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95 PSD runs fine starts hard

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  #1  
Old 10-03-2007, 05:08 PM
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95 PSD runs fine starts hard

I appologize if this is covered else where but I am trying to post on my way out of work ...

OK ... the truck has been starting a little hard lately ... instead of firing right up it may take like 15 or 20 seconds (if that) of cranking.

last night I ran a bunch of errands and the last one was to get fuel. I filled the tank and the truck wouldnt start back up ... I called a friend and we pushed it away from the pumps ... my wife got there (this is actually her truck ... dont ask) ... and after cranking for a little bit turned the key off ... let it sit for a second and tried again ... this time holding the accelerator to the floor after 25 or so seconds it started to kick over and finally did start ... drove it home (it seemed happy) ... shut it down and tried again same technique ... wouldnt start ... let it sit for another hour or so tried once more and it started reluctantly again ...

we are at a loss ... we recently had the ICP, crank sensor (i think) and the computer replaced ... check engine NEVER comes on ... any thoughts ??

Thanks in advace

Todd and Helen
 
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Old 10-03-2007, 05:25 PM
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it probably the IPR (injection pressure regulator) o-rings. The oil when cold will fill the gap in worn o-rings but when the oil is hot and thin it won't create enough pressure to fire the injectors. Those are classic symptoms of IPR o-rings.
 
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Old 10-03-2007, 06:30 PM
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Originally Posted by tjbeggs
it probably the IPR (injection pressure regulator) o-rings. The oil when cold will fill the gap in worn o-rings but when the oil is hot and thin it won't create enough pressure to fire the injectors. Those are classic symptoms of IPR o-rings.
....What he said......
 
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Old 10-03-2007, 06:31 PM
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x2 on what ^^Tim ^^said. IPR orings for sure.
 
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Old 10-03-2007, 06:33 PM
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are we on x3 or 4? lol
 
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Old 10-03-2007, 06:37 PM
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Originally Posted by c00nhunterjoe
are we on x3 or 4? lol
You're 4.......
 
  #7  
Old 10-03-2007, 07:12 PM
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Would this also occur if the oil was thin from needing to be changed? Unfortunately, it's a little overdue (since July)
 
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Old 10-03-2007, 07:19 PM
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possible but unlikely, usually psd oil that is that far overdue becomes thick and sludged, but aerated oil can be a real biatch, change it first if its that far overdue and drive it a good 40 miles to clear it out and see if ti still acts up
 
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Old 10-04-2007, 07:39 AM
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thanks for all of the replies ... I will keep you updated as to what happens ... if it comes down to it is it a big job to replace these IPR rings ??
 
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Old 10-04-2007, 07:51 AM
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Here you go.
A Powerstroke engine utilizes an electromagnetic valve to regulate the HP oil pressure on the engine to tailor the injection characteristics of the injectors. This valve is called the Injection Pressure Regulator or IPR. Actually, Cat and Ford and Navistar all use different names for it, but I call it the IPR.

IPRs are generally fairly trouble free, but they have been known to become sticky if debris enters the valve or if it suffers from a blown O Ring.

IPR Removal

With a little experience and the right tool, an IPR can be removed from a PSD in minutes.

The IPR is located on the back of the high pressure oil pump, which is located UNDER the fuel filter assembly, down in the vee of the engine. The IPR valve has been largely unchanged since its introduction in 1994.

The easiest way to remove the IPR valve is to build a special IPR removal tool. Said tool is comprised of a 1/2" drive deep 6 point 29mm or 1 1/8" socket with a 4 inch piece of 1" flat iron welded across the back of it. (See picture.) Ordinarily one would just use a deep socket, but the IPR is too deep for the deepest sockets I was able to find. (See picture, not the relative lengths.) Using a 1/2" drive socket will allow the end of the IPR to go where the ratchet stub would have. Furthermore, there isn't much room between the back of the HP oil pump and the front of the turbo assembly, so the thin flat iron increases the available room.
IPR Wrench IPR Wrench & IPR IPR in IPR Wrench

If one could find a deep enough socket, it could be used by itself.
Some Ford dealerships remove the HP oil pump to change/service the IPR. With this tool, it can be done in minutes.
a) To remove the IPR, first find it. The easiest way to do this is to trace the wires from the ICP on the driver's side HP oil rail into the main harness and then out to the IPR deep in the engine vee. You can identify the IPR by its shiny gold colored solenoid. (The ICP and the IPR are not connected, but the wires for both leave the harness at the same point.)


b) Unplug the wire from the solenoid. To do so, you need to flip the connector bail down and pull the connector out. It should come out relatively easily.

c) Remove the solenoid itself. Do this by removing the 3/4" nut that holds the solenoid on the back, followed by the spacer and the solenoid itself.

d) Using the IPR wrench described above, place it on the IPR with the flat iron towards the driver's oil rail. Tap the flat iron with a small hammer towards the rail and the plug should loosen. Give it a few twists with the wrench and then use your hand to turn it out entirely.

e) Removing the IPR will allow most of the HP oil reservoir to drain out into the engine vee. Prepare for this by placing a large amount of paper towel in the vee to absorb the resulting oil. It is also handy to know that a plastic champagne cork fits nicely in the IPR thread and will keep the oil from leaking out.
Once removed, you will have an IPR similar to the one in the picture, without the solenoid.


IPR Disassembly

An IPR is a fairly robust yet intricate item. They are easy to service, but they can be damaged.

