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No, it is bad for the injection pump's head and rotor due to the lack of lubrication that the fuel normally provides.
 

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And now there is air in the system, start priming...
 

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Discussion Starter · #4 ·
my son works at a oil changing place and he says they prime the fuel filters with tranny fluid...
 

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Discussion Starter · #5 ·
No, it is bad for the injection pump's head and rotor due to the lack of lubrication that the fuel normally provides.
if it is just for the little bit that you try to start it is it going to hurt the pump?
 

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As sdstriper said you need to fill the filter and prime the injection pump. When you spin the engine with a dry injection pump you shorten the life expectancy of the pump.
 

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Running a 24-valve electronic pumped 6BT is not a good thing. You can easily wreck the electric (POS) OEM lift pump. The P7100 and Rotary pumped 12 valve motors are a little more forgiving. On a 12 valve motor, there is a hand priming pump on the lift pump under the fuel filter to prime with. You will need to push it about 10,345 times to get fuel to the filter and another 347,887 times to fill and bleed it. I hope you have a strong finger.

Priming with ATF will work, but will coke up injectors very quickly. Diesel is much cheaper, too.

Take care and watch the fuel gage. It's there for a reason. :rasta:
 

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Discussion Starter · #8 ·
thanks for the info...i think they got it started.i think they use the ATF becuase the dont have fuel there
 

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On a 12 valve motor, there is a hand priming pump on the lift pump under the fuel filter to prime with. You will need to push it about 10,345 times to get fuel to the filter and another 347,887 times to fill and bleed it. I hope you have a strong finger. :rasta:
I now know he's not kidding

Gaza
 

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Running a 24-valve electronic pumped 6BT is not a good thing. You can easily wreck the electric (POS) OEM lift pump. The P7100 and Rotary pumped 12 valve motors are a little more forgiving. On a 12 valve motor, there is a hand priming pump on the lift pump under the fuel filter to prime with. You will need to push it about 10,345 times to get fuel to the filter and another 347,887 times to fill and bleed it. I hope you have a strong finger.

Priming with ATF will work, but will coke up injectors very quickly. Diesel is much cheaper, too.

Take care and watch the fuel gage. It's there for a reason. :rasta:
if you're having trouble priming a 12v, bump the starter. if the lift pump isn't on the base circle of the cam lobe, it'll take forever to prime. I've never encountered an issue priming one. the 97-98 trucks are way easier due to lack of vac booster on the firewall. you can use a broomstick
 

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Running a 24-valve electronic pumped 6BT is not a good thing. You can easily wreck the electric (POS) OEM lift pump. The P7100 and Rotary pumped 12 valve motors are a little more forgiving. On a 12 valve motor, there is a hand priming pump on the lift pump under the fuel filter to prime with. You will need to push it about 10,345 times to get fuel to the filter and another 347,887 times to fill and bleed it. I hope you have a strong finger.

Priming with ATF will work, but will coke up injectors very quickly. Diesel is much cheaper, too.

Take care and watch the fuel gage. It's there for a reason. :rasta:

I managed to prime mine at 347,886 times:hillbilly:
 

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we prime 80 trucks a day,was over a 120 and unfortunately that was my job during the difficult years of pressurizing the tank and cracking fuel injector lines.I meant to post this many months ago when I joined .Go to cummins and buy a priming port[2 pieces ]remove the plug at filter and install.purchase a boat motor oil removal pump $30 and it will pull fuel from the tankto the filter.this system works very well and it no longer takes a mech to start trucks at work.
 

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I've heard of people stuffing a hose sealed w/ a rag into the fuel filler neck with about 20psi of shop air to help get everything primed.

I've never really had a problem, but I've heard people swear by it
 

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we prime 80 trucks a day,was over a 120 and unfortunately that was my job during the difficult years of pressurizing the tank and cracking fuel injector lines.I meant to post this many months ago when I joined .Go to cummins and buy a priming port[2 pieces ]remove the plug at filter and install.purchase a boat motor oil removal pump $30 and it will pull fuel from the tankto the filter.this system works very well and it no longer takes a mech to start trucks at work.

Any chance you have a Cummins part number for that priming port? Also what is the configuration? I mean is it a tee or an elbow or what? Thanks!
 
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