Why air compressors in engine rooms?

Dewalt 20v leaf blower is a nice feature, too. Department of Redundancy Department.

Also useful for cleaning dryer vent lines.

Older boats use air shifting and throttle control. Some have air dampers that are air controlled. Others use air starters.

Here's one more use ... the air compressor in my engine room powers an air door on the aft deck. I love pressing the button and watching first timers on my boat jump back in astonishment as the door to the salon opens up automatically. It's the little things in life.

Oh Yes, Does it give the PSSTT that the doors in Star Trek did???

And getting bon fires going!

Why yes it did!

When I designed and installed my custom high volume, high pressure air compressor system I selected a volume behind my cockpit ice maker, using pressurized fresh air and a custom head manifold to supply massive system cooling for long term reliability, as-shown in this topic.

i remember that door on Johnson I ran for years. The compressor had a self purge feature that would cause a hissing noise every hour or two or so. Right next to the master.

Old, large diesel engines were started by compressed air rather than electric starter. When starting the engine, compressed air is admitted to whichever cylinder has a piston just over top dead center, forcing it downward. As the engine starts to turn, the air-start valve on the next cylinder in line opens to continue the rotation. After several rotations, fuel is injected into the cylinders, the engine starts running and the air is cut off.

The Stevens Duryea cars built in the 20's have the same air start system.

Thanks for the kind welcome. I am enjoying the forum so far

Many modern diesels still use air start but is typically done with a starter "motor" that uses compressed air vs batteries. To meet regulatory requirements there are large air receivers as you must be able to crank the engine and start it at least 5 times without a compressor refilling the receivers. This takes a lot of air. Because of the space required for the receivers, many are going away from air when they can. Lithium Ion batteries have made this possible where previously batteries were incapable of enough energy storage in a reasonable space and weight.