Running anything but Motorcraft Beru ZD9 glow plugs is taking a big risk of failure. A tip breaking off can ruin an engine. At the very least it ruins a piston. If you have a turbo it will destroy the hot side wheel. So now how expensive does a set of Berus look. If you don't have the money to pay for Berus you can disable the glow plug controller and use ether to start the engine without any issues but you need to nkow how to use it. A less than 1 second burst is all thats needed into the intake path. Then crank for about 5 seconds. Do it again if its not starting. Never wet the intake with ether. Ether done correctly is harmless. done wrong its crack in a can and will kill an engine.