1994 E350 Spongy Brake Pedal

[warmblood58]

My indie who is doing the trans swap believes that my abs has issues due to the spongy brake pedal I reported. It appears on vans and trucks that the rear drum adjusters are an issue and can cause this issue. I drove this van all the way home from AZ to Northern California this way, had to pump up brakes a little to get brake pressure and brake travel decreased of course and there was no fluid loss from MC. I think before he starts playing with the ABS that I am going to have him confirm that rear brake adjusters are working and if not, I assume new adjusters are the way to go vs. cleaning. I also understand that the past brake tech could have swapped out the two sides as there is a right and left side which cause adjusters to go out of adjustment quickly. Yes, the ebrake pedal does go to the floor which helps support the idea that the rear brakes are not adjusted properly. Anyone else have this issue with a e350 van? Thanks, hope I do not need to get into the ABS, trans replacement expensive enough!

 

[warmblood58]

Any thoughts Ford brake specialists?

 

[79jasper]

Sounds like you need to replace the shoes and all the hardware.
Might as well do the wheel cylinders also.
And what made a big difference in mine was flushing the fluid.

Look for the ambulance grade shoes.

 

[warmblood58]

Nice, thanks!

 

[OLDBULL8]

Spongy brakes are not caused by the adjusters, it's AIR in the system. It's hard to get the air out of the ABS valve, the way to bleed the ABS is to remove the big nut/plug on the side, there will be a spring and piston come out, remove the spring, put piston back in, install the nut/plug, pump the brakes several times til they feel solid, re-install spring and piston, you should have good brakes then. If not, then bleed the brake system starting at the rear right side, rear left side, front right side, lastly, front left side. If brake fluid was added before, Synthetic does not mix to well with Regular brake fluid. Never mix DOT 3 with DOT 4. Use only DOT 3 fluid for topping off the MC, unless you know for sure what was being used before. After nall of that and you still have spongy brakes, it's possible the MC cups are defective, that means a new MC.

Yes, the ebrake pedal does go to the floor which helps support the idea that the rear brakes are not adjusted properly. Anyone else have this issue with a e350 van? Thanks, hope I do not need to get into the ABS, trans replacement expensive enough!

Missed that. Yes, adjust the rear brakes first.

 

[warmblood58]

Great advice, yes, spongy brakes in my past meant air in the system and a good thorough flush/bleed. I have owned this van for about a year and it lost the trans upon returning home from AZ . . how do I know the PO did not took some messed up brake bleed procedure in his driveway? We will check adjustment at rear drums and will also have system bleed correctly per above. Thanks again!

 

[idi_econoline]

Indeed, warmblood, mine does the same.

Popping off the rear drums to check adjusters has been on my agenda for a while, along with doing the front brakes.

I also get an audible woosh when I depress the pedal. Have on hand a new Motorcraft (=Bosch) vac booster, for whenever I check the brakes.

Fortunately, these issues are less pressing, as my beast is parked with a chuffing exhaust valve.

 

[warmblood58]

So far, van does not seem difficult to work on - my complaint is that the build quality seems weak compared to the '80's Mercedes diesels that I am used to working on - lots of cheap plastic components here and there that can break quite easily, low quality electrical connections, etc. . . oh well

Indeed, warmblood, mine does the same.

Popping off the rear drums to check adjusters has been on my agenda for a while, along with doing the front brakes.

I also get an audible woosh when I depress the pedal. Have on hand a new Motorcraft (=Bosch) vac booster, for whenever I check the brakes.

Fortunately, these issues are less pressing, as my beast is parked with a chuffing exhaust valve.

 

[G. Mann]

For the group on the issue of spongy brake pedal:

I just came across a company that makes an in line check valve that they sell.. one for disk brakes.. one for drum brakes.

In principle, the valves hold pressure in the lines so you don't have to move fluid from the master to the shoes/pads to fill the lines back up.. Their valves hold 2 psi pressure on disk brakes.. and 8 psi pressure on drums.. [their notes say, drum brakes need the higher residual pressure to overcome the brake shoe return springs and leave the shoe "floating almost in contact".

The reviews on the site were all good ones.. went something like "best thing since cold beer and sliced bread.. yada yada''.

I've never used them.. make no recommend.. just wanted to pass them along.. unfortunately.. in the middle of looking at them.. had a computer crash and lost the addy.. I'll try to find it and edit this with the link.

EDIT **** ... FOUND IT... damn computer crashes... Windows version 666 beta... programmed by the spawn of satan.

ANyway... the link to the valves is : http://www.jegs.com/p/JEGS-Performance-Products/JEGS-Residual-Brake-Pressure-Valves/948183/10002/-1

That should give you the full look at what I found.. As I looked at it, thought about the common problems with Ford truck drum brakes in rear and thought.. hmmmm might help..
Of course, regular adjustment is the key.. I took the auto adjusters completely out of my 97 F 250 and just rely on the parking brake pedal position to tell me "it's time to adjust the back brakes". Works well so far.

 

[NO_SPRK]

get hydro boost and get rid of abs... mushy pedal is rear wheel cylinders taking all the fluid so adjust brakes. (unless you really do have air)

bleed with a vacuum bleeder or better yet.. gravity

 

[G. Mann]

I've started bleeding brakes with an electric fuel pump and a 12 volt battery salvaged from a security system.. [little one, like a motorcycle size]... I just hook up the fuel pump to the bleed screw with clear plastic line [hardware store stuff... use it once.. pitch it]

Open bleed port at the longest line [right rear, for example] and suck all the old fluid out.. stop pump..

Switch sides with the pump so suction side is into a clean bottle of fluid.... pressure side is hooked to the open bleed screw... Turn on pump again and watch for clean fluid at the master cylinder, you don't want to fill the master cylinder until you suck out all the old fluid from each wheel and fill the line from the bottom up with the pump.

Close bleed screw at each wheel when you have that line full and added a little fluid to the master cylinder... move to next longest line.. suck out the old.. then pump in clean till get clean fluid, .. watch master, repeat at front wheels.. top off master to mark when all the wheels are full with their lines..

I run about 2 ft of hose on the exit side of the electric pump and dump the pumped out fluid into an old soda bottle... dispose of properly.. [of course]

It makes a totally ONE MAN brake bleed that way.. no fuss.. no muss.. done in 15 min.. always get full pedal...
no spongy pedal with air left in the system
When you push fluid from the bottom to the top [master] air naturally wants to go up.. you always get a full bleed, no trapped air.

Works for me.. try it..