Did you determinate what cylinder which pression miss ?

 

Thanks for the pics! The miss is on cylinder 7. Mechanic only diagnosed down to low compression on 7... really wish mechanic would have done the wet compression test to eliminate issue with cylinder. But I just did a wet compression test and did not compression increase so probably a valve

 

Have you already take look on the rocker ?

 

yes, rocker looks good. Today, started disassembly... broke the tab off the coolant drain plug so that is slowing me down how to drain coolant but other than that, so far so good

 

Pull the bottom radiator hose to drain it then.

 

Keeping in mind that the cooling system will essentially empty itself in about half a second, and it doesn't matter where you put the catch can, the coolant will go someplace else, and end up on the floor, right where you need to lay.

 

Well, if he pulls the end connected to the block, he might be able to control it somewhat by loosening. That's the thermostat housing, btw, so great time to replace it.