Yanmar 155D fuel system

[SteveinMescal]

I recently bought a 80 Yanmar 155D.
Runs great (low 130hrs!) at one point someone added a in-line 12-volt fuel pump (wired to the keys switch)
They also removed the stock fuel filter assembly entirely.
(There is a small inline filter screwed into the inlet side of the electric pump)
My first thought is to remove the electric pump, get the fuel filter assembly from Hoye Tractor and return the system to it's original configuration.
Any thought as to why someone would have done this in the first place?
The diagrams show it originally being a gravity fed.
Only thing I can think of is someone didn't bleed the system properly and had a no-start issue maybe.

 

[California]

Same experience when I bought my YM240 in 2003. A small lawnmower-type filter in place of the original. I first got a "for-Yanmar" filter assembly from a mailorder tractor parts house. It was worthless because it had an extra fitting intended for a hose with clamp, that I couldn't seal. Don't make that mistake!

I then got the authentic parts from an importer, who had a lot of broken warranty return tractors parked out back.

Hoye should have that authentic assembly, used, and I recommend this, but expect to pay for it.