I am no expert on the 4p10, but generally there is no way the return side of the fuel system can bleed the injection pump itself. Since you replaced the pump and removed the injectors, it seems like you need to crack the high pressure lines at the injectors, crank until you see fuel come out of all of them, then tighten and crank until it starts. apologies if you have already tried this. edit, the logic being that the pump is likely air-bound and cannot prime to create sufficient rail-pressure. do not have any body part near the loose lines, as rail pressure is high and can cause injection wounds. best of luck to you. i have a 90 FG and love it.
So - I believe the output side of the injection pump feeds the rail, which returns to the tank through the regulating valve. The input of the pump is force fed by the electric lift pump, so there should be no air bound anywhere. On older diesels you do need to crack injectors to let the air out.
@@BruceandKrista Give it a go. At a minimum, it will confirm that the cp4 is in fact receiving fuel from the lift pump, the fuel control solenoid is sending fuel through the pump and pressurizing the rail. If fuel comes gushing out it will eliminate the pump from the equation and give credence to the bypassed injector supposition. If fuel is not gushing out, then the pump is not moving sufficient fuel, likely ecm is not energizing the fuel control in CP4, indicating your aberrant rail pressure reading is a failed rail pressure sensor.
I had that exact problem on my4p10. injector number 3 laking compression. And won't starting problem after replacing the high-pressure fuel pump. I did everything that you did and still won't start. (Noted that I have no clue what the problem with slow cranking) The problem was that high pressure fuel pump CP4 MIND BLOWING 🤯 that's why it's not started After replacing the pump and I only bleed with electric fuel pump And only crank ones. It's fired, right up If I were you I will be fired the parts cannon and replace a another CP4 pump
After watching a few of the original no start vids it's clear you have covered the bases here. Agree with comments regarding bleeding pump, maybe you can pull fuel through it with vacuum sucker ? Also makes me question your air supply. Could something get into your intake ? A rat, a stray rag ? Stuck turbo ? fuel AIR and compression ?
2013 lift pump is outside the tank - it’s been replaced and is providing 60PSI, I can monitor this as I’ve added a dash mounted fuel supply pressure gauge. Entire fuel rail has been replaced, so though possible, it’s unlikely that it’s the regulating valve in the rail… I’ll be ruling it out soon! Thanks for the suggestions!
Bruce, have you checked to make sure your exhaust brake is not activating? It may generate enough backpressure to prevent start in some circumstances. Maybe you've already checked this, I've only seen 90%, not 100% of your tireless efforts, so maybe I've missed it. Soldier on!
Sorry, another long and detailed comment. I'll keep saying it until I'm blue in the face - but it is now long past time you got a pressure gauge on that fuel rail. All four injectors should be doing what number three is if they are firing correctly. If you don't test them by holding one in your hand and feel and hear it click, the other evidence of them firing is the bypass flow. Seeing number three do what it is suggests to me the injectors are being energised by the ECU, but there is insufficient internal pressure in the injectors for them to cycle. As counter-intuitive as it sounds, the injector pintle (the valve that open and closes the nozzle) needs good fuel pressure to seal and thus cycle, and the solenoid dumps the pressure that keeps the pintle closed via the bypass - hence my earlier comment about checking the bypass flow. At idle you should be seeing about 10ml per injector per minute out of the bypass. Fuso will have specific figure at a specific rpm over a specified time frame, but 10ml is a good indication. A super easy (and cheap) way to check is to find four syringe bodies with a nozzle that fits snugly in the bypass barb. All four injectors should fill the syringe body at around the same rate at idle - more or less from one injector is a bad thing. It could be that number three has just enough variation in wear to the others that it is building up just enough internal pressure to fire - hence the little spurts from the bypass. If that's the case, your fuel rail pressure is way too low. I'd be interested to know why that spare engine died? If it was pulled as a non-runner it's possible you fitted a dead high-pressure pump and that's why it still wouldn't start. Don't stress about the starter fluid washing the oil from the cylinder walls. Unless all of this is getting too much and out of frustration you emptied several cans of the stuff into the engine off camera when we weren't watching, there was nowhere near enough used in that clip to cause any damage. Cast iron liners retain lubrication pretty well and it would take a lot before you washed enough out to actually damage anything 👍
High pressure gauge is en-route in the mail ! I’ve done a few more things in the mean time (next video). Also tried getting an injector return measuring tool set, but though it advertised fitting the injectors, it didn’t. You are right Fuel rail pressure isn’t building, I’m working on why. One possibility is the rail pressure regulating valve is sending all the pressure back to the tank. Only a few things left that it can be at this point - we are getting close!
