When I changed the fuel filter on my B7200 I found a needle valve on the injector pump. The B1700 I believe is very similar so you may want to check that out for cleaning. The needle valve is located on the end of the fuel line coming from the fuel pump and has a thumb screw on the top, parts diagram #010 on page 12. If you don't already have a parts diagram book you will find one, free at "www.kubotabooks.com" . Good luck and don't forget to bleed the 3 inject lines right on top of the engine. The books don't tell you to do that.