Just below the Carter RBS card on my '74 250 there is a second plate that is fairly thick and has a port hole into the intake. The egr is mounted to this and from there a steel pipe (1/2") runs to the exhaust manifold where it threads in. Can anyone tell me what that line is for and how I might find a replacement for it and the fittings?
On 6 cylinder engine, an external tube carries exhaust manifold gases to the carburetor spacer. The EGR valve permitting exhaust gases to flow through the carburetor spacer and enter the intake manifold where they combine with the fuel mixture and enter the combustion chambers. The exhaust gases are relatively oxygen-free, and tend to dilute the combustion charge. This lowers peak combustion temperature thereby reducing oxides of nitrogen. I plugged mine where the tube goes in the exhaust.
Thats EXACTLY what I needed to know Did you also plug the part coming out of the base below the carb? To tell you the truth the tube on my '74 was completely clogged anyways. I guess its not an essential part of the system.
And do you know anything about an even skinnier tube that comes from the driver's side of the carburetor then back around and down to the exhaust manifold? I can't tell how it is supposed to mate up or if it just sits close to a little opening on the exhaust manifold. In your pick it looks like there is a little tube sticking up but no tube running up and over the back. Did you also bypass that?
No need to plug the other end. The valve is closed without the vacuum line. I have a vacuum hose going to my EGR but the other end of the hose is not hooked to anything. I did this 'cause it looked like something was missing and should be there. It might go to the automatic transmission. I had two vacuum lines going to my 6 cyl trans. The trans I have now came with one vacuum line.
If this small tube is connected to the choke...It supplies heat to the choke from the exhaust manifold.This allowes the choke to open as engine temp increases... The tube should be fit into a small hole on the exhaust manifold. They rot off (its common).
thats a bummer about the little line going to choke...on mine it looks like its sheered off right at the manifold. Don't know how to remedy that.
Drill out the broken piece and install a new tube (if you can find one)Or fab up a new one that fits in the hole the way it is now. (There used to be repair kit available for this but dont know if they exist any more)
I was just thinking about the kits we used to buy. Used to get the tube and fittings in the Canadian Tire HELP section. Boy thats a few lifetimes ago.
