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6.4 crank no start

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I have a maxx 7 (6.4) IH chassis, that I have taken over the diag on. Crank no start, died on the road. The previous guy replaced the frp sensor (don't know why) and they opened the fuel system. Some of the crank cycles the frp was reading 10,000-20000psi when the desired was around 4500psi. Other times I had 5-100psi. I would get a fault for unable to build fuel pressure when cranking - even though I had the 15000psi reading. Started off by checking my low pressure fuel - bled the air from the system and now have about 3 psi (in spec) Checked the inlet restriction - ok at 3" No air in the system up to the secondary filter at this point. I am in the process of removing the turbo to access the fuel line at the pump to be sure I have no air at the pump. My question is with the frp readings. Can I get a high pressure reading with air in the pump? The fpcv allowing a higher duty cycle because of the air, then the reading spikes? Some tips on diagnosing the pump would be helpful.

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What is the fuel quality like?

 

If the FRP sensor is jumping around all over the place, I'd have a look at that 15-way connector that comes out of the rockerbox and make sure that thing's all gravy and not contaminated or loose or somethin. Assuming the FRP is under the valve cover like it is on a 6.4

 

You got all the other particulars to support it running? Proper RPM signal, cranking speed, airflow, etc?

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Spent some time on this today. Removed the turbo to access the fuel lines and bleed the system thoroughly. I have smoke out the right exhaust manifold, nothing out the left. FRP is much steadier now that I bleed the system at the pump. Installed block off plugs at the hpp to isolate each bank - still does not start. Performed manual compression test - all at 350 psi, all glow plugs good, no mist coming out of the glow plug ports while cranking to perform the compression test.

I have a fuel pulswidth reading - this indicates cam and crank syn. and operation (for us anyways)

Cranks about 235 rpm

No Maf on ours.

Next step is to pull the valve covers, remove an injector line and catch the fuel in a coffee filter - Guessing to check for metal from a failed pump????

I checked the 15 pin at the rocker box - no corrosion/water etc.

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I removed an injector line on each bank and cranked the engine while catching the fuel in a coffee filter. I could see specs of metal. Maybe 5 specs from each side. Removed an injector, connected the fuel line and electrical connector and cranked the engine. No fuel coming out of injector even though my rail pressure is about 5,000psi and I have fuel pulswidth. Hotline wants a set of injector installed. I don't see anything in the fuel tank so I am suspecting a high pressure fuel pump to failing. Hotline won't go for the fuel pump just yet.

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I replaced the 8 injectors today, primed the fuel system and fired it up. Let it run for 15 secs, then shut it off and contacted hotline to see if I could put a pump in it (didn't want to contaminate the new injectors) They state that they have never seen a high pressure fuel pump cause a metal in fuel condition. The contaminants come from the fuel tank. I asked how does steel (what I found in the coffee filters) come from an aluminum fuel tank. They did not reply back. It is going back together and being returned to the customer... for now.

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I am finding a lot of replies from the Hot-Line lately make no sense what-so-ever and contradict a lot of things they have done in the past, things that are common knowledge. We recently applied for assistance for a customer that had a fuel tank rust out. Ford replied that they do not have problems with fuel tanks. Excuse me?

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