Kenworth, 18 Litre CAT V8, Cold Start!

Sitting for a few weeks, cold start with some smoke!

Advantages of air start:
They have a longer working life than electric.
No need to worry about flat batteries, every tyre on the truck is basically a battery, because if you run out of air you connect your airline to a tyre to charge the starter air tank.
The starter air tank is seperate from the main air system and will hold air for weeks as long as everything is well maintained.
They spin the engine over a lot faster than electric.
Alternators and batteries last a lot longer because they don't have the heavy drain of electric starts.
The system is lighter than an electric start system.
You can run your fridge without worrying if the batteries will go flat.
Disadvantages:
You must maintain the system or you will run out of air.
They are a lot more expensive than electric start systems.
You must make sure they are lubricated, this is the #1 reason people have problems.