Logo

D2-55 Fuel Pump ?

tomcrowe

New member
I have a D2-55 w/about 150 hours on it that is not running well - it is a fuel problem, i'm not sure if it's the pump or the fuel filter system allowing air in somewhere. The symptom is that after 5-15 min of running at idle, the motor begins to sputter and then dies. After a weekend of troubleshooting here's where i'm at

a) watching the return line, it has a little return when running well, then slows to a drip then stops, then the motor dies.
b) using the hand priming pump on the motor - i can recover the stall if i'm quick enough. is it normal that the priming pump works stronger than the motor pump?
c) onboard motor filter, fuel pump internal filter and external Racor filters have been changed for new
d) all hose clamps and fittings have been checked for suction leaks
d) Lift from fuel tank level to top of system is about 4'
e) Running an aux electric pump used for polishing the fuel creates a good steady return stream and the motor will continue to run.

How much should be coming from the return line on this motor? it's only a trickle and less than i expected.
What's the max lift for this motor (before filter restrictions)?
I have Racor500 filter units and the lid attachment (o-ring at t-handle) gives me less than confident feeling of a good seal - any thoughts or experience with these?
I have Groco tank select and filter select valves - again the stem seal o-ring gives me less than confident feeling of a good seal - any thoughts or experience with these?
Other thoughts on the diagnosis?

Thanks,
Tom
 
Pumping primer bulb is a substitute for a weak fuel pump. Pressure test pump output. Everything is pointing towards a weak pump!!
 
Hi have had the d1 and d2 lift pumps get and bit of air in the if the out let of the pump is pointing down.
There is enough room to turn the pump around.
 
Hi have had the d1 and d2 lift pumps get and bit of air in the if the out let of the pump is pointing down.
There is enough room to turn the pump around.

Good suggestion about the pump - I've turned the pump - a bit worried about the bend in the hose causing constriction, but will see how it goes.

as an update -
i've changed the pump - no change (so now i have a spare :)
I've changed the priming button assembly - no change (so now i have a spare :)

I've concluded and am in the process of changing
a) my filter/valve assembly to be lower (at least 5' from the bottom of the keel tank right now - i can probably lower to 3') this will also make the engine priming pump air bleed valve the highest or close to highest point in the system, making bleeding easier.

b)out the many clamped hose to hose barb fittings with threaded compression type fittings - will make disassembly easier in the future, but most importantly, will more reliably seal any air leaks i may have in the system.

Updates soon
 
Back
Top