Heater control valve issue in a 1997 Aerostar with A/C.

[Old Tom]

1st timer here and am hoping you all would have some insight for me in regards to a heater control valve.

A little back info on the situation.
I have had a persistent slow coolant leak for a few weeks now. After some trial and error, I managed to locate the leak to the heater control valve. Not much of a surprise that it was broken/leaking. Its factory original and is 14-15 years old, so not too upset that it finally gave up and cracked on a hose nipple and started leaking.
So i manged to remove it. It was on the passenger side over close the to fender and close to what im assuming is the A/C evaporator or some such A/C piece.
So i found a replacement part at my local auto parts place for like $18. Not too bad i thought.
So here is where we get to the puzzling part. While the replacement part looks the same as the old part, if i look at the design of the 2 parts and line them up accordingly, the vacuum valve assembly is facing the opposite direction from the original and thus getting a hose clamp of either the tension variety or the screw down kind is all but impossible.
So i thought that maybe i received the wrong part. So i did some online checking for heater control valves for my van and all the pix show the same part with the vacuum body facing towards the rear of the vehicle.
Is this right? Reason i ask is the old unit had the vaccum valve facing forward. Getting clamps off/on that is difficult but is doable. Where-as this new part . . . .i can get it in place but there is no way to get to the hose clamps to tighten them down.
Is there something Im missing? Do i indeed have the wrong part? Can i flip the vacuum valve around without causing any coolant flow issues? I will attempt to take some pix of my situation and post them here to see if that will help with both my explanation and hopefully a solution.
thanks
Tom

 

[Old Tom]

pictures

here is the old part prior to starting to remove it. Notice the vacuum assembly is facing towards the front on the right of the heater control valve. the vaccum assembly is partially blocked from view by the A/C line in front of it.
For reference, the upper left corner of the air filter box is in the lower right portion of the image. All of this is on the passengers side of the van.

here are the 2 HCV's together. The old one is on the left. The lower hose nipple disintegrated pulling the hose off. So to say the least, thats where the leak was coming from.
Notice how the vacuum assemblies are facing opposite directions if you orient the parts in the same manner. I assumed that the directional arrow on both units on the bottom pointing up show coolant flow direction. Hence why i aligned them by the arrow and the likeness of the overall construction.

Here are 2 pics of each valve(old 1 1st). The inside flapper is in the same orientation inside both housings.

And again, every single google search or the like for a replacement HCV for this 1997 aerostar show the exact image of the item i purchased.
So a couple thoughts come to mind. Do i install the new part in its matching orientation to the old 1 as shown here in the pics? Or do i flip it over so that the vacuum assembly is facing forward? Will doing that flip cause operational issues with the flapper inside? Or do i have the wrong part regardless of what the parts store shows and the entire internet says i should be able to install as a replacement?

Do appreciate any assistance or insight.
thanks
Tom

 

[BrooklynBay]

Welcome to this forum! It shouldn't be a problem just as long as there is no internal check valve.

 

[Old Tom]

thanks for the welcome! appreciate it!

it appears that there is a check valve in there. Im assuming your meaning of a check valve being a flapper to control flow direction of the coolant? Because what is inside the housing and is controlled by the vacuum assembly appears to be some sort of metal flap set at an angle. And when you push the vacuum plunger, the control arm moves that flap to the opposite angle.
I know just about enough to be dangerous on this kinda thing. Id much rather rebuild a motor than deal with these small issues

 

[BrooklynBay]

A check valve allows the flow of coolant in one direction only. Check to see if fluid could flow both ways when it's open.

 

[Old Tom]

will check into that. Ive been staring at this most of the afternoon to see if im missing something. Im hoping i can flip the entire unit or just unscrew and flip the vacuum assembly. But decided to step back and see if someone with more experience than me had some insight before i just charged forward and potentially do more harm than good.

Time for dinner. It can sit til tomorrow afternoon. Certainly not going anywhere in its current state.

Thanks for your input. Much appreciated.

 

[TaylorYancy]

I'm wondering if the vacuum opens the flow of water or closes it? My vacuum line is leaking and basically I want to know if I should replace it now so the a/c isn't fighting against it or if it can wait until the fall when I will need heat again.

