94 van E-150 AC vacuum control

drob · 06-03-2008, 04:29 PM

94 van E-150 vacuum system

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I've just had a dash vacuum switch replaced because air flow was cutting out when engine load changed. ($21.58 part, $255 labor) Vents are still switching fron dash to floor under engine load change. Have read that vacuum reservoir check valve could be leaking. Can someone tell me how to locate this reservoir and check valve? Also wonder if adding an additional reservoir and check would be an easier option? Could I tee it in , in a location that is more accessable? I'm fairly certain that I could beat the labor cost!

Description: 94/Ford truck/Econoline Van/ Van E-150
VIN: 1 F D E E 1 4 N 9 R H A 0 7 7 1 9

If you want to e-mail me: drobjdm@sbcglobal.net. Maybe pictures could be sent?

Thank you.

captron010 · 06-05-2008, 09:57 PM

I am having the same problem with my 1995 van. Any pictures or location of the tank and valve would help.

phantom_smack · 06-05-2008, 10:05 PM

I added another tank on the inside of the vehicle with another check valve because the original is really hard to get to.I just put it inline= source vacuum/check valve/reservoir then to control head

I might have bypassed the original cant remember.Do you think 98 is similar online manuals only go back 10 years.

captron010 · 06-05-2008, 10:21 PM

Where is the tank and check valve?

phantom_smack · 06-05-2008, 10:51 PM

It has to be in the engine compartment but I cant find a picture of it in the service manual.I would have to folow the balck supply line and trace it out.You could go by the dealership and have them look it up in the parts catalogue and print you a picture.

captron010 · 06-07-2008, 07:37 AM

All they have at the dealership is a generic drawing with no detail.

pcoff61 · 06-20-2008, 09:25 PM

The only thing that worked for mine (2001) was to tee into the brake vacuum line where it comes off the block for a little more suck....I teed into the existing black line in the dash access panel & drilled a snug hole just below the heater control area to get the new line to the engine compartment...it will still drop off momentarily as I accelerate but comes right back when a constant speed is achieved...I never could find a leak or the reservoir people speak of...

drob · 07-11-2008, 08:41 AM

Quote:

Originally Posted by phantom_smack

I added another tank on the inside of the vehicle with another check valve because the original is really hard to get to.I just put it inline= source vacuum/check valve/reservoir then to control head

I might have bypassed the original cant remember.Do you think 98 is similar online manuals only go back 10 years.

Could you email a picture of your new tank? Where did you get your tee, tank, and check?

Thank you,

drobjdm@sbcglobal.net

pcoff61 · 09-15-2008, 10:44 PM

Check valves can be had at most parts stores for about $5.00 I got mine at Autozone... bypassed the old reservoir & the system works fine now.

drob · 10-20-2008, 03:29 PM

I finnally stopped mine from switching. I added a vacuum tank, NAPA part No BK7301605.

I had read about phantom_smack solving his problem the same way. ( Vents switching under engine load and losing vacuum because of a failed check valve.)

Tank cost about $13 and is about 6 inches in diameter, plastic with two nozzles and an internal check valve.( If you draw on the nozzle, without the hood, you will be able to draw air---but you will not be able blow through. This is the nozzle to connect to the engine side.

I removed the inspection cover on top of the dash to watch the valves move. There is a1/8 inch black rubber vaccum line, on the left side of the engine coming out of a block with other lines. There is a connector in the line. First, with the engine idling, I operated the slide control to turn on the air conditioning, and watch the valves move in the dash. Then I pulled the vacuum line loose and operated the slide control again, and when the valve did not move---it was the correct line.

I used another piece of 1/8 inch tubing, about 6" long to connect the tank to the line from the block . Drilled a small hole through the tank mounting bracket and tied the tank under the hood with a piece of wire. Connected the line going to the dash on the other tank nozzle.