I noticed before I parked my truck I had exhaust coming up from under the hood. My donut on the exhaust manifold need to be changed so I figured it was that. After looking at my carb while it was running I could see exhaust coming up from under the choke. I pulled the carb off and when doing so the two small metal tubes coming off the intake into the carb broke and this is what I found

Now I'm guessing that that hole is not supposed to be there. My problem now besides the broken parts are 35 year old bolts. The bolts holding the part down(wich I have no clue what its called) are rusted and tight. I'm thinking it might be better if I were to pull the intake as well to get the bolts out, and that way I can clean the intake up as well. But I can't seem to get the bolt that hold the distributor loose. Do I need to take the dissy out to get the intake off.

That is the heated choke tube for the carburetor choke. There is tubing that runs from the top, back of the carb, down into the manifold, then back up to the choke. It is a non-electric way to heat the choke spring so it will expand/contract to open/close the choke. See pictures below, which are from my '78.

The bracket next to the choke is for inserting the heater hose supply line, which also aids in heating up the choke. Normally the hose is attached, but I removed it to take the pictures.

I looked for information in the '78 manual but I can't locate them right away.





The insulated line is the line that goes to the choke.

As far as the distributor goes, I don't think you have to remove the distributor to get the manifold off.

And I don't remember if that hole is underneath the chokestove or not???

Thanks, now I'm stuck on the intake. I'm going to pull it off but I can't get it to budge. I think I've got all the bolts out.

If you've got 12 bolts, you have them all. If you can account for 12 bolts, it might take a LITTLE bit of prying to separate the intake.

Do the valve covers overlap the intake ?

78F250SCCS said:

I noticed before I parked my truck I had exhaust coming up from under the hood. My donut on the exhaust manifold need to be changed so I figured it was that. After looking at my carb while it was running I could see exhaust coming up from under the choke. I pulled the carb off and when doing so the two small metal tubes coming off the intake into the carb broke and this is what I found

Click to expand...

Just wondering, looking at the carb mounting surface it looks like there is a crack.

The local junk yard should have that plate and heater tubes for the choke

it's a bit of a pain to replace, make sure to really soak it, those bolts are in there, worse than exhaust bolts to remove because of the diameter.

I've pulled the valve covers already. Was it the norm for the factory to use silicone instead of a gasket on the valve covers. What looks like a crack is stuck on gasket. And if I were lucky enough to come across a 351m in the scrap yard, I'm sure it would look a lot worse than mine. Those little bolts are going to suck coming off. The bolt closest to the fire wall isn't a 7/16 anymore its so rusted away. I'm thinking I might have a better chance talking the wife into letting me buy a new intake and carb than getting those bolts out.

78F250SCCS said:

Was it the norm for the factory to use silicone instead of a gasket on the valve covers.

Click to expand...

No, it wasn't. But, for whatever reason silicone has been substituted for either cork or rubber gaskets. This was usually done to get a warped or distorted valve cover to seal.

The silicone is painted blue on the exposed side. It looks like it was factory. I might have a Edelbrock intake with a 600 cfm holly, what I believe is off a 460 at my dads. He had it one one of his trucks, I thought he traded it for something but he said he got it back, but now it buried in one of his many sheds. He is a hoarder. I have to get all American picker style and go digging for it. Hope he still has it.