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Discussion Starter · #1 ·
JUST TO LET EVERYBODY KNOW WE HAVE SEEN SOME RODS GO AWAY ON 6.4 WITH SOME OVER FUEL PROBLEMS WHEN THE INJECTORS FAIL IN THE DISCHARGE....... FORD IS LOOKING FOR ANY REASON TO CANCEL WARANTY REPAIRS WE HAVE HAD LOTS OF INFO COMING FROM THE COMPANY.....
i WOULD GO EASY ON THE HOP UPS INTILL WE HAVE THE BASE FUEL SYSTEM RIGHT..... THE SUPPLY TO THE HIGH PRESS PUMP IS JUST 3 PSI AND 1/2 PSI LOSS IN PRESS CAN TAKE OUT THE PUMP AND MOVE TRASH INTO AN INJECTOR AND IF THAT INJECTOR FAILS IN DISCHARGE IT WILL HYD A CYL AND TAKE OUT A ROD. ANY MODS AT THAT TIME WILL VOID YOUR WARANTY


My question obviously centers around the supply to the high pressure pump.
Is this pressure factor considered, examined and stabilized with the SCT tune?

Thanks very much.
 

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Innovative: I'm told they do not increase the pressure but rather massage the pulse width and pulse timing. Can you also confirm?

George C: Where did that info come from? Sounds very strange that the supply is only 3psi, I almost don't believe that. If the injector clogs/fails then how could it hydraulic a cylinder? Unless they are saying that it increases the fuel to some other cylinder which causes it to hydraulic lock...... But then again these are common rail... wow, Im lost.
 

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Discussion Starter · #3 · (Edited)
Innovative: I'm told they do not increase the pressure but rather massage the pulse width and pulse timing. Can you also confirm?

George C: Where did that info come from? Sounds very strange that the supply is only 3psi, I almost don't believe that. If the injector clogs/fails then how could it hydraulic a cylinder? Unless they are saying that it increases the fuel to some other cylinder which causes it to hydraulic lock...... But then again these are common rail... wow, Im lost.

I'm lost too, but it appears the 3 lb supply is to the pump, not the injectors. It seems the pump supply pressure is extremely critical.
I got it from here:

Innovative tunes, 500rwhp? - Page 2 - Powerstroke Nation

I know there are no guarantees, but the decision to kill off the warranty on a 15K engine makes me want to cover these topics.
Innovative seems to be the most respected and knowledgeable voice on SCT tunes. Hopefully, he can shed some light on this topic and teach us something.
 

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Hrm... lets dissect this:

(1) he is a first time poster
(2) his nickname is SrMasterFordTechnician, (I mean.... really)
(3) his post is right in the middle of a pro-innovative 500hp announcement thread.

Looks fishy to me. It smells of someone trying to keep people from buying Innovative's product/tuning... doesn't it?
 

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Discussion Starter · #5 ·
I believe it's a simple question that should be asked, and probably has a very good answer coming from Innovative.
Why try to come up with a reason for questioning the author?
Let Innovative question the authenticity.
 

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Can those injectors push enough fuel to actually hydro-lock a cylinder....if they can thats impressive. I mean wasn't the flame thrower in the early 6.4's caused by a leaking injector or stuck open injector or something like that??:dunno:
 

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Guys, I will openly profess to knowing almost zero about the 6.4's. With that said, I have been doing some reading and research on them as I have considered strongly buying one. I also read the aforementioned post on PSN. It doesn't look to me to be that far-fetched of an idea to have and injector hang open or nozzle problems that could put enough fuel into the cylinder to hydro lock it. I know with the 7.3's that if you pull an injector, you should pull the glow plug and roll it over a few times to get the liquid out to ensure you don't hydro-lock it.
On another note, I was at one of our local dealerships yesterday and talked to their diesel expert about what kind of problems he was seeing with the new 6.4's. He said something that was interesting to me. He told me that he had recently had to replace the entire fuel system on a truck that the owner had filled with gasoline :doh: to the tune of $8k worth of repair bill. Ford did not pay as this was caused by the owner. He did say that the owners insurance company did bail him out. I'll bow out now, and continue to watch and learn.
 

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Sorry I can't help ya much with the 6.4 stuff, but just wanted to let ya know I sent this thread to Eric (IDP) and hopefully he'll be able to respond soon.:thumb:
 

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Discussion Starter · #9 ·
The way I read this thing, it's not about the injectors causing a problem, it's the pump failing under inconsistant feed pressure, and the chain of events that follow...
If the pump has any inconsistancies in pressure (3 lbs), the pump itself will begin to fail, and the debris from that resulting failure is what the injector will be digesting, and then failing itself. Then, the damage of hydrolicking is the end result.

The problem is this, if Ford has a book on this type of situation, they will follow it right back to the owner's use of a tuner.
If SCT or any other tuner has taken this pump feed pressure variable into consideration, and has taken steps to make sure the pump line pressure remains totally consistant within stock parameters, we can all rest easy. If this particular situation has not been considered and addressed, there is a potential catastrophic problem just waiting to happen.
And I guess I don't have to tell you who will be holding the bag....
 

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The way I read this thing, it's not about the injectors causing a problem, it's the pump failing under inconsistant feed pressure, and the chain of events that follow...
If the pump has any inconsistancies in pressure (3 lbs), the pump itself will begin to fail, and the debris from that resulting failure is what the injector will be digesting, and then failing itself. Then, the damage of hydrolicking is the end result.