@@BruceandKrista The syringes work a treat, and they're cheap, just a little messy when you pull them out after the test is complete. Does your diagnostic tool display the fuel pressure the ECU is calling for? If you have no engine ECU fault codes and it is calling for full pressure but there is none in the rail, then it should be down to a simple mechanical fault. It's reassuring to see number three bypassing fuel the way it is - fingers crossed the solution is very close.
Haven't heard of fuel return suppling fuel to the injectors. The injector need Hi Press pump to supply injectors. I think my Ford tractor had 1000-2000 psi ? When my injector pump started an internal leak the eng. would not run. I would open all 4 feed lines and see what comes out. You may be on the right track with a broken HP pump drive.
Hey Bob - it’s a bit of a different configuration on this engine - the electric pump feed splits in two, so it can back feed the whole system. Had me a little confused when I first started working on it!!
Sounds like your batteries are not that good,check your voltage while cranking normally it drops but on some diesels if it drops below a certain voltage the computer will not let the injectors fire . I went though this on my Ford 6.0 l had the Ficum and a few sencers replaced but 2 new batteries really made a huge difference. Maybe you’ve done this already but clean all connections fully charge and load test each battery outside the vehicle ,or the cable ends could be bad. I think that engine has to crank way faster to start and those batteries are not going to do it . I really like your build and think the new scanner is great. Good luck
I am no expert on the 4p10, but generally there is no way the return side of the fuel system can bleed the injection pump itself. Since you replaced the pump and removed the injectors, it seems like you need to crack the high pressure lines at the injectors, crank until you see fuel come out of all of them, then tighten and crank until it starts. apologies if you have already tried this.
edit, the logic being that the pump is likely air-bound and cannot prime to create sufficient rail-pressure. do not have any body part near the loose lines, as rail pressure is high and can cause injection wounds.
best of luck to you. i have a 90 FG and love it.
So - I believe the output side of the injection pump feeds the rail, which returns to the tank through the regulating valve. The input of the pump is force fed by the electric lift pump, so there should be no air bound anywhere. On older diesels you do need to crack injectors to let the air out.
@@BruceandKrista Give it a go. At a minimum, it will confirm that the cp4 is in fact receiving fuel from the lift pump, the fuel control solenoid is sending fuel through the pump and pressurizing the rail. If fuel comes gushing out it will eliminate the pump from the equation and give credence to the bypassed injector supposition. If fuel is not gushing out, then the pump is not moving sufficient fuel, likely ecm is not energizing the fuel control in CP4, indicating your aberrant rail pressure reading is a failed rail pressure sensor.
Bruce has the fortitude of a WARRIOR! an All Terrain Warrior.
Well I mean so far it’s kind of “no terrain” but we will get to all terrain at some point! 🤣
Love your "Never give up spirit Bruce"!
You are a Warrior brother my brother.
God bless.
“walk away”….couldnt agree more. #duramaxSWAP
LOL - slightly more work, but not much🤣
I had that exact problem on my4p10.
injector number 3 laking compression.
And won't starting problem after replacing the high-pressure fuel pump.
I did everything that you did and still won't start. (Noted that I have no clue what the problem with slow cranking)
The problem was that high pressure fuel pump CP4
MIND BLOWING 🤯
that's why it's not started
After replacing the pump and I only bleed with electric fuel pump
And only crank ones. It's fired, right up
If I were you I will be fired the parts cannon and replace a another CP4 pump
I’m close to thinking the same - just need to do a few more tests to confirm before ordering a pump!
@BruceandKrista good idea
@@BruceandKristaHey, I just fixed my 4P10 that had a CP4 disaster
Is there's a way we can chat privately
I will help with the diagnosis
After watching a few of the original no start vids it's clear you have covered the bases here. Agree with comments regarding bleeding pump, maybe you can pull fuel through it with vacuum sucker ? Also makes me question your air supply. Could something get into your intake ? A rat, a stray rag ? Stuck turbo ? fuel AIR and compression ?
Checked the air intake when we tried the ether, bypassed the airbox completely. I could try pulling fuel…
Electric lift pump in fuel tank shoiul;d be able to hear with key on.then check DRL at front of fuel rail give it a love tap before replacing.
2013 lift pump is outside the tank - it’s been replaced and is providing 60PSI, I can monitor this as I’ve added a dash mounted fuel supply pressure gauge. Entire fuel rail has been replaced, so though possible, it’s unlikely that it’s the regulating valve in the rail… I’ll be ruling it out soon! Thanks for the suggestions!
