Feature 【Compatible】 Pressure Washer Soap Syringe Kit is compatible with pumps 190593GS, 190635GS and 203640GS. (1/8'' -27 BSP male thread) 【Replacement method】 Remove the old fuel injector with a wrench. Remove any sticky or dry soap from the container. Make sure the rubber o-ring is on the injector as shown. Put the ball bearing in the injector, and then use the spring on the small end of the spring against the ball bearing. Insert the injector into the socket and use a 13mm wrench to tighten the injector. Do not overtighten or it will damage the o-rings or crack the white metal on the pump. .