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Discussion Starter #1
After getting air in the fuel lines do I need to bleed all four cylinders, or can I get a start with only bleeding three?
Thanks for suffering this totally NOOB question.
 

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Start by making sure your fuel line is free of air to the IP then start one line at a time on the injectors until it takes off.

Your could do yourself and others a favor by doing some reading before posting a question that has been asked, and answered, many times over. A quick Google search would have worked. YouTube also has many tutorial videos showing how to prime a fuel system properly.
 

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Discussion Starter #3 (Edited)
Thanks for the response. I understand "how" to bleed a diesel motor properly. The question was, will a 4b that has been improperly bled, start w/only 3 injectors having been cracked. Thanks again.
 

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You may get lucky we ran a p pump out of fuel and it fired with only priming lift pump.l
Primed and started mine from bone dry/complete rebuild after bleeding only one cylinder. It only needs to start missfiring (even only on one cylinder) before it'll clear the other injectors. That's just my experience, I'm sure others have had to bleed all 4.
 

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Primed and started mine from bone dry/complete rebuild after bleeding only one cylinder. It only needs to start missfiring (even only on one cylinder) before it'll clear the other injectors. That's just my experience, I'm sure others have had to bleed all 4.
I can second this. Even on my 6BT, once I have bleed #1 it will usually start roughly and clearer the other 5 on its own pretty quickly.
 

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Agreed with the above. Start cracking lines at #1 while cranking, then move back to #2 and #3 then #4 until it starts running. Once she's running (rough at that point), she'll clean up if you give it some throttle.
 

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I cracked 1 then 3 while cranking until it sprayed the exhaust. She jumps around, but fires up lol
 

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We run 4BTs and JD Powertech 4.5's in our forklifts and I have started both with only using the lift pump when wrenches were not available. Yeah it takes about 300 strokes of the finger plunger to get them to cough and fart but eventually they clear out and run on all 4.

If I do have a wrench I just crack all the injectors loose and crank until fuel leaks out of them, then tighten and crank till it fires off. Usually it will be running rough for just a little until residual air is pushed thru.
 
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