CAT 420 Fuel system issues (Gas in fuel tank)

[ElPelaVacas]

Good morning,
I'm in an interesting situation with a 420 backhoe, a few days ago this machine arrived and one of the yard guys said it ran 'funny'. I went to go drive it and found a number of issues with it. For one, the serpentine belt had ripped and was laying on the ground next to the machine, it was also throwing emissions codes 157-12,3714-31,3719- 0, and 3719-16. That's not all though, when i did manage to replace the belt and turn on the machine, the machine ran terribly and sounded like it was starving for fuel, i went to go check the fuel tank and noticed it smelled off. Took a sample and im about 90% sure its diesel mixed with gasoline. I drained the tank and fuel filter and ran the machine hoping that it would magically fix it but it did not. It still runs terribly and almost shuts off when raising the rpms. Has anybody ever dealt with something similar? Is it going to need a new fuel system? Let me know!

 

[Nige]

First up - machine Serial Nnumber please.

You said that you "drained the tank and fuel filter". Have you actually changed any fuel filters yet.?

Out of that list of Codes you posted above, which ones are Active.?

 

[ElPelaVacas]

SN-0H8T01190
I drained the fuel tank and replaced the fuel/water separator filter. The 157-12 is an active diagnostic code while the other 3 are active event codes

 

[Nige]

157-12 is related to the fuel rail pressure sensor.

The other three are actually DTCs and are all related to the DPF soot loading. See attached.

 

[Island_catguy]

With the key on, can you hear the electric feed pump hum? Also are you having any white smoke? How does it sound at idle?

You can pull off the bottom pipe of the muffler before the dpf, or the clamp at the turbo. So we can see if the muffler is so blocked it is causing the machine to almost die when actuated.

If you have access to cat et, we can look into a lot more helpful troubleshooting.

You changed the fuel water seperator, did you also change the fuel filter (also an element style filter).

When the belt snapped, did you make sure the alternator or compressor isn’t seizing?

It’s best to troubleshoot the fuel system first as it can throw all the emission codes from misfires, wrong fuel, etc.

 

[thepumpguysc]

I haven’t checked to see if it actually happens, but it might be possible for the gasoline traveling thru the system to swell the rubber “olives” that seal the lines..??
Just throwing it out there..
Good luck

 

[Simon C]

I fixed a guys ford Powerstroke 7.3 liter that was wild smoking and turned out to be tank full of gas. The injectors were junk and we had to flush the system a couple times.
If the gas hit the injectors, they will show it.
Simon C

 

[Coaldust]

Is your fuel supplier wet hosing your equipment?