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Topic: Where is the MVAC vacuum reservoir supposed to go? (Read 3934 times) previous topic - next topic

Where is the MVAC vacuum reservoir supposed to go?

I went to install a JY MVAC vacuum reservoir in my '85 Cougar tonight only to find there seems to be no place to attach it. I fixed the reservoir on my '87 T-bird last week....are '83-'86 cars different from '87-'88 in this regard?

'87 Thunderbird



'85 Cougar


Notice there are is no slot for the left-hand side and no screw hole for the right.

Where is the MVAC vacuum reservoir supposed to go?

Reply #1 –
There is a hard to interpret drawing in the '84 EVTSM. I think it is somewhere under the right front fender.

Where is the MVAC vacuum reservoir supposed to go?

Reply #2 –
above the ac dryer were do the vacume lines go to from the vacume check valve?
One 88

Where is the MVAC vacuum reservoir supposed to go?

Reply #3 –
The reservoir line ran into the fenderwell, but the line was closed off at the end. When I took off the splashguard, there was no reservoir to be found.



This picture shows where the first picture [of the T-bird] was taken. The oval shows where the vacuum line went through. The two arrows are where the mounting points are located on the T-bird.

Where is the MVAC vacuum reservoir supposed to go?

Reply #4 –
well jeremy does the dash change the positions its blowing out of when you drive?  if not then why are you installing it?
One 88

Where is the MVAC vacuum reservoir supposed to go?

Reply #5 –
During low vacuum maneuvers (going up hill, passing) the air defaults to the defrost. It is more annoying than anything.

I'll just drill some pilot holes and put it up with some sheet metal screws.


PS The car was wrecked on the right side sometimes in '88, which is why I think thinks aren't as they are supposed to be

PPS I hope the shop/person who fixed my car after it was wrecked is raped in the ass by rabid gorillas with giant horsepen 15s and then tossed off a cliff onto white hot razor sharp spikes. Except I hope they live long enough to be eaten alive by vultures.

Where is the MVAC vacuum reservoir supposed to go?

Reply #6 –
Quote
I hope the shop/person who fixed my car after it was wrecked is raped in the ass by rabid gorillas with giant horsepen 15s and then tossed off a cliff onto white hot razor sharp spikes. Except I hope they live long enough to be eaten alive by vultures.

Tell us how you really feel, Jeremy. ;)

OK, I'm really reaching back into the ol' noggin here but I do recall that on some of the early engine bay configurations, the vacuum ball could be on the driver's side. At the boneyard once, I saw a vacuum ball by the cruise control servo, and it looked factory to me. I guess the easiest way to figure it out would be to follow the single skinny line that comes out of the firewall by the heater core, and follow it wherever it goes. If it goes to that tee you have pictured then somebody did something funky. That particular connector should be under the hood, not creeping down into the fender like that. It's possible that someone bypassed the vacuum ball entirely, and that you have no reservoir at all, and the entire climate control system is working off of available vacuum from the a/c connector line (vacuum tee by the wiper motor). I suppose that *could* work but not as efficiently as originally intended.

As for the missing holes to bolt that up, there was an inner fender structural change in 1986 to accommodate that vacuum ball on the 5.0, and I think Ford just used the same for the 3.8 too. How good are you with zip ties? ;)

Where is the MVAC vacuum reservoir supposed to go?

Reply #7 –
I tracked it down on my '84 T-Bird. It is on the outside of the fender apr0n adjacent to the battery. The vacuum tube goes through a hole below the throttle body air inlet hole. The slot for the slide-in end of the mounting is to the front and the bolt hole is to the rear.

The drawing in the EVTSM shows the vacuum going to the bolt hole side of the tank. This the reverse of your picture. If the mounting is removable from the tank maybe you can turn it around.

Where is the MVAC vacuum reservoir supposed to go?

Reply #8 –

Slide in on the left, bolt on the right, battery box on the bottom.

Where is the MVAC vacuum reservoir supposed to go?

Reply #9 –
Thank you for that post. I would have never have found it. The reservoir has a symmetric base, so it mounted up just fine.

Where is the MVAC vacuum reservoir supposed to go?

Reply #10 –
Jeremy, just for a little closure I checked the part numbers for that area of the car from which you took the photos. Technically Ford calls it the 'apr0n'. These are the p/n's for the entire apr0n assembly that includes the upper and lower crossbeam supports:

Apr0n Assembly w/Sidemember
1983-85 R - E5SZ-16054-A
1983-85 L - E7SZ-16055-A
1986 R - E8SZ-16054-A
1986 L - E7SZ-16055-A

Now here's where it gets interesting. These p/n's are just for the apr0ns themselves, which basically amount to the sides of the engine bay, sans the top and bottom supports:

Apr0n, Front Section
1983 R/L - E3DZ-16054/5-B
1984-85 R - E4LY-16054-B
1984-85 L - F0ZZ-16055-B
1986 R - F2ZZ-16054-B
1986 L - F0ZZ-16055-B

Note the ZZ in the part numbers...ZZ is Ford's code for Mustang-designed parts. Therefore, this is confirmation that our 'apr0ns' are identical to those used on Mustangs, and anything that fits a Mustang in that part of the car also fits our cars. So, say you need a new apr0n for the passenger side of a Cougar...it cross-references to a 1992 Mustang part.

Anyway, you can see that there was a change between 1985 and 1986 and that explains your photos.