Injectors clogging

[Buckyjoe]

Been having problems with my 2004 Yamaha 4 stroke 115 hp for quite some time with fuel injectors clogging. Have cleaned them myself and replaced external fuel line and fuel water separator filter. Also cleaned vst filter Ran good for about 4 or 5 hours after doing this.
Experienced bad running again so pull injectors and send them off for cleaning and calibration. Put them back in and engine runs well for about 20 hours before same problem surfaces again.
Pull injectors clean them myself by forcing
injector cleaner through them backwards and forwards with 12 volt battery and air pressure. The spray looked good. Also used an external fuel tank with new fuel line and filter. Engine ran well for a few minutes before refusing to run at all.
At this point I am suspecting the fuel lines under the cowl may be deteriorating and particles are clogging the injectors. Any thoughts appreciated.

[rodbolt17]

has the VST been cleaned?
has the unit been updated with the filter between the lift pump and the VST?

[Buckyjoe]

Is there a new and better filter between lift pump and vst available? I have not replaced that particular filter. Do you mean by cleaning vst cleaning the inside of the reservoir and the filter? I have done that but am going to do it again and change the inline filter you were speaking of. Thanks for the info.

[rodbolt17]

that inline filter showed up on like the 05 or 06 production run.
wont show up on older parts diagrams.