Cheers

 

[BrooklynBay]

Welcome to this forum! The valve is designed to prevent the flow of coolant while the A/C is on so it should always be closed unless there is a call for heat.

 

[speleopower]

I replaced mine last year and I had to unscrew the vacuum control piece and screw is back on in the opposite direction. No check valve that I know of and you just have to kinda reroute the vacuum line a little and don't reattch it to the side of the engine compartment. Mine has been good to go for quite a while. Let me see if I have a picture.
Nope I don't see a picture. I thought I posted a picture of mine last fall.
-Scott

 

[asavage]

Welcome to this forum! The valve is designed to prevent the flow of coolant while the A/C is on so it should always be closed unless there is a call for heat.

I don't think that's correct.
In A/C mode, one can move the temp knob to get dehumidified, warm air.

I'm pretty sure that the no-vacuum mode of this valve is to route coolant to the heater core, and that vacuum is applied to bypass the core.

-----------------------------
Another member recently had the same problem on his '95 with dual-heat. Here's a good picture of the problem: the vacuum servo hits the filter/drier strap, and he said that he could not re-mount the vacuum servo 180°.

(click on any image for larger)

Here's a pic of my '97's:

And, this is the valve on eBay that the other member bought and found fit well:

I just decided that I'd better go buy one myself and stash it, if it's going to be this much trouble to source one that fits on short notice. These plastic heater control valves do break!

 

[BrooklynBay]

Check this thread for more information: http://www.explorerforum.com/forums/showthread.php?t=190431

 

[asavage]

While that thread has interesting info about adding the Four Seasons 74809 Heater Valve to a rig that has no heater shutoff, that valve that shamaal installed (the 74809) has the same configuration as the one that Old Tom is fighting.

(click on any image for larger)
shamaal's 74809 on left, Tom's on right:

So the Four Seasons 74809 isn't a fix, unless it can be mounted differently, or the vacuum servo can be re-mounted 180°.

I was at the JY yesterday, took a couple of pics.

The '94 Explorer pic has the style that I've got coming from that eBay Seller, but the online replacement from "anybody" is the 74809-style.

From what I can find, the same Motorcraft YG-350 and Four Seasons 74809 are presented as the replacement valve for a lot of Ford applications. And, for almost all application, it fits.

But not for Aerostar.

I have spent a couple of hours trying to find another source for the eBay one I've got coming, to no avail.

 

[BrooklynBay]

Did you check WWW.RockAuto.Com or WWW.TousleyFordParts.Com?

 

[asavage]

I checked many, many years of various Fords at RockAuto, yes.

I looked at every heater control valve at NAPA (all brands).

I just checked out TousleyFordParts, and they tell you nothing about any valve they offer: no part No., no picture.

 

[asavage]

Here's the unit I just received from the eBay sellers:

(click on any image for larger)

This looks like a good replacement for the factory installation valve. Now, if only I could find a way of ordering it via a part number.

 

[BrooklynBay]

Is there anything written on it to figure out who makes it? How much was it?

 

[asavage]

The metal vacuum servo has "3MB" stamped on its bracket.

It was $14 shipped.

I've asked the Seller if they can provide any part No. info.

 

[bearbait]

This is the actual heater valves Ford used early on. These were bought from a Ford factory that closed. You can not buy these anywhere that I know of. All the manufacturers use the cheaper all plastic valves now. When I run out of these that will probably be the end of them. I have discussed this with a Motorcraft rep in my area. I have owned an auto parts store and was a trained Ford mechanic and have not seen these valves from any supplier for years. Thanks, Steve

 

[asavage]

(member bearbait is eBay seller bestdeal120)

I'm getting confused. Let me take another stab at this.

A couple of pictures of the factory-supplied valve. Note that the vacuum servo is inboard (on the engine side of the valve), is parallel with the ground, and its nipple faces forward toward the grille:

(click on most images for larger)

The replacements listed have the vacuum servo pointing at an angle, toward the rear:

As the hose connections are all the same size, can't we just rotate the whole shebang 180° ?

Failing that, it looks like the vacuum servo on at least some of the replacement valves can be unscrewed. Can't we re-mount the servo 180°, like Scott did?

 

[asavage]

I found an Aero in the JY yesterday with one of the Motorcraft/Four Seasons style heater control valves fitted. As I suspected, rotated around: