Check to see if a rocker arm is compromised on #4. I had a similar problem on mine and it turned out that the rocker was cracked ( it later broke in two).
Or
Perhaps you have a burnt up valve? Bent rod?

Bad ring?


Last edited by Fox; 07/07/2019 6:20 PM.
1970 Chevrolet C10
Grandpa's -- My first truck -- In progress to shiny
Follow the build in the Project Journal
1950 Chevrolet 1-Ton Dually
"Ole Red Girl"
In the Stovebolt Gallery
More pictures here
1951 GMC 9430 1 ton dually--Shiny! | 1972 Chevrolet C20- Rusty- the puzzle box lid for the C10 | 1962 AMC Rambler American- my wife's
Parts trucks-
1951 GMC 9300 | 1951-GMC 9430 | 1951- Chevrolet 1300