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Alright so ive got a 95 CTD in a 94 F350. I started running biodiesel in my truck about a month ago when I finished my conversion. Right after I filled it up the very first time (i mean with in a mile) the truck started sputtering and stalled. It feels like I am running out of gas, I have been filling it up with regular #2 and it seems to be better but the motor will still bog down and it feels like im not getting any fuel. It only stall every now and again but i just cant figure it out. Ive changed all the filters several times and I dont know whats next.....thanks fellas
 

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Biodiesel has more "solvency" than dino. May have just opened up an air leak. You can use a rag around an air hose in the tank filler neck to create a few pounds of positive air pressure and see if you can find a wet spot in the supply line somewhere to confirm or eliminate this possibility.

Might also try a double dose of injector cleaner and drive it like you stole it for an hour or so and see if it will clean up.

The 12v engine should run like a champ on biodiesel.
 

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Bio is a fairly strong solvent. It will loosen all the dino gunk in the tank and promptly plug up your fuel filter. Course you already know that, I wonder if the pickup screen in the tank is plugged with dino gunk? SLICK CONVERSION congratulations. If the in tank screen was gunked up, you could probably find out by teeing into the suction side of the lift pump and checking for vacuum. Should have virtually none.

You did change the fuel filter at least once AFTER the bio right?
 

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Discussion Starter · #4 ·
Biodiesel has more "solvency" than dino. May have just opened up an air leak. You can use a rag around an air hose in the tank filler neck to create a few pounds of positive air pressure and see if you can find a wet spot in the supply line somewhere to confirm or eliminate this possibility.

Might also try a double dose of injector cleaner and drive it like you stole it for an hour or so and see if it will clean up.

The 12v engine should run like a champ on biodiesel.

I actually just had the injector cleaned and pop tested and they were all A -ok. Im still going to try the injector cleaner just in case. The leak I havent looked for I will check it out.

My truck only does it randomly though. Not all the time.

Bio is a fairly strong solvent. It will loosen all the dino gunk in the tank and promptly plug up your fuel filter. Course you already know that, I wonder if the pickup screen in the tank is plugged with dino gunk? SLICK CONVERSION congratulations. If the in tank screen was gunked up, you could probably find out by teeing into the suction side of the lift pump and checking for vacuum. Should have virtually none.

You did change the fuel filter at least once AFTER the bio right?
My truck was a gasser for 99% of its life, I have changed the fuel filters twice on 1 tank of bio. Im thinking it might be the pickup tube from the sending unit. Im gonna drop the tank this weekend and tear it apart and see what i come up with.

o and thanks
 

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EEK! Definitely look for seals and stuff in the fuel system! A whole lot of gasoline stuff will puff up with biodiesel. I even had an auto shut off nozzle get ruined by it (filling station style nozzle). Some of the plastics/rubbers may not be up to the task. Diesel fuel plumbing is usually bio safe in relatively new vehicles, but with a gasser conversion, it very likely will NOT have bio safe materials engineering.

That conversion sound even SLICKER since you sent a gas engine to the scrapheap! :)

PS another thing to consider is that perhaps a fuel line puffed up and the lining is seperated and plugging things up. Personally I would replace all the fuel lines anyhow if you haven't already. Especially since it was a gas truck.
 

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Checking the tank strainer and changing the rubber fuel lines both sounded reasonable.

You said you changed the fuel filter but you did not mention cleaning the strainer in the strainer/heater before the mechanical lift pump (This is also a notorious place for an air leak). A fuel pressure gauge might tell you something.

Have you done an autopsy on any of the filters you changed to see if they were gunked?
 

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Discussion Starter · #8 ·
Checking the tank strainer and changing the rubber fuel lines both sounded reasonable.

You said you changed the fuel filter but you did not mention cleaning the strainer in the strainer/heater before the mechanical lift pump (This is also a notorious place for an air leak). A fuel pressure gauge might tell you something.

Have you done an autopsy on any of the filters you changed to see if they were gunked?

I was thinking about dropping the tank this weekend and checking the screen in the gas tank.

I did do an autopsy on the fuel filter also, it was kind of interesting. It was dirty but not as bad as I thought it would be.
 

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If you change the "rubber" lines, be sure that you get lines equivalent to OEM. The normal gas hose you get at the parts house isn't good enough. You need the hose with viton lining that is designated for fuel injection.
 
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