An IPR consists of two main parts: a pilot operated valve and an electromagnetic actuator. Each part has been known to give trouble. The electromagnetic actuator is in the end the solenoid was on. The pilot operated valve is the brown end.

To service the unit, first separate the pilot valve from the actuator. To do this, place the IPR in a vice. Then, use a sharp, good quality pipe wrench or similar tool to firmly grab the pilot valve body. (See picture). DO NOT ATTEMPT TO SQUEEZE THE PILOT VALVE BODY TIGHTLY IE IN A VICE OR IT WILL CRUSH AND BE RUINED. A decent working pipe wrench works well. I've opened many IPRs this way without damaging any. The pilot valve slides on the inside of the body, so if it is crushed, it will stick and not work well.
Loosening the IPR

Once loose, the body will separate easily. However, there is a tiny needle in between the body and the actuator that MUST NOT BE LOST. (See IPR Disassembly Picture for a view of the pin.) Normally this pin stays in the end of the body because of the oil that is present, but it has been known to come free. DO NOT LOSE IT.
IPR Disassembly


Once the pilot valve is free of the actuator, disassemble the actuator by loosening the internal screw inside it. (No picture for this, just look inside where the pilot body screwed in.) It takes a big flat screwdriver to remove the internal screw, which is actually a guide for the actuator pin. (See IPR Exploded View Picture). Once the pin and the internal screw is removed (guide actually), shake the actuator body firmly up and down several times to get the piston out.
IPR Exploded View

The IPR is now fully disassembled. It is possible to disassemble the pilot valve itself, but this takes a press and jigs to do it properly.


Servicing

Three things commonly go wrong with the IPR:

a) debris in the pilot valve Using a small screwdriver, gently push in on the end of the pilot valve assembly. You should feel the valve move about 1/8" in and out and return to its seat with a bit of snap. Should the action of the valve be sticky at any point, use a combination of solvent, screwdriver motion and compressed air to clear any debris that may be trapped in its motion.
Operating the IPR

b) debris in the actuator piston area
Thoroughly clean the actuator body, piston, guide and pin. Lubricate them well with a very thin oil or solvent. Assemble the actuator only, but do not tighten. With the solvent as the lubricant, the piston should move freely. I.E. if you shake the actuator assembly, you should hear the piston sliding around freely. This will not happen with motor oil as the lubricant.

c) bad external O Rings.

Examine for wear/damage. There should be a backup ring and an O Ring. The backup ring should be nearest the actuator. Ford sells a rebuild kit consisting of the O Rings and a replacement solenoid nut.

Reassembly

Assemble the actuator end of things. Gently tighten the internal screw (guide). Don't over tighten this. It is difficult to describe how much torque it takes. A little more than the amount for a screw in a computer case.

Place the pilot valve needle in the body. Screw the pilot valve body into the actuator body. Tighten, but don't over do it.

Reinstallation

Reverse of removal. Tighten, but don't over tighten the IPR nut.

NOTE: A PSD WILL RUN INCREDIBLY ROUGH IF THE IPR NUT IS LOOSE. The symptoms of this will make you think you've got multiple bad injectors among other things. You might want to check it for tightness after a few hours of use.
 
  #11  
Old 10-04-2007, 08:18 AM
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X 2 With ...pictures...


Ignore the pic of the pipe wrench on the threads,, it goes on the small barrel....
 
  #12  
Old 10-04-2007, 10:16 AM
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WOW excellent ... thanks guys ... this looks like something I should be able to handle ... not that being said ... the Ford dealers around my area do NOT admit to there being a rebuild kit ... if it exists is there a part # that you know of or what size are the o-rings so that I can just buy the o rings
 
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Old 10-04-2007, 11:47 AM
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You can use the link in my signature for PSD part #'s too. Book mark it for future reference.

IPR O-Ring Kit (for when IPR valve replacement is not required)
(Ford) F6TZ-9C977-AN (F6TZ-9C977-AA?)
(International) 1825806C92 (1825806C91?)

IPR Injection Pressure Regulator
(Ford) F4TZ-9C968-C (engine serial no. 187099 & before or pump no. 255C92)
(International) 1824982C91 (engine serial no. 187099 & before or pump no. 255C92)
(International) 1833798C91 (All Years ???) latest part number
(Ford) F81Z-9C968-AA (engine serial no. 187100 & up or pump no. 247C91)
 
  #14  
Old 10-22-2007, 01:53 PM
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OK ... update time ... I finally got to work on this thing ... after alot of searching I found the IPR and got it pulled ... It sounds like mine is positioned a little different the the write up ... and its easier if you pull the fuel filter housing but other than that the directions are GREAT !! thanks guys ...

I will be cleaning the valve as well as replacing the orings ... I will update again after its installed ... thanks again guys
 
  #15  
Old 11-01-2007, 03:10 PM
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WOW .. .nice boat Cuda !!!!

OK another update ... I got the rebuild kit (the one ford says doesnt exist ... for $25) ... cleaned the valve, reassembled it, put on the o-ring kit (which was WAY easier than I was lead to believe by a friend of mine), and installed the thing into my truck ... besides the PITA the fuel filter bowl gave me going back on and the boneheaded mistake of NOT plugging the IPR back in ... it went pretty smooth. The truck runs GREAT now ... well as good as it did before but now you can start it warm. The two little "o-rings" were blown out just as y'all said ... thanks for all your help guys !!!!
 


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