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bbrroowwnn

bbrroowwnn

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Hello, I have a 1972 dart with a slant six and I am curious what this round vacuum canister with rod going into the floor of the intake does? It is disconnected as there is no vacuum line hooked up to it.....But when I pull on the rod in and out with the engine running at idle , the idle rpm goes up higher and lower.....does this have to do with the EGR system? where did the vacuum hose originally come from that went to it ? I have no ports open on the carb anywhere....

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Looks like an EGR valve. Exhaust gas recirculation valve
 
alright, so what vacuum line hooks to it? I have charcoal canister still hooked up and no open ports on there....no open ports on carburetor either
 
I've got a '72 factory manual and I can't find a vacuum diagram. They only mention EGR almost in passing but state it comes up through the floor of the intake by an orifice. No mention on an EGR valve but yours sure appears to have one. In 73 and 74 the vacuum for it usually came from the carb, through a temp sensor on the top tank of the radiator and through a vacuum booster before reaching the EGR.

As stated in the '72 factory manual:

"The exhaust gasses are introduced into the intake manifold through jets in the floor below the carburetor. An orifice in each jet allows a controlled amount of exhaust gas to be drawn through by engine vacuum to dilute incoming fuel and air. The illustration shows the configuration used in 8 cylinder engines where exhaust gasses are taken from the intake manifold exhaust crossover passage.

In six cylinder engines, gasses are taken from the exhaust manifold "plenum" chamber located at the "hot spot" below the carburetor riser."
 
Exhaust Gas Regulator, gets vacuum through a ported screw in valve on the intake manifold .If i remember the slant 6,s i had when hooked to vacuum were very noisey when not working properly , prob why it is not hooked up .
 
bbrroowwnn said:
alright, so what vacuum line hooks to it? I have charcoal canister still hooked up and no open ports on there....no open ports on carburetor either
Click to expand...

The charcoal canister has nothing to do with EGR, nor does the carb. The charcoal canister's main purpose is to absorb/store excess vapors from the fuel tank rather than venting them to atmosphere.

EGR, as stated above is exhaust gas recirculation which is used to reduce NOX emissions or oxides of nitrogen from lean air/fuel mixtures.

The vacuum line on the dash pot would likely have been for activation, like when certain criteria are met, a vacuum supply would pull on the dash pot allowing the exhaust gasses back into the intake tract. Not sure which vacuum source it would have been hooked to but I'd bet if you look there is something capped off somewhere close that was supposed to go to that EGR mechanism.

You could also have a replacement engine or something with later equipment and somebody just didn't bother with all the hook ups.
 
thanks for the diagrams......I put a new radiator in it but I still have the old one in the basement and is has no CCEGR valve on it and it is the original radiator .....My 73 dart 340 sport has a NOX valve on the firewall....But my 72 dart swinger slant six does not..... I don't know the slant six engine history if it is original to the car or not....maybe it was changed with a later style slant six.....I know on small blocks above the pan rail on the passenger side it has the VIN number....Do the slant sixes have the VIN stamped on them anywhere? If so, I can check to see if it matches
 
bbrroowwnn said:
thanks for the diagrams......I put a new radiator in it but I still have the old one in the basement and is has no CCEGR valve on it and it is the original radiator .....
Click to expand...
The CCEGR switch is either on the radiator or the thermostat housing according to my 1980 FSM. Mine is on the housing. One port of the CCEGR switch goes to the EGR valve and the other end to the vacuum amplifier (vacuum source). So you could follow all the lines from the vacuum amplifier and see where they go. If your 72 is anything like that of course. :D
 
DodgeLad said:
The CCEGR switch is either on the radiator or the thermostat housing according to my 1980 FSM. Mine is on the housing. One port of the CCEGR switch goes to the EGR valve and the other end to the vacuum amplifier (vacuum source). So you could follow all the lines from the vacuum amplifier and see where they go. If your 72 is anything like that of course. :D
Click to expand...


Yeah, it is not on the thermostat housing either......I am beginning to think this slant came from a later model car.....However, the head is a drool tube head....which I believe they stopped making in 75....so if the motor was changed it must be a 73 or 74 motor....Or somebody just changed out the intake with a more modern one which would be more likely...Anybody know where the VIN number is stamped on the motor?
 
Methinks you have two options, get the EGR going whatever the history may be. That would require a carb with an EGR port and the thermostat housing with CCEGR switch. Assuming you have the vacuum amplifier intact. Also, it looks like some sort of leak at the EGR valve that probably should be dealt with. If you have emissions checking this would be the way to go.

Or they make blocking plates for the EGR valve port on the intake. If it runs good now, removing the EGR valve won't make a difference.
 
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