What did you do to your Ranger today? (Part Deux!)


I prefer cardboard under my truck when I'm doing major work. 2 layers is best. Especially if the edges aren't in the same spot on each layer and all taped together.
 
I'm going to keep an eye out for some camping style air mattress. I remember as a kid they were heavy rubber? covered with cloth. Always flat in the morning... Lol
I'm not sure if anyone makes those any more. I know the ines ypu're talking about. They were nearly indistructible. We'd pull them out of the tent and go rafting down the creek on them during the day.
 
Ok, riddle me this….

I fixed the AC in the Road Ranger (97 4.0 5spd) a couple years ago and it’s working fine. I think I may have overcharged it a little bit before going to Carlisle, but that’s an easy fix.

When I drive that thing, and I hit the hills, as you can imagine, I have my foot flat on the floor until I go over the top of the hill. Amazingly, I rarely have to downshift, but I do have to put my foot down to the floor.

Well, when I do that, I lose vacuum, and the AC will shift from blowing cold out the dashboard, to blowing warm air up on the windshield. It doesn’t happen quickly. I know from past experience I probably have a little vacuum leak. Here’s the problem I need help with.

I hooked up my Harbor Freight smoke machine to all the little vacuum lines that work the AC and heat system. No leaks. The only place smoke came out a little bit was on the side of this gizmo (idle control?) under that black vent cap, and actually past the air filter where the air comes into the engine.

IMG_7589.jpeg


I’m assuming that’s normal depending on the position of the valves when the engine is shut off.

A little more info. I replaced the vacuum sphere with one of the soup can vacuum reservoirs (2 1/2 times the volume) that you find under the hood of my Towncars and other full-size Fords of the era. Again, no smoke leaking, and I know the vacuum lines back-and-forth are open.

When I lose the vacuum, it happens slowly. Do I just lose the vacuum from the whole engine when I keep my foot flat on the floor like that for a while under load? What’s the solution?
 
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First, you may have a bad check valve. There should be a check valve to hold vacuum in the reservoir when manifold vacuum is low.

Second, when the throttle is wide open, there is little or no vacuum in the intake because the throttle is open to atmosphere.

Third, when the throttle is wide open, there should be a wide open throttle cutout switch (WOT) that disables the AC compressor so it isn't robbing engine power when you need it. So, in addition to the blend doors moving to defrost mode due to lost vacuum, you also don't have the compressor doing its magic to get the air cold. It's a lose-lose situation.

Replacing the check valve may be your solution here.
 
I prefer cardboard under my truck when I'm doing major work. 2 layers is best. Especially if the edges aren't in the same spot on each layer and all taped together.
And works wonders to keep drips out of the underlying asphalt/whatever. Sometimes when I build my redneck garage it comes with a Dollar General box floor.
 
First, you may have a bad check valve. There should be a check valve to hold vacuum in the reservoir when manifold vacuum is low.

Second, when the throttle is wide open, there is little or no vacuum in the intake because the throttle is open to atmosphere.

Third, when the throttle is wide open, there should be a wide open throttle cutout switch (WOT) that disables the AC compressor so it isn't robbing engine power when you need it. So, in addition to the blend doors moving to defrost mode due to lost vacuum, you also don't have the compressor doing its magic to get the air cold. It's a lose-lose situation.

Replacing the check valve may be your solution here.

Thanks, I already replaced the check valve when I fixed the AC a couple years ago, and I also checked it with the smoke machine.

My Shade tree Mechanic common sense is telling me the same thing, that the vacuum just gets lost when the engine is wide open. If I drop my foot off the gas for four or five seconds, it comes back, but that can kill the momentum going up a hill.
 
The Missing Linc has 60-40 w/armrest donor seats from a 1993 extended cab range. I need the driver side, bottom seat, cushion foam, and I can’t seem to find it online. Well, I found one for $400 and I’m not going to do that.

Does anybody know where I can find the foam seat cushion for a 1993 6040 seat? Or what might be an easy swamp with a little modification? I’m looking for the $50 version not the $400 version.

As always, thanks in advance
 
Thanks, I already replaced the check valve when I fixed the AC a couple years ago, and I also checked it with the smoke machine.

My Shade tree Mechanic common sense is telling me the same thing, that the vacuum just gets lost when the engine is wide open. If I drop my foot off the gas for four or five seconds, it comes back, but that can kill the momentum going up a hill.
That's the exact reason the reservoir and check valve are there. They are supposed to hold the vacuum on that sude of the check valve. You have a leak somewhere. Maybe a bad blend door actuator or something in the AC control panel.
 
First, you may have a bad check valve. There should be a check valve to hold vacuum in the reservoir when manifold vacuum is low.

Second, when the throttle is wide open, there is little or no vacuum in the intake because the throttle is open to atmosphere.

Third, when the throttle is wide open, there should be a wide open throttle cutout switch (WOT) that disables the AC compressor so it isn't robbing engine power when you need it. So, in addition to the blend doors moving to defrost mode due to lost vacuum, you also don't have the compressor doing its magic to get the air cold. It's a lose-lose situation.

Replacing the check valve may be your solution here.

What do you think about getting one of these and either running the heater/AC stuff on it, or just tying it into the system on the far side of the check valve, maybe even with a switch where I could only turn it on when I’m climbing a hill?

What did you do to your Ranger today? (Part Deux!)
What did you do to your Ranger today? (Part Deux!)
 
That's the exact reason the reservoir and check valve are there. They are supposed to hold the vacuum on that sude of the check valve. You have a leak somewhere. Maybe a bad blend door actuator or something in the AC control panel.

I agree, but again, I put the smoke machine on it. When I attach the SM to the line going to the dashboard, you can hear the SM motor climb since it’s pumping against a dead end. Every other place I checked from point A point B.

I just had the thought, I’ll check it today with the motor running from the check valve into the dashboard.
 
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That should work. It's a bandaid hiding your leak. But it should work. For reference, diesel trucks or probably any vehicle with turbo or supercharger will have something like that. So, if you're in the junk yard and see something like my 2002 superduty with 7.3 powerstroke, you will find a vacuum pump like that under the hood - passenger side near the rear end of the fender. Although that won't be much cheaper than the $11 one you show above.
 
I just had the thought, I’ll check it today with the motor running from the check valve into the dashboard.
That's where the leak is. One thought; you do have the reservoir on that side of the check valve. Right? Between check valve and AC controls.
 
That should work. It's a bandaid hiding your leak. But it should work. For reference, diesel trucks or probably any vehicle with turbo or supercharger will have something like that. So, if you're in the junk yard and see something like my 2002 superduty with 7.3 powerstroke, you will find a vacuum pump like that under the hood - passenger side near the rear end of the fender. Although that won't be much cheaper than the $11 one you show above.

My 96 7.3 has a mechanical vacuum pump on the front of the engine, belt driven. A little overkill for this problem. Sounds like yours has an electric one.
 

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