walkthrough of my working on my brakes/vacuum system

sgallaty

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i'm learning some things that most of you probably already know, but I figured I'd share as I go so y'all can make fun of me or give me advice as you feel so inclined.

93 E350 cargo base, barn door side, standard body (it's in my garage pics)

symptoms were - intermittent hard pedal, interior CC controls slow to respond. Brake pressure light was not lit.

developed new symptom of left front brake overheating.

observations :

jacked up left front tire and removed wheel, wheel spun freely
left front rotor has smearing from what appears to be foreign material of unknown origin - possibly contaminated pads?
dot-3 brake fluid appears dark and slightly cloudy, smells burnt in the reservoir
removed interior climatecontrol vacuum control line from vacuum tree and hooked up vacuum gauge to vacuum tree.
tested FAIL 5inches at idle, 12 at 2500 rpm that drops to 5 immediately at idle.
tested interior CC vacuum line, test INVALID - holds no pressure using handheld vacuum pump tester (test may not be valid as interior might be actuating baffles)
tested FAIL vacuum with booster isolated to vacuum pump, tested fail 5in at idle.
tested PASS vacuum pump, tested at 25in

observed check valve grommet deteriorated
tested FAIL check valve

replaced check valve and grommet
tested FAIL vacuum with booster isolated to vacuum pump, tested fail 5in at idle.
removed check valve
tested PASS vacuum isolated vacuum pump to booster check valve - 25in.

so, have a bad booster.

questions from this -

is the vacuum warning switch supposed to have a pinhole leak? I can see why it would - that would not really affect the vehicle during operation but would turn the brake light on when the engine quits before the driver puts his foot on the brake. The check valve on the vacuum assist will keep that system depressured.

is the booster a pain to remove?

I'm probably going to swap the booster with an OEM booster from my spare vehicle rather than roll the bones on some chinese knockoff replacement. I find I have better luck using salvage parts than the cheap crap at autozone.
 

yARIC008

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What is brake pressure light? You talking ABS light or tail lights? Also, i dont think your CC has anything to do with your brake problems, thats all electric.

To replace the brake booster need to pull off M/C and other items in the way including CC servo. Bolts attach from the inside. Will have to move fuse panel out of the way to access them, two 8mm bolts for that. New OEM units can be found on ebay, Bendix builds them for Motorcraft/Ford.

Your post was a little hard for me to follow, but if I were you, i'd probably replace front calipers at the least and flush all old brake fluid out. I've never seen fluid so bad that it smells burned. Must have got very hot at some point.
 

sgallaty

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Climate control (cc) appears to be pneumatic.

Brake pressure light I meant vacuum warning lamp sensor. You may be right, it could be the ABS sensor. I will provide a pic when I can - it's between the driver's side battery and the front bulkhead.

is there enough movement to not remove the brake lines to get the MC out of the way to get the booster out, or will I have to remove lines and do a full bleed?

Sorry the post is hard to read, I tried to be explicit with the steps I took to isolate the findings.
 

yARIC008

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Oh, i never seen CC as climate control, only ever cruise control. Yes, in 93 its all pnuematic then wires and levers for heat/cold control. 99% sure there is not enough room to remove master cylinder without disconnecting brake lines, I couldn't do it. They will hit the radiator and high pressure AC line.
 

sgallaty

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Yeah I was just wondering.

I know there are a few very old threads on this but does anyone have a recommendation for MC/Booster combo and where to source it?

Double checked the brake fluid - the burnt smell is residue from the pad, the fluid does not have a burnt smell. It is dark though
 
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yARIC008

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I see a raman on fleabay, dont see any NOS posted now, part number you need is F5UZ2005DA incase you didnt have it already.
 

sgallaty

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I have a hydroboost coming off of an e450 I picked up today but I didn't intend it for this van. I'm building a 4x4 frame-up and the hydro is going on that.
 

laserjock

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Sticky brake calipers are a somewhat common occurrence on fords especially of this vintage although my dad just had one on his 2011 with 19k miles on it. The other thing that can cause a caliper to appear locked up is a bad soft hose to the wheel. If it were me and the fluid looks as you described and I was having issues, I would at a minimum bleed everything and get rid of that fluid. Sounds like you have isolated your vacuum problem. No idea how hard it is to change on a van but booster is not terrible on a pickup. Just have to be careful of the brake lines not to kink or break them when you pull the master off the front of the booster.
 

sgallaty

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I dismantled everything and am about to take off the caliper and shoe housing and regrease those two 21mm bolts that the caliper slides upon.

I also need to determine if these rotors are salvageable. they seem to have foreign material on them, and are a little gouged.
 

Thewespaul

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Replace the rubber brake lines that lead from frame to caliper if they appear dry rotted or just not new in general, those caused my new calipers to stick and kill my new pads and rotors in days.
 

sgallaty

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is there a place to get some steel braided reinforced lines? If I'm going to replace them I might as well upgrade it.

All of the rubber on my 93 is deteriorating badly.
 

Thewespaul

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is there a place to get some steel braided reinforced lines? If I'm going to replace them I might as well upgrade it.

All of the rubber on my 93 is deteriorating badly.

Yes but they are meant for lifted trucks so they come with 6 inches of extra length and are almost $100 a piece :puke:
 

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