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-   -   If a ferd runs out of oil will it run? (http://www.hdtruckforum.com/showthread.php?t=166)

blacksmoking 04-04-2012 06:10 PM

If a ferd runs out of oil will it run?
 
Ok, i know someone who was looking at a 2nd gen dodge that had been run out of oil and locked up. I all of a sudden had a thought, is that possible with a ford? I know the injection pump is powered by oil pressure so in theory when you run out of oil the engine would shut off correct? Just looking to learn something.

Roush PSD Interceptor 04-04-2012 08:31 PM

Far as I know on the 7.3 the HPOP is driven by a gear run off the cam.
I have heard of oil filters becoming unscrewed and falling off.

Unless there is a no oil pressure fuel cut off it should run until lockup without oil.

blacksmoking 04-04-2012 08:33 PM

I thought the IP ran off Oil pressure. this proves my ignorance about ferds

Agjake11 04-05-2012 01:09 AM

The Hpop runs off the crank but does control the injection pressure. They wont run with out enough oil. Seen many no starts cured with an ipr or replacing a bad icp sensor. Either of these being bad will send a low or bad signal and make the truck not start.

blacksmoking 04-05-2012 08:26 AM

Alright Thanks

06VT365 04-05-2012 08:56 AM

Quote:

Originally Posted by Agjake11 (Post 3096)
The Hpop runs off the crank but does control the injection pressure. They wont run with out enough oil. Seen many no starts cured with an ipr or replacing a bad icp sensor. Either of these being bad will send a low or bad signal and make the truck not start.

Exactly, even a leaking o ring anywhere in the hpo system can cause a no start, like on the oil standpipes, etc.

blacksmoking 04-05-2012 09:09 AM

hmm, interesting. But once it's started, and if something were to pierce the oil pan, would it shut off, or just not start the next time?

06VT365 04-05-2012 01:20 PM

Quote:

Originally Posted by blacksmoking (Post 3107)
hmm, interesting. But once it's started, and if something were to pierce the oil pan, would it shut off, or just not start the next time?

It would eventually, once oil pressure was low enough to not fire the injectors. Weather it would in time to save the engine I dont know.

Basically in a 7.3 or 6.0 fuel system, you have fuel supplied to the Injectors through a fuel rail in the head, you also have high pressure oil supplied to the injectors too. When the computer says an injector should fire high pressure oil is allowed in the top of the injector, once the pressure is high enough it forces open a valve that then allows the fuel to be injected into the cylinder. Thats the basic principal anyways.

So in essence, if the oil pressure is not high enough to open the valve, fuel will not ne fired thus shutting the engine off.

I have a link that explains it much clearer than I can, I will post it up later.

06VT365 04-05-2012 05:27 PM

http://www.blackclouddiesel.com/Tech/howinjectrswrk.htm

Copied from the link above....explains how the HEUI Injectors work.

Understanding how the injectors work on the PowerStroke engine can help in diagnosing a concern with this engine. Older diesels used a hydraulic injection system in which fuel pressurized by the injection pump would actuate the injector. The drawback to this system is that any air which enters the fuel lines will affect the operation of the injectors, or even prevent them from operating. Also, the amount of fuel injected is dependent on the mechanical operation of the injection pump governor, which adjusts volume based on engine load/RPM.
Gasoline engines with electronic injection use a pressurized fuel system and the computer varies the actuation of the injector based on input from various sensors in order to control the amount of fuel to the cylinders. Since gasoline engines have an ignition system to ignite the air/fuel mixture in the cylinders, fuel pressure only needs to be sufficient to supply the injectors and provide an adequate spray pattern to ensure efficient combustion. But a diesel engine uses heat from compression to ignite the air fuel mixture, and this high compression requires high injection pressures.
What has been done on the PowerStroke is both of these systems are used in conjuntion with each other. Fuel is supplied to the injectors through fuel rails inside the cylinder heads. Also supplied to the injectors is high pressure engine oil. As the computer determines that a cylinder should fire it signals the Injector Driver Module. The IDM sends a 110 volt pulse-width modulated signal to the injector solenoid. When the injector solenoid is actuated, it opens a poppet valve which allows high pressure oil to flow into the intensifier piston. The intensifier piston is forced down, pressurizing the fuel inside the injector. When fuel pressure inside the injector reaches approximatly 2700 psi, it causes the injector pintle to rise off its seat and fuel is injected into the cylinder from the nozzel. As long as the poppet valve is open and oil is flowing into the injector, fuel will be injected.

The computer controls how long the injector solenoid is energized (pulse-width, or time on in milliseconds), but it also determines the pressure of the fuel being injected by controlling the pressure of the oil (IPR duty-cycle, or the percentage of time on vs. off--AKA dwell) in the cylinder heads. The computer determines this based on engine load and driver demand by monitoring various sensors. Since the cavity at the top of the intensifier piston is seven times the size of the fuel cavity at the bottom, fuel is injected at a pressure seven times that of the computer-controlled oil pressure--oil pressure 3000 psi = injected fuel pressure 21000 psi. Due to the high oil system pressures, the spring which closes the poppet valve once the injector solenoid is deactivated has to be very strong--and because of this, the solenoid needs to be 110 volts. Once the poppet valve is closed, spring pressure returns the injector to its normal state and the oil is exhausted into the valve cover area to return to the sump.


Hope that helps explain my last post.

blacksmoking 04-05-2012 10:00 PM

that makes more since now.


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