Fuel pump attachment

I fabricated the plate to mount the EFII fuel pumps on based on the length of the support angles underneath, and then attached the pump to the hose - aaand the plate was too short, probably because with the wing-root-filter variation of the Aircraft Specialty hoses, the pump gets shifted slightly forward:

Fuel pumps on the initial support plate (too short)

so I made a new plate, this time about 1 1/4" longer on the forward end (and sent it to Aircraft Specialty - they even included it in a newer revision of their manual!):

Drawing of the fuel pump support plate with dimensions

With that, the pumps and hoses fit perfectly, so I used the template included with the pumps to drill holes for those, and made smaller holes for #8 screws that attach the plate to the angles underneath, then match-drilled those:

Fuel pumps attached to hoses, with the longer support plate

Fuel pumps on the support plate

Pump support plate and angles

After primer, I installed the nutplates, angles and the pumps themselves (those use a 1/4-20 bolt, so not AN4s). Installing the angles made me realize that the MSP-42 rivet that the Aircraft Specialty recommends is fine on the side without the inspection panel, but with the added thickness of that, MSP-43s had to be used on the right side:

Primed pump support plate and angles, with nutplates riveted

Pump final-attached to the support plate

Support angles riveted in place

With this, only the final assembly of the pumps/forward hose are left for this section (and pump wiring which I'll count towards the avionics section) - I'll do those once I'm ready to close the tunnel.

Time lapse:

Total fuel system rivets: 30
Total fuel system time: 12h

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