Alright well over the past 2 days me and a friend eased the manifolds off the head, and put in a new combination intake/exhaust gasket!

I also changed my fuel line from a hard line to a rubber transmission oil rated line with an inline filter, because my old filter started leaking uncontrollably when we hooked it back up ( this has happened before ) and my line nuts were stripped out pretty bad.

Anyways the truck is almost dead quiet from under the hood now! There is only a slight tick at idle, and it goes away when you rev it up. This is much better, especially since the gasket was only 16 bucks and we did it without pulling the manifolds completely or separating them. When I rebuild the motor in the future, I'll take it all apart and get everything perfect.

The truck definitely rumbles a lot more when it idles. I can tell I have an exhaust leak at the muffler now because it pops there at the same frequency that it used to tick out of the exhaust manifold. But now it sounds pretty cool, and when I rev it up it no longer sounds like it wants to fall apart! It sounds very smooth at 2500 to 3000 RPM.

The only problem seems to be that my vacuum reading went from a steady 16 to a steady 15 pounds of vacuum when fully warmed up. I expected it to only get higher, since the intake would be less leaky. Not sure what happened there; but the truck definitely feels like it has more power, so I don't think it's developed a bigger leak or anything.

 

Job well done that gasket is not hard at all to replace as you found out.

Now that you have good sealing manifolds to head get the motor up to temp and adjust the idle speed & mixture as they may have changed.
Also would not hurt to recheck the timing now too.

To tell the truth I have never used a vacuum gauge to set idle mixture or timing.
I may use a tach for idle speed & setting the mixture but most of the time it is by ear.
Timing I use a light.
Dave ----

 

I have a notch on the distributor for 6 degrees, it's at about 7 right now because I still am running w/o vacuum advance. I'll see what it does if I mess with the distributor a little.

I fiddled with the mixture with a gauge connected. The screw is turned way out since I had a vacuum leak, and when I turn it in the vacuum gauge only reads lower values. Didn't try going the other way because I don't wanna take it all the way out of the carburetor.
I may look at this again when I have some time, and I'll make sure it's fully warmed up.

First time I started it after putting in the gasket, I thought it was running on 5 cylinders because of how much it was shaking at idle. It seems to have calmed down some but I can still see the mirrors shaking and I can hear the hood rattling when I'm at a stop. This might be because of the muffler exhaust leak which I can also hear pretty well, at the same frequency it used to tick at.

I'm gonna try to weld up that muffler leak as soon as I can. I just to find someone with a MIG I can borrow.