New Holland LX885 fuel issues

[TVA]

TVA - a stupid question. Where is the lift pump? It does not have the electric pump as shown in the parts manual and does not show anything on the hydraulic lift pump. Any ideas?

I think there’s none. Just that hand pump, and everything else is done by injection pumps “transfer pump”.
Thats what makes it not that reliable.
You can look at your engine sides, they usually run off of the cam on the camshaft.
I remember looking at the parts daiagram for those NH engines, and all I saw was that hand pump, in my case they were eliminated on all 3 of the forklifts long before I started working on them.
But in my case it’s little better, because the tank is higher than the injection pump, and it does have gravity feed.

What i see from pictures you send - your tank is below the injection pump.
You can follow the hose from the tank, and see if it will take you to the lift pump, if there is one.

 

[TVA]

TVA - Do you know if the fuel tubes in the tank give problems? My brother has a JD and a Bobcat and both have had broken fuel tubes in the tank.

Yes it can happen. In that case you’ll be fine with full tank, but start having problems when level is dropping

 

[TVA]

I think this is your hand pump, mushroom looking one, in front of the filter housing. That’s a “second” generation of fuel systems on those. Last one is newer single lock-ring style filter element.

 

[TVA]

Previous system had the hand pump on your diagram, it was mounted on the back of the engine, ritht where engine mates with bell housing

 

[TVA]

If you have electric one, it’s mounted in your tank, but is separate location from your fuel level sender. Because I don’t see it with the sender in your picture

 

[TVA]

Parts diagram what I can find do not show a lift pump. Fuel comes off from the top of the tank, to the left from sender unit ( not visible on your picture) and goes straight to the fuel filter housing

 

[TVA]

 

[TVA]

Pickup tube 6, clamps 7 and hose 8

 

[houser]

I think this is your hand pump, mushroom looking one, in front of the filter housing. That’s a “second” generation of fuel systems on those. Last one is newer single lock-ring style filter element.

TVA - thanks, yes, I have the hand pump to prime it. On my diesel truck, I have a "lift pump" that ensures fuel is fed to the injector pump. On my truick, If the lift pump fails, the injector pump fails because the injector pump used the diesel as a lubricant to keep it oiled up. WIthout a lift pump, how does this thng maintain "prime"? It has never had a problem until now with any fuel-related issue.

 

[houser]

Pickup tube 6, clamps 7 and hose 8

TVA - yes, that is the system I have. Thanks,

 

[TVA]

TVA - thanks, yes, I have the hand pump to prime it. On my diesel truck, I have a "lift pump" that ensures fuel is fed to the injector pump. On my truick, If the lift pump fails, the injector pump fails because the injector pump used the diesel as a lubricant to keep it oiled up. WIthout a lift pump, how does this thng maintain "prime"? It has never had a problem until now with any fuel-related issue.

You must have Dodge Cummins with VP44. When lift pump doesn’t produce much fuel, the computer in the head of the injection pump overheats, and also over time steel diaphragm inside the injection pump may crack.

This one has a small vane pump, Lucas/Delphi call it “transfer pump”, it sucks the fuel in, and uses internal “transfer pressure” to spread high pressure plungers apart before cam ring will push them together to produce that injection stroke.

That’s why this set up is not that reliable - everything is suction before that strainer I told you about, besides when you using hand pump.
And if something sucking air - it will not show up as a fuel leak at that place, unless you pressure rise it with remote pump all the way from the tank or remote reservoir. And that’s why it is sensitive to any little bit of restriction.

 

[TVA]

I circled the parts of the transfer pump, and transfer pressure regulator, 30 is that strainer I told you about.

 

[TVA]

39 through 44 is a pump itself

 

[TVA]

Another word of caution, those fittings in all of those steel lines use rubber grommets in them, when grommets get chewed up or get hard ( over time from engine heat, it gets worse in freezing temperatures) - they also start sucking air.
That system is a lot of “fun” to deal with.
It’s frustrating as heck!

 

[houser]

Another word of caution, those fittings in all of those steel lines use rubber grommets in them, when grommets get chewed up or get hard ( over time from engine heat, it gets worse in freezing temperatures) - they also start sucking air.
That system is a lot of “fun” to deal with.
It’s frustrating as heck!

TVA - Thanks again! You've been a great help! Going to work on it now.

 

[TVA]

Good luck.

 

[houser]

I think this is your hand pump, mushroom looking one, in front of the filter housing. That’s a “second” generation of fuel systems on those. Last one is newer single lock-ring style filter element.

I replaced the fuel filter and cleaned the sediment bowl out. Now I cannot get fuel to pump up through the system using the hand pump to prime it. Any ideas on this issue?

 

[houser]

U see the double screw next to the name plate on the side of the inj pump, 7/16 body with a 5/16 screwed into it..
THATS the bleeder screw.. loosen the 5/16 and crank the engine.. it should shoot fuel a foot or 2.. with NO AIR.. snug it back up..

By the looks of the filters, they haven’t been changed in a LONG TIME..
U might wanna put THAT on ur to-do list..

thepumpguyssc - I replaced the fuel filter and cleaned the sediment bowl. I first tested as you suggested, the 5/16 screw - no to very little fuel came out. I then tried cracking the injector lines open and the same thing, no fuel. I took the hose off the tank, placed one that I could blow through and heard bubbles from inside the tank. I replaced the fuel line. Now, I cannot get the primer pump to pull fuel up and fill up the sediment bowl and fuel filter. I guess I can try the air in the tank and push fuel up to the filter and sediment bowl. I'll post pics a little later.

 

[thepumpguysc]

If u can’t get fuel out of that double bleeder screw, ur not gonna get fuel out of the lines AT THE INJECTORS..
Definitely try pressurizing the tank to get the fuel to the inj pump..
Don’t blow anything up.!!
U can over pressurize the fuel tank AND the filters..
Good luck

 

[houser]