Is heated air same as manifold vacuum?

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gdizzle

gdizzle

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So on my 66 dodge slant, running the super six setup with Carter BBD. I have 4 ports that I capped off. I also have a tube running directly off the intake manifold connected to the Air filter thermostatic dingus.

I want to just plug the manifold intake port (on the manifold) and connect the thermostatic dingus to one of these 4 ports on the carb. Any idea which ports I can use? I believe the lower 2 are heated air. Does that mean manifold vacuum? the other 2 is for egr thingy, and a purge thing, neither of which I have.
see pics.
ports - 1.jpg
ports - 2.jpg
 
Heated air is not manifold vacuum. Heated air comes from the exhaust manifold. Not exhaust gasses, but hot air off the manifold itself.
 
...and WTH is a thermostatic dingus?
 
hey RRR, the dingus is that flapper thingy that opens (or closes) the air intake hose connected at the heat stove on cold mornings. it needs vacuum to push down that flap, then as it heats up, the flap rises back up.
 
gdizzle said:
hey RRR, the dingus is that flapper thingy that opens (or closes) the air intake hose connected at the heat stove on cold mornings. it needs vacuum to push down that flap, then as it heats up, the flap rises back up.
Click to expand...

Where did you learn it needs vacuum? If you are talking about the flap in the exhaust manifold, it does not require vacuum. It has a weight and bimetal spring. As the spring heats up, it allows the flap to open.
 
It is generally controlled by a vacuum switch on the intake or thermostat housing. When the coolant temp gets high enough it switches the door on the air cleaner to fresh air instead of exhaust heated air. On a slant it may be installed in the block but always in the coolant path.

An early slant may never have had such a arrangement, but I am a BB guy and do not even remember such on a BB pre 70.
 
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The man is asking about how to hook up the thermostatic air cleaner. The answer is that the air cleaner temperature sensor (the flying saucer-lookin' thing on the floor of the air cleaner housing, visible by removing the air cleaner lid, with two nipples sticking through the underside of the air cleaner housing) gets one of those two nipples hooked to manifold vacuum, and the other goes to the vacuum actuator on the air cleaner's snorkel. Any source of unrestricted manifold vacuum will do, but the carburetor nipple (present on '70-up carbs) identified as "heated air" is the one intended to supply vacuum to the air cleaner temp sensor; carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download.

The system is described in detail here, for those who think it's controlled by a vacuum switch on the intake or thermostat housing, or confusing it with the manifold heat control valve located in the exhaust manifold, or otherwise bewildered.
 
slantsixdan said:
The man is asking about how to hook up the thermostatic air cleaner. The answer is that the air cleaner temperature sensor (the flying saucer-lookin' thing on the floor of the air cleaner housing, visible by removing the air cleaner lid, with two nipples sticking through the underside of the air cleaner housing) gets one of those two nipples hooked to manifold vacuum, and the other goes to the vacuum actuator on the air cleaner's snorkel. The carburetor nipple identified as "heated air" is the one intended to supply vacuum to the air cleaner temp sensor; carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download.

The system is described in detail here, for those who think it's controlled by a vacuum switch on the intake or thermostat housing, or confusing it with the manifold heat control valve located in the exhaust manifold, or otherwise bewildered.
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My apologies, as a general mechanic the other brands did this with a coolant switch. Like said I am no slant expert and have never dealt with this in BB land with pre70 Mopars as all mine were high performance models. Please excuse some of us as we just offered a suggestion and not fact! Have a wonderful T’Giving!
 
Coolant temperature switches were used for enabling/disabling EGR systems in many systems, and vacuum spark advance in some systems, but they were not used to control thermostatic air cleaners—by any automaker. That's because the relevant property is the temperature of air flowing into the carburetor, not the temperature of the engine coolant. Aside from some early Ford setups in the late '60s that used a wax pellet (like the one in the coolant thermostat) acting directly on the snorkel door, thermostatic air cleaner systems were all very similar regardless of brand. The AC thermo sensors GM used looked a little different to the Fram sensors used by Chrysler, Ford, and AMC, but they all worked and hooked up the same way.

Happy T-day to all.
 
When people use really technical terms like "dingus" that's what's bewildering, Dan.

Sorry we missed it. And thanks for yet another condescending correction.
 
Glad to serve. What's really important is that RustyRatRod's feelings don't get bruised. I should not have assumed the OP wants to get the info he needs to fix his damn car (correctly) and get on with life; it's possible he asked his question in hopes of being sent on needless goose chases under his hood. I should have thought of that. Thanks for reminding me; I'll try and do better next time.
 
slantsixdan said:
Glad to serve. What's really important is that RustyRatRod's feelings don't get bruised, not whether the OP gets the info he needs to fix his damn car and get on with life.
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It's not about feelings. I don't throw barbs at you out of respect. It's nice to get the same treatment.
 
RustyRatRod said:
I don't throw barbs at you out of respect.
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I don't care why you throw barbs at me, nor do I particularly care that you throw barbs at me, but I do throw 'em back from time to time. Wanna quit? OK by me, let's quit! Startin' here, startin' now, no more barb throwing and backthrowing between RustyRatRod and SlantSixDan.

happy23.gif


happy23.gif
 
Pretty sure that Barbie throwing will still happen between the two of you.
 
gdizzle said:
So on my 66 dodge slant, running the super six setup with Carter BBD. I have 4 ports that I capped off. I also have a tube running directly off the intake manifold connected to the Air filter thermostatic dingus.

I want to just plug the manifold intake port (on the manifold) and connect the thermostatic dingus to one of these 4 ports on the carb. Any idea which ports I can use? I believe the lower 2 are heated air. Does that mean manifold vacuum? the other 2 is for egr thingy, and a purge thing, neither of which I have.
see pics.
View attachment 1715112643 View attachment 1715112644
Click to expand...
The answer is yes, use a tube on the carb that is manny vacuum to the thermostatic switch on the air cleaner housing, that is the way it is supposed to be.
 
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