I now know that I need to go deeper into the engine to replace the rear cam guide that is broken, but I wanted to spend some more time investigating the valves that may be causing the low compression in Cylinder No. 3 and figure out what other parts I need to obtain.
Before removing the valves, I wanted to remove the carbon deposits in the combustion chamber of the cylinder head. Leaving the valves in during this process ensures that no damage/change to the valve seats will occur if the valves can be retained.
Here is the the current condition of the combustion chambers:
Not terrible after 27,000 miles, but pretty well coated in a layer of carbon. Here are the cleaning tools:
The Mopar Combustion Chamber Cleaner is intended to spray the whole can into a running engine, but it works well with some manual labor too. The Popsicle sticks do the bulk of the work without damaging the aluminum surface of the cylinder head.
After about 45 minutes of spraying, soaking, and brushing/scraping, this was the result:
The cleaning process also confirmed that the intake valve in the number 3 cylinder is not fully seating, as was expected by the increase in the valve clearance measurement for this valve. This was confirmed by the accumulation of cleaning solution in the intake boot that bypassed the closed valve.
Previously I also replaced the gaskets on the exhaust headers thinking that there was a possible leak. Since I have only run the engine for a short period of time since the gaskets were replaced, it was also confirmed by the condition of the gasket for the number 2 cylinder that there is indeed still a leak occurring on that exhaust header.
None of the of the other exhaust gaskets show this discoloration on the trailing edge of the gasket. The gasket is also loose within the port.
Onward to removing the valves and determining if they are still within spec.