Still starving for fuel

Kbtaman65

New member

Equipment
M5040
May 20, 2022
26
10
3
Marion NC
I've syphoned the fuel out and refilled it. I've changed the fuel filter. My M5040 is still pulling a vacuum at the water separator. Could this be a lift pump problem?
 

whitetiger

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Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
Nov 20, 2011
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Kansas City, KS
I've syphoned the fuel out and refilled it. I've changed the fuel filter. My M5040 is still pulling a vacuum at the water separator. Could this be a lift pump problem?
If it pulls a vacuum, the lift pump is fine. You have an obstruction in the tank, hose, or inlet to the water separator.
 
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Tx Jim

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M7040 HDC-1,JD 4255,Ford 6700
Apr 30, 2013
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Coyote Flats,Texas
Welcome to OTT
Yrs ago I owned a M4900 that acted similar pulling vacuum in WS bowl. I located a clogged fuel passageway in water separator housing. Also check to be sure fuel tank is venting so not to create vacuum in tank as fuel is exiting.
 
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19thSF

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B2650, loader, MMM, pallet forks, tooth bar, rear blade, JD 318 w/plow, JD X350
Mar 1, 2020
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Glendale, Rhode Island
I've syphoned the fuel out and refilled it. I've changed the fuel filter. My M5040 is still pulling a vacuum at the water separator. Could this be a lift pump problem?
Here is a long shot, but an easy "try it". Check the breathers in the fuel cap. If clogged, no air in, no fuel out. Try starting and running with the cap off, or loose.
 
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RCW

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BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
Apr 28, 2013
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Chenango County, NY
Welcome to OTT
Yrs ago I owned a M4900 that acted similar pulling vacuum in WS bowl. I located a clogged fuel passageway in water separator housing. Also check to be sure fuel tank is venting so not to create vacuum in tank as fuel is exiting.
Over my 9 years here on OTT, several folks have found some crud plugging up the inlet to the separator, just like Jim did.
 
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Kbtaman65

New member

Equipment
M5040
May 20, 2022
26
10
3
Marion NC
Here is a long shot, but an easy "try it". Check the breathers in the fuel cap. If clogged, no air in, no fuel out. Try starting and running with the cap off, or loose.
Thank you, I had actually thought of that and tried running it with the cap completely off. It must be something in the fuel tank.
 

Kbtaman65

New member

Equipment
M5040
May 20, 2022
26
10
3
Marion NC
Welcome to OTT
Yrs ago I owned a M4900 that acted similar pulling vacuum in WS bowl. I located a clogged fuel passageway in water separator housing. Also check to be sure fuel tank is venting so not to create vacuum in tank as fuel is exiting.
Thank you, I had actually thought of the cap vent and tried running it with the cap removed completely. I will definitely check the WS assembly for any obstructions.
 
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