearby years.. and bring a few basic tools. Pliers, screwdriver, adjustable wrenches.
From the shop manual: Things you might need..
Reservoir: 4mm Allen head mounting screws
Banjo Bolt: Adjustable wrench
Accumulator: (that spherical ball thing) An 8mm hex wrench fits in it's top
Pump motor assembly: 6mm Allen head bolt (5mm internal hex) The manual recommends an using an extension and an elbow to reach this bolt, but I sure don't recall needing ANY special tools. I guess the junker's engine may have been removed and I climbed into the engine compartment and hacked it all out with a Vise Grip or something..
If you discover you need some other tool, go home and get it.
First look at your own car and pinpoint that switch to figure out what you'll need. (hand cleaner.. and a rag)
A few years ago I needed a new brake fluid reservoir. There's a little internal filter in the very bottom of the reservoir. Mine got clogged up somehow. Brake fluid would not flow.
While getting that reservoir I took a bunch of other parts. including the solenoid valve block, hydraulic pump as well as the pressure switch.
I might have paid about $20 for everything.
Keeping these old cars on the road requires a little extra effort. Or, hire some kid to go get it for you..
------
-----
Eight weeks is too long. I already don't like your mechanic. I wonder if he's absolutely positive the switch is bad, or if something else is causing the problem.
(BTW, what is the problem?)
The brake system is simple, but might require a bit of effort to diagnose properly. For instance, a big Lincoln dealer in the SF bay area ran all their tests, could not find the cause of my car's brake problems and gave up on it. They wanted $3,500 to replace everything.. the whole brake system..
The owner gave me the car ('88 LSC) for free. I'm the one who got my hands dirty and found that clogged filter.. $6.
I originally brought the car in because my brake fluid was pouring out when I stepped on the brakes. It took forever for the mechanic to find the problem. He thought the reservoir had a leak, then he thought it was the master cylinder, etc. I'm not even sure he's right about what it is, all I know is I want my car, it's been sitting outside for 8 weeks.
Raped Ape
Dedicated LVC Member
This may be a long shot but since you state that when you apply the brakes fluid comes out of the reservoir. Well has anyone bled the system to see if the brake system has a considerable about of air in the lines with you witnessing it being bled out at all four wheels?
"..my brake fluid was pouring out when I stepped on the brakes.."
A leak, eh.. A leaking reservoir (or it's hose) would leak ALL the time, engine running or not, and not just when you step on the brake.
So, some area that becomes pressurized only WHEN you step on the brake is the problem. That switch is one of several possibilities in that general area of the master cylinder assembly...
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But a switch is a switch and a leak is a leak. If the switch functions correctly (it successfully detects fluid pressure) then the switch itself is OK. (unless it's cracked somehow.)
Not much can go wrong, or often does go wrong with the pressure switch so a junkyard replacement part is very likely to be sufficient.
If the leak is coming from the base of the switch, be aware that the switch is made leak-proof with a simple O-ring. Assuming the leak IS actually coming from that exact area, the first thing I'd do is replace the O-ring and see if that fixes it.
That switch-area of the master cylinder assembly is very difficult to view and not easy to determine the precise source of a leak. IMO, there is reason to suspect the mechanic's diagnosis might be less than correct.
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But why is this guy hanging onto your car for so long? He has possession and he's responsible for whatever happens to the car while it's sitting out there. And it takes up valuable parking space..
Is there more to the story?
Whatever the case, if I were you, I'd take my recently-found knowledge, and the car, and get a second opinion from another mechanic... even if i had to tow it outta there..
ring... ring...
"Hello. Are you particularly familiar with the '88 Lincoln type of hydraulic pump brake system? No? OK.. thanks anyway."
A leak, eh.. A leaking reservoir (or it's hose) would leak ALL the time, engine running or not, and not just when you step on the brake.
So, some area that becomes pressurized only WHEN you step on the brake is the problem. That switch is one of several possibilities in that general area of the master cylinder assembly...
-----------
But a switch is a switch and a leak is a leak. If the switch functions correctly (it successfully detects fluid pressure) then the switch itself is OK. (unless it's cracked somehow.)
Not much can go wrong, or often does go wrong with the pressure switch so a junkyard replacement part is very likely to be sufficient.
If the leak is coming from the base of the switch, be aware that the switch is made leak-proof with a simple O-ring. Assuming the leak IS actually coming from that exact area, the first thing I'd do is replace the O-ring and see if that fixes it.
That switch-area of the master cylinder assembly is very difficult to view and not easy to determine the precise source of a leak. IMO, there is reason to suspect the mechanic's diagnosis might be less than correct.
-----
But why is this guy hanging onto your car for so long? He has possession and he's responsible for whatever happens to the car while it's sitting out there. And it takes up valuable parking space..
Is there more to the story?
Whatever the case, if I were you, I'd take my recently-found knowledge, and the car, and get a second opinion from another mechanic... even if i had to tow it outta there..
ring... ring...
"Hello. Are you particularly familiar with the '88 Lincoln type of hydraulic pump brake system? No? OK.. thanks anyway."
