Diesel lift pump; worked then didn't

[WayneBurton]

John Deere 2002 Diesel Gator 6x4 18 HPO Yanmar
Have Gator Service manual; not very helpful on this topic
Problem
Changed fuel filter, ran good for 5 minutes then died.
Getting gravity flow of fuel thru filter at pump, manual pump handle or cranking will not flow fuel on outlet side. Manual handle has dead feeling, not pumping anything
ODD?
Two questions.
1. Is this fuel lift pump a gear driven or diaphram type?
General appearance suggest cam driven diaphram type.

2. Is there a secret to bleeding a diesel gator, for example, remove vent line at tank and pressurize, remove return line at tank and vacuum, etc?

Thanks ahead.

Wayne

 

[milkman]

Drain tank, put in another new filter and clean diesel, water will saturate the filter and stop fuel in a short order.

 

[WayneBurton]

Milkman,
Determined that I need a new lift pump. Pick up today.
The two questions I asked were: Is the lift pump diaphram or gear driven style? AND is there a simple way to bleed the system?
I removed the inlet hose (at pump) and inserted my own hose into fuel. The pump will neither hand pump or crank pump. The manual indicates it only pumps 4.3PSI and not a lot of volume; hince my design and bleeding tip question.
There is no water in my diesel. I looked at filter again. Fuel is clean. My problem is lift pump not pumping. My questions were on pump design and bleeding tips.

Drain tank, put in another new filter and clean diesel, water will saturate the filter and stop fuel in a short order.

QUOTE: Wayne Burton: "Getting gravity flow of fuel thru filter at pump, manual pump handle or cranking will not flow fuel on outlet side. Manual handle has dead feeling, not pumping anything"

 

[milkman]

Sorry disregard first post

1. don't know

2. no

 

[WayneBurton]

Problem fixed shortly after postings. Lift pump was bad. Strainer on pickup needed cleaning, but was not the problem.

One method on Diesel 6x4 to quicken the bleeding process:

1. Open fuel from tank (L) at lift pump and get fuel flow. Tighten. (14mm BE WR)
2. Remove one of the pass-thru return lines on top of the filter, and make suction until fuel is present or near present. This will shorten cranking significantly. (As book indicates, the system is self bleeding, but not instantly bled. Cranking to bleed only is like a thousand starts to the starter.)
3. Using 17 OE mm, loosen injector lines and crank in 10 second bursts and rests until air is purge. Tighten injector lines.

Geting fuel to pump, thru filters thru return lines to pass thru at filter will spare excessive cranking and pre-mature starter failures.

Wayne