5.9 One of my valve springs broke

Here is one of the old trick: -remove the spark plug, put that cylinder to TDC and feed a long rope through the spark plug hole as much as it fits, turn the engine slowly until it pushes the rope against the valves. The other way is to install a compression tester hose to the cylinder and pressurize it with shop air - you need to have a good compressor for that though. Zee