If it pulls a vacuum, the lift pump is fine. You have an obstruction in the tank, hose, or inlet to the water separator.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.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?
Over my 9 years here on OTT, several folks have found some crud plugging up the inlet to the separator, just like Jim did.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 guess I'm going to have to take the tank off and clean it. I was hoping to avoid that labor intensive task.If it pulls a vacuum, the lift pump is fine. You have an obstruction in the tank, hose, or inlet to the water separator.
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.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 the cap vent and tried running it with the cap removed completely. I will definitely check the WS assembly for any obstructions.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.