Re: Fuel pump and filter mystery

It's a Yamaha 2QM20. The bottom of the tank is above the engine fuel pump but the fuel line was run to about level with the top of the engine. The primary Racor 200 (discontinued) used to be fairly high but I moved it down to the bottom front of the engine bed where it is easy to inspect and replace. The electric pump has always been there but I'm going to look carefully at the system this winter and see if I can eliminate it by rerouting the fuel lines. I would still keep an electric pump for bleeding and in case the diaphram on the engine driven pump fails.

The secondary filter is at the top of the engine. I'm running 2 micron elements in both filters. I think the fuel system is pretty clean because there was not so much as a speck in the fuel I drained out of the sediment bowl or the bowl for the secondary. I've used nearly 200 gallons of fuel this season and bounced around a lot.

A vacuum gauge for the primary is on the list of improvements this winter but the problem this time seems to have been the secondary. It is downstream of both pumps so I can't put a gauge on it.

I'm not entirely sure that either filter was clogged. The process of replacing the secondary and bleeding the system could have dislodged something else.

--
Roger Long


.

Relevant Pages

  • Re: EP: Yanmar YSB12 starts after long layup,..
    ... the engine with the hand crank periodically over a few days it came ... The Oil Strainer: ... using a 12v electric pump with a hose attached ... After opening the tank gate it took ages for fuel to fill the CAV ...
    (rec.boats.building)
  • Re: Replacing Injection pump-Engine block gasket
    ... I got around to replacing the gasket between the injection pump and the motor block. ... Below the hand pump - the fuel inlet from the tank via the small transparent filter. ... This one is the fuel return line that starts on the engine side of the injection pump, goes to the top of the main fuel filter and then attaches to the return line that goes back to the tank. ...
    (alt.auto.mercedes)
  • Re: Stalls on decelleration and when nose is down
    ... Someone who knows a lot more about these things than I ever will e-mailed me to point out that there is enough fuel in the carb bowl to let the engine run for a minute or so. ... I am wanting to get the fuel pressure up to the specified 3 to 5 psi range. ... Braking and nose-down conditions pull fuel toward the front of the bus, away from the pump and I guess the pump does not have sufficient sucking power to keep it, er, up. ...
    (rec.autos.makers.vw.aircooled)
  • Re: Fuel System Musings, comments encouraged
    ... the VW fuel pump is driven at cam speed but it ... spring rather than by the engine. ... the push-rod slightly more than that. ...
    (rec.aviation.homebuilt)
  • Re: 1.8 Escort Diesel problem - no fuel at injectors
    ... Escort diesel van, 1.8 normally aspirated engine. ... Changed the fuel filter after work, ... not a sign of fuel leaving the pump. ... way I was bypassing the immobiliser side of things. ...
    (uk.rec.cars.maintenance)