Yes
Harness was submerged, It needs to be thoroughly cleaned. I would remove the harness and fill a container with white vinegar and let it soak. Then pull out and soak in clean water. Then spray down with WD40 and then air hose and blow dry
Anyone install a retractable sun shade? Doesn't need to be "Sun Shade" just have a link for others to get idea
https://www.sureshade.com/
The new boat has a hard top and looking into a rear sun shade/screen
Could install a fuel pressure/vacuum gauge on one of the filters. If first filter before the supply pump then vacuum gauge, and if after the pump then pressure gauge
Most likely your good, it revs up and such
Maybe someone replaced it and did it incorrectly
The one in pic has power direct to float as Bondo mentioned. Also has power from the fuse box to a switch for direct power ON. The light will light anytime power is applied to pump. Note there are 2 fuses (inline direct from Bat and one from box)
Could get it clean with wire wheel or other things. Wash down with acetone and use JB Weld or other epoxy. Best to just replace but understand maybe not now
The seal looks good, looks like its just barely below the ring surface. The spacer is for the most part a washer (flat bushing) to keep the ring spaced from the lower housing
Shifting to design 3 housing should be straight forward without using the Y-pipe supplied. It might be needed if the old Stat is being used but I would switch
Never liked prefilling a diesel filter, gas is ok but not diesel. The diesel injector nozzle are just really small and one spec can clog it. The manual posted previous it list the motor can have 2 filters not counting the screen filter on the fuel pump. It says to loosen the bleed screw and...
The link is a pdf manual. Look on starting on page 17 it tells how and where the hand primer is. Note it the fuel can not be pumped it says to bump the starter to move the cam on the pump
http://www.varen4u.nl/pdfs/volvo/Volvo_MD5A_manual.pdf