Bruce, have you checked to make sure your exhaust brake is not activating? It may generate enough backpressure to prevent start in some circumstances. Maybe you've already checked this, I've only seen 90%, not 100% of your tireless efforts, so maybe I've missed it. Soldier on!
I’ll be checking this soon - thanks for the idea!
Sorry, another long and detailed comment.
I'll keep saying it until I'm blue in the face - but it is now long past time you got a pressure gauge on that fuel rail. All four injectors should be doing what number three is if they are firing correctly. If you don't test them by holding one in your hand and feel and hear it click, the other evidence of them firing is the bypass flow. Seeing number three do what it is suggests to me the injectors are being energised by the ECU, but there is insufficient internal pressure in the injectors for them to cycle. As counter-intuitive as it sounds, the injector pintle (the valve that open and closes the nozzle) needs good fuel pressure to seal and thus cycle, and the solenoid dumps the pressure that keeps the pintle closed via the bypass - hence my earlier comment about checking the bypass flow.
At idle you should be seeing about 10ml per injector per minute out of the bypass. Fuso will have specific figure at a specific rpm over a specified time frame, but 10ml is a good indication. A super easy (and cheap) way to check is to find four syringe bodies with a nozzle that fits snugly in the bypass barb. All four injectors should fill the syringe body at around the same rate at idle - more or less from one injector is a bad thing.
It could be that number three has just enough variation in wear to the others that it is building up just enough internal pressure to fire - hence the little spurts from the bypass. If that's the case, your fuel rail pressure is way too low. I'd be interested to know why that spare engine died? If it was pulled as a non-runner it's possible you fitted a dead high-pressure pump and that's why it still wouldn't start.
Don't stress about the starter fluid washing the oil from the cylinder walls. Unless all of this is getting too much and out of frustration you emptied several cans of the stuff into the engine off camera when we weren't watching, there was nowhere near enough used in that clip to cause any damage. Cast iron liners retain lubrication pretty well and it would take a lot before you washed enough out to actually damage anything 👍
High pressure gauge is en-route in the mail ! I’ve done a few more things in the mean time (next video). Also tried getting an injector return measuring tool set, but though it advertised fitting the injectors, it didn’t. You are right Fuel rail pressure isn’t building, I’m working on why. One possibility is the rail pressure regulating valve is sending all the pressure back to the tank. Only a few things left that it can be at this point - we are getting close!
@@BruceandKrista The syringes work a treat, and they're cheap, just a little messy when you pull them out after the test is complete. Does your diagnostic tool display the fuel pressure the ECU is calling for? If you have no engine ECU fault codes and it is calling for full pressure but there is none in the rail, then it should be down to a simple mechanical fault. It's reassuring to see number three bypassing fuel the way it is - fingers crossed the solution is very close.
Haven't heard of fuel return suppling fuel to the injectors. The injector need Hi Press pump to supply injectors. I think my Ford tractor had 1000-2000 psi ? When my injector pump started an internal leak the eng. would not run. I would open all 4 feed lines and see what comes out. You may be on the right track with a broken HP pump drive.
Hey Bob - it’s a bit of a different configuration on this engine - the electric pump feed splits in two, so it can back feed the whole system. Had me a little confused when I first started working on it!!
He needs lots of coffee!
Always!
Wondering about the fuel, I'm assuming its newer & from a trusted retailer ?
Fuel is clean and clear - same fuel it ran on right before it quit.
Is this the episode?
It’s one of them
I'm goosed with that f-you-so! I have just written a letter to Santa and asked him to drop you off a Tonka truck when he is in your area.
PERFECT 🤣. Thanks!
Sounds like your batteries are not that good,check your voltage while cranking normally it drops but on some diesels if it drops below a certain voltage the computer will not let the injectors fire . I went though this on my Ford 6.0 l had the Ficum and a few sencers replaced but 2 new batteries really made a huge difference. Maybe you’ve done this already but clean all connections fully charge and load test each battery outside the vehicle ,or the cable ends could be bad. I think that engine has to crank way faster to start and those batteries are not going to do it . I really like your build and think the new scanner is great. Good luck
I think you missed the part of the video where he tested the batteries because he said - they don’t sound right
Yep, batteries are good
😢 This is getting depressing.
Haha! But each thing that doesn’t fix it narrows down the things that are left that it could be! Have to be getting close now!