Don't use ether all the time, it'll only make matters worse.ELECTRICITY - Check:
-plenty of power (12V battery, 100AH minimal)?
-the 3 cables to and from the starter motor - are they secure? No broken wires or loose bolts? No parts that glow up when starting?
-any short-circuits (causing a loss of current)?
-the starter motor itself (take it to a pro unless you're familiar with electric motors) FUEL - Check:
-fuel tank clean? No rust inside? No rubble?
-fuel lines open, without any trapped air? Check this by loosening the small bolt on top of the fuel filter and working the manual fuel pump. Fuel should run out of the filter without air or dirt. Tighten the bolt, and repeat this procedure with the little bolt on the side of the injection pump.
-have the injector pump worked on if there's fuel leaking from the little pipe that runs down from the pump.
-have the injectors themselves checked and tuned. AIR - Check:
-if the airfilter is filled with clean oil
-if the mesh metal filter is clean
-if there's anything blocking the air supply MECHANICAL - Check:
-if the engine is properly 'timed' (meaning that the positions of the pistons, the crackshaft, the valves, the distribution network and the injection pump should be properly aligned; this is a common problem that can easily be solved)
-if the valves are properly tuned to specs
-if there's enough oil in the engine (of the correct grade).
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