exhaust manifold butterfly

On my 223, the butterfly that warms the carb section of the intake manifold is frozen. How does this come apart? I tried pb blaster and heat, I can put a pipe wrench on the counterweight and can turn it somewhat, but I noticed the side that takes the coiled spring isn't moving, and it looks like that shaft is split down the center.
Are there two shafts? Also, I noticed a crack in the manifold under the counterweight area by #4 port. How does it come apart? Thanks, Joe

I was wrong on my original post after thinking more on this and the details in the post by (flatford6) caused me to remember that there are no screws holding the butterfly plate to the shaft it was just pressed on or crimped to the shaft, so have edited the below post to correct the info.

It's one shaft the butterfly valve plate slides into it and was then pressed or crimped to the shaft. With the bimetallic spring removed, the center butterfly plate can be removed by driving the shaft out off it will slide out towards the counter weighted side of the casting, that is if you can get the shaft loose enough so it's turning or moving free again. A small wire bush on a drill motor or by bead / sand basting might get it clean again so it will turn. The compleat butterfly assembly slides off of the two exhaust manifold head pipe studs I think it's roughly 2 to 21/2 inch high. Good luck edited

I was afraid the butterfly was secured by screws, I can't rotate it enough to even see the screws.

Best bet then is to take it off and clean everything good until it moves, or I used to just knock the center valve out of the casting so exhaust flows freely probably not the best if it gets real cold were you live.

I have 2 gallons of used carb cleaner, think that would work if submerged for 3 or 4 days?

It might, the problem is usually caused by years of carbon build up and rust.

If I recall correctly, some manifolds have the butterfly welded to the shaft. probably should check that. Considering the manifold is cracked anyway, maybe time for another manifold. Usually the butterfly is not tight end to end inside the manifold: there is end play in the shaft and after soaking with carbon disolver it can be tapped back and forth until it is loose enough to turn. Then when it is loose enough it can be turned in a direction allowing the screws to be removed if they exist.

Yes your right come to think of it I have also seen some that were spot welded on the shaft. Probably cause when they were loose on the shaft and exhaust flow causes the rattling of the butterfly plate.

Well, I found out why it appeared to be two shafts, when the counterweight end sheared off. I was able to use a drift to punch it out of the manifold, no screws and not welded, butterfly was just a tight fit on the shaft. I found some 5/16 round stock to make a shaft, but I'm hearing to eliminate the setup entirely. What are your thoughts on this?

I used to always knock out the butterfly's on all of mine or completely remove the whole butterfly casting assembly when installing a new exhaust system as I was going for better performance. If you don't live in a very cold area you should be fine, as you can still use your carb choke to warm up the engine. Ford also stopped installing them on the newer models of engines sometime in the latter 1960's or early 1970's. So unless you want to keep it looking totally stock there is little reason to keep it. Good luck

Without the butterfly valve, the area under the carb would be subjected to the exhaust heat all the time, wouldn't that cause some kind of percolating problem?

In the Southern Calif. area I never had any problems without them. The sole purpose of the butterfly valve assembly is to help the engine warm up much faster using the recirculation of the exhaust gas heat, after the engine is warmed up the biometric spring is suppose to be holding valve open to allow the free flow of the exhaust gas and at that point it's not really needed. The stock exhaust manifold still will provide its radiant heat to the bottom of the stock intake manifold since they are bolted together. If you should have any trouble with the carb percolating (it's likely from a different cause) so then you would need to install an insulator or a thick carb base gasket between the carbs base and intake manifold if you don't have one there already and or you could also insulate or reroute the fuel line to bring cooler fuel into the carb. Good luck

Maybe I have it backwards. I thought when the spring was cold the butterfly was open and when the spring got hot it relaxed and the counterweight would drop and the butterfly would close, then upon cooling, the spring would rewind and the butterfly would open.

Yes you do have it backwards when the engine is cold the spring is relaxed and the butterfly valve is closed. Then as the engine is warmed up the spring starts to tighten up opening the Butterfly valve. You could test that by watching the spring as you use a heat source on it and then watch its reaction. Any way the engine performance would suffer drastically with the valve being closed all the time the engine is warm (the exhaust pipe is partly plugged up). I.E. Air and fuel going into an engine has to have a way to get out again.

Thanks, Bubba