The problem is this, if Ford has a book on this type of situation, they will follow it right back to the owner's use of a tuner.
If SCT or any other tuner has taken this pump feed pressure variable into consideration, and has taken steps to make sure the pump line pressure remains totally consistant within stock parameters, we can all rest easy. If this particular situation has not been considered and addressed, there is a potential catastrophic problem just waiting to happen.
And I guess I don't have to tell you who will be holding the bag....
I think I agree with everything you are saying. That's the way I read it also.
 

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Can those injectors push enough fuel to actually hydro-lock a cylinder....if they can thats impressive. I mean wasn't the flame thrower in the early 6.4's caused by a leaking injector or stuck open injector or something like that??:dunno:
yes they can i have a job 1 08 f350 and with 9000 milles on and i have had #6 cyl, piston and rod replaced. stock truck no chips no exhaust no nothing!
 

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yes they can i have a job 1 08 f350 and with 9000 milles on and i have had #6 cyl, piston and rod replaced. stock truck no chips no exhaust no nothing!
Now that is interesting. Glad it was under warranty.
 

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^so a tuner doesnt cause or lead to this issue. It should be warranty tuned or not
 

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It takes very little fuel in a closed cylinder to hydrolock it.

What made the pump fail is the question that will be discussed and the warranty coverage will depend on that decision.

What is troubling is the fact that a failed pump means damaged engine. Why is there not a screen or something to prevent catastrophic failure?
 

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ive seen a 6.4 pulled out of the truck with a bent rod sitting on top of the motor all crated up ready to ship back to ford
 

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I have the 6.4 bible downloaded on my computer but it is also available here.
http://www.powerstroke.org/forum/general-6-4l-discussion/50052-powerstroke-6-4l-bible.html
The reason I am adding this is because if you open the fuel system file there is a very good simplified schematic and good explanation of the system. This guy is right about the 3 +/- .5 psi., but as far as a tune causing a problem with this I just don't believe. The pressure is regulated by a mechanical poppet relief valve in the filter housing routing fuel back to the HFCM, has no communication with the computer. Also if you read on down is says the cracking pressure is 2psi. and actual pressures may be lower or higher.

I guess to get to the point, I just don't believe it is as critical as it is being portrayed and having a tune or any other mod. is going to have 0 effect on the operation of this portion of the fuel system. I'm not saying it "can't" fail but if it does it has nothing to do with a mod. J.M.O.

737tdi
 

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Discussion Starter · #17 ·
I guess to get to the point, I just don't believe it is as critical as it is being portrayed and having a tune or any other mod. is going to have 0 effect on the operation of this portion of the fuel system. I'm not saying it "can't" fail but if it does it has nothing to do with a mod. J.M.O.
If it is strictly a mechanical feed and monitored by a mechanical valve, then I agree. There can be no way a tuner could alter the pressure of the fuel supply. If all is true, I wonder how Ford can attempt to pin the fuel supply pressure directly to a tuner.
Is there anything else directly or indirectly changing fuel pressures anywhere else in the supply system that could be somehow altered by a tuner's affect?
 

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Unless..

the fuel used is more than can be supplied from the tank and it starves the pump. This is highly unlikely on this truck in my opinion. After modifying my old Chevy truck however the fuel pressure would go to 0 psi at the injection pump when it was run hard and a better or second lift pump is needed to maintain the required pressure to prevent pump damage.

The problem can't be ruled out by assumption. Somebody needs to install a gauge and test it.
 

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Discussion Starter · #19 ·
Unless..

the fuel used is more than can be supplied from the tank and it starves the pump. This is highly unlikely on this truck in my opinion. After modifying my old Chevy truck however the fuel pressure would go to 0 psi at the injection pump when it was run hard and a better or second lift pump is needed to maintain the required pressure to prevent pump damage.

The problem can't be ruled out by assumption. Somebody needs to install a gauge and test it.
Considering the instant fuel draw when an agressive 200-250 hp tuner starts drawing fuel when the driver floors it..

This is very possible.
 

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This info. is straight out of the Ford Powertrain Control/Emissions Diagnosis Manual for our trucks. The HFCM supplies 5 to 10 p.s.i. to the secondary fuel filter at idle, as said earlier the pressure relief/return valve inside this filter housing is set to relieve at 3 p.s.i.. So this indicates positive pressure to the filter thus to the High pressure pump. Also if you look at the HFCM it relieves pressure at 24 p.s.i. indicating it has alot more pressure capability.

"After the low pressure fuel is filtered by the secondary fuel filter, it enters the high pressure fuel injection pump. When the fuel reaches the high pressure pump, it's pressure is stepped up by the transfer pump. The transfer pump is internal to the high pressure fuel injection pump and is driven by the high pressure fuel injection pump main shaft. A portion of the fuel leaving the transfer pump flows to the lubrication valve which allows the fuel to lubricate the mechanical components of the high pressure injection fuel pump. Fuel that is not used for pump lubrication is directed to the fuel volume control valve."

My reason for adding all of that is the last sentence, this is all happening prior to any control by the pcm, and is also before any fuel reaches the high pressure portion of the pump/fuel volume control valve which of course is where the fuel pressure is then increased up to 24,650 p.s.i..

As I see it the last thing to be starved of fuel would be the lubrication portion of the high pressure pump, if there is a fuel starvation event I believe the pump would simply not be able to supply the high pressure/volume to the fuel rails/injectors.

I'd like to see some more input by maybe some actual diesel engineers. I am merely a aircraft mechanic with a working knowledge of turbine fuel systems/main engine controls and a shade tree mech..

737tdi
 
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