This answer varies by vehicle type, so please be more specific.
At least 8
2
There are many gaskets on any car engine. If you are asking about head gaskets, they are between the cylinder head(s) and the engine block. The cylinder head is under the valve cover. --------------
There are many gaskets in many different vehicles. More info needed.
Silicone spray.
Yes.
yes, their sucking air, 65;
The year, engine size and if it is the intake manifold or an exhaust manifold gaskets would help.
you mean like on a car? Probably not a seal exactly. But i know you can get gasket material to make gaskets from many auto parts stores.
They have two.
There are a few gaskets on a car:- Cylinder Head, Water Pump, Inlet Manifold, Exhaust Manifold, Sump Cover,Thermostat Housing,Transmission Sump,Tappet Cover,Valley cover,Side Cover,Sump Plug,Differential Sump Plug, Transmission Sump Plug, Oil Filter, Oil Pump,Fuel Pump, I'm sure there are more but these will get you started Also door gaskets and window gaskets.
check your radiator hoses and change gaskets