It should be located on the left side of the engine (looking at the headlights), beside the exaust manifold.
In the engine bay
Replace the fuel filter.
NO, the Mazda B4000 is basically a re-badged Ford Ranger. The 4.0 L engine has a timing chain and not a belt.
4.0 l ford engine
To change the fuel filter on a 1999 Mazda B4000, first, relieve the fuel system pressure by removing the fuel pump fuse and starting the engine until it stalls. Once the pressure is relieved, locate the fuel filter, typically found along the frame rail. Disconnect the fuel lines from the filter, then remove the mounting bolts to take out the old filter. Install the new filter in the same orientation, reattach the fuel lines, and replace the fuse before starting the engine to check for leaks.
unhook the top radiator hose from the engine side of the hose, that's where you'll find the thermostat.
The thermostat may need to be replaced.
I believe it is on the drivers side of the engine , below the power steering pump
Checking on the location of the one for a 1998 4.0L: Under hood, center, upper engine area, mounted behind rear of intake manifold, in the engine block .
it depends on the bolt patterns but don't c y not but if its a 4x4tranny it may not if the Mazda isn't a 4x4
On the 4.0L 1994 B4000 it is located on the driver's side valve cover; towards the rear of the engine. Be aware that it may not have the plastic "L" on it so if you purchase a new one with the plastic "L", soak it in warm water for an hour to soften the plastic then pull the "L" off with a pair of pliers.
Iy is located on top of the large, black air intake tube- just after the air filter housing.