FMTV fuel system questions

[Reworked LMTV]

I have never dealt with diesel truck engine fuel delivery, always gas. Thus, I don't know that much about the delivery system differences, other than the mega expensive, don't touch it, injector pump lol

My question is this. A common "dead on the side of the road" issue in gas vehicles is a dead electric fuel pump. Can I assume the same theory FMTVs? I have not seen a reference to a pump in the tank in the TMs. Is that right? Maybe this is a CAT part?

 

[Coffey1]

 

[Reworked LMTV]

Anyone had one of these mechanical pumps fail?

 

[Reworked LMTV]

https://www.justanswer.com/heavy-eq...eplacing-mechanical-fuel-pump-electronic.html

Interesting discussion here.

 

[snowtrac nome]

I have a buddy at the local cat dealer truck engines is all he does, I asked about an electronic lift pump and his answer was the positive displacement pump in the 3116 will last a lifetime as long as you don't get air in the system say from a leaky filter housing. it will flow enough fuel to support more hp than the 3116 can survive. the only thing he suggested was if you don't have a check valve in line it may be a good idea to add one. the lift pump works the same as a Detroit lift pump which I have seen a few fail in my life time bit look how many 2 cycle Detroit's have been built through the years.

 

[scottmandu]

I have never dealt with diesel truck engine fuel delivery, always gas. Thus, I don't know that much about the delivery system differences, other than the mega expensive, don't touch it, injector pump lol

My question is this. A common "dead on the side of the road" issue in gas vehicles is a dead electric fuel pump. Can I assume the same theory FMTVs? I have not seen a reference to a pump in the tank in the TMs. Is that right? Maybe this is a CAT part?

Check your fuel lines. If they haven't been replaced it's probably a good preventative measure.

 

[Reworked LMTV]

Check your fuel lines. If they haven't been replaced it's probably a good preventative measure.

Sounds good to me.

 

[Aernan]

Fuel filters won't flow of they get water and algea in them. First step should be to swap both filters.

My cat mechanic says the first filter is low pressure the second high pressure. I have no idea how to safely depressurize the system.

In a diesel system fuel deposits and carbon can build up. You can get fuel additives. The other option is running biodiesel. In California b20 (20% biodiesel) is common. I believe you can also run b100.

The other thing to keep in mind is deposits will build quickly if the engine doesn't come to full temp before shutdown.

Sent from my SAMSUNG-SM-G930A using Tapatalk

 

[coachgeo]

There are Three good thing about adding an Aux. Diesel electric Fuel pump BETWEEN the engines Lift/Suction Pump and tanks. Engine lift pump SUCKS fuel up the fuel line from the tank all the way up by the engine. Benefits of Aux. pump is one- easy priming from Aux. pump up the engine lift pump. Might push on thru and help prime further as well. Two- too assist if you get an air leak between lift pump and Aux pump and you want to limp on to another location before stopping to deal with it. Use it mainly for those two purposes. Third it MIGHT help you find an air leak. Not always..... but sometimes the leak is big enough the Aux. fuel pump will push Diesel out the hole. loose fitting etc. But not always. Suction from lift pump can pull up a flap of fuel line peeling off inside and let air in........ while positive pressure from an Aux. fuel pump will potentially actually push it closed.

Best place to install an Aux. pump is as close to the fuel tank as you can get it. Put a switch for it on the dash.

PS- have not looked close to see if the CAT has a lift pump or a tank pump like more and more diesels do these days. From above info it sounds like it does have a Lift pump.