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Discussion Starter #1
I have been running B100 Bio Diesel for a month now. I have changed the fuel filter a couple of times (every 500 miles) as the old diesel residue clogs them.

Today I noticed hesitation when I used throttle, and went very easy on the way home. I limped back at low speed experiencing some surging; I have experienced this before with dirty filters, and when I changed them it has always fixed the issue.

I did my oil/filter change, fuel filter change, and external transmission filter change. I was unable to prime the fuel system, checked O-Rings and bleed screw, as well as re-seating the new fuel filter?

I have pumped and pumped to no avail? Any help would be greatly appreciated.

R/

Doc
 

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Discussion Starter #2
I tried again this morning, but all I hear is air sucking. Maybe I'll try it with the fuel tank cap off this evening.

Hopefully the fuel lines are not clogged?

Does anyone know if the truck has to be level for the priming pump to work?
 

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I have primed mine on an incline. Your primer pump may be bad. I have heard where some guys have taken their fuel cap and put a valve stem or air chuck adaptor and then pressurized the fuel tank and then crack the bleeder screw open a little to get the air out of the system. I am assuming that after installing the filter, you didn't try and start the truck? I normally put the new filter on and then start the truck, let it die, and then bleed the air out the of system.
 

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Discussion Starter #4
I usually do not start the truck before priming the new filter; if having this much air in the line is the result, I will definitely start.

I am about to try pressurizing the fuel tank as you suggested.

Thanks for the input, I am getting tired of driving the Toyota.
 

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Discussion Starter #5
Okay, I was able to get fuel out of the bleed screw when I pressurize the fuel tank (used a Powerade bottle with a blow gun/pancake compressor).

I still cannot get a steady stream of fuel out of the bleed screw with the priming pump. The pump does not really feel broken, but it should be able to pull fuel?

The engine ran a few seconds after pressurizing the tank, then died? I am waiting for my wife to come home so she can try to start it while I pressurize the tank; I am hoping to prime it this way?
 

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is it leaking anywhere when you pressurized the tank? could the old gasket possibly get stuck to the housing and not come off with the filter? now you may have 2 gaskets in there. could you have cracked the plastic water sensing unit on the bottom of the filter? leaks while under pressure would point out these possible problem areas for you. I'm using my own b-20.
 

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Discussion Starter #7
I got it running by pressurizing to prime, then getting my wife to start it under pressure.

Both O-Rings came out with the old filter; and I inspected/cleaned all components before pressurizing the tank.

Either I had a huge amount of air in the lines, or my priming pump is shot. I have not checked the priming pump since I got it running.

Thanks for all the help fellas!
 

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Discussion Starter #8
Just checked my priming pump after installing new filter; it's shot:tease Anyone know where I can get the rubber and soft spring that goes inside? I'd rather not buy a new pump/filter head.

Thanks in advance.
 

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