Well I made a bit more progress. I hit the dreaded spinning body cage bolt, so now I am waiting on my compressor to come in so I can cut a couple of access holes. I have been finding more and more rust, but still not as bad as some of them I have seen. I have a couple of questions:
What is this piece on the Header? It is spring loaded it feels and looks like some sort of butterfly valve:
And this is where she stands now:
1976 CJ5 Bone Stock (gone but not forgotten)
1973 C104 Jeep Commando (My Brothers)
1998 XJ Currently Stock
2009 F150 4x4 FX4 Screw
Last edited by Project76; 10-24-2008 at 06:41 PM..
That is the Exhaust Manifold Heat Valve. It starts out in a closed position and as the engine warms up it opens.
From my FSM:
"A thermostatically controlled heat valve mounted between the right exhaust manifold an exhaust pipe directs exhaust heat to the intake manifold for rapid fuel vaporization during engine warmup. The valve is closed, directing exhaust heat through the intake manifold crossover passage when the counterweight is in the horizontal position. The exhaust heat crosses through the intake manifold and discharges into the left exhaust manifold until the engine reaches operating temperature. At this time, the thermostatic spring loses its tension and the counterweight moves downward, opening the valve and allowing the exhaust heat to discharge through the right exhaust pipe."