One of the most common problem areas with the 6.0L engine is the high pressure oil system.
Background information on the high pressure oil system (and note that the diagrams show the '05 and up system as identified by the style of HPOP):
To begin this thread, the video linked below is a good way to learn the system (but please note that DTR is not current in his saying that Standpipes are rare to fail. Now-days, they are probably the most frequent component to find failed). Also, in the video linked below, note that DTR mentioned that he had a bad OEM IPR right out of the box and it "kicked his butt" trying to do the repair. Lastly, please be aware, that due to the age of the 6.0L now, more and more issues w/ the '05 and up HPOP are being documented (still not common, but time and miles take their toll).
Also, here is a link to another thread I did on this topic:
Leaks are common - especially with the late 04 and up oil rails (as mentioned earlier, sadly standpipe issues are FAR too common now), and the 05 and up (original) STC fitting. Even with no leaks, the IPR valve could have failed or be stuck open from debris ..... OR the HPOP could have failed.
This thread is not about identifying leaks however (I do mention a bit about more leaks later on, but it is not the focal point of the thread)! Instead it is about identifying a bad HPOP. Note that if the IPR valve is identified to be leaking, then remove it and look for debris on the IPR screen. If debris is found on the IPR screen, or inside the IPR valve, you need to identify this debris!! If it is metal, then identify what type of metal (if you can) is important.
If the IPR contains METAL debris (or has it on the screen, then this very well might be a sign of a failed or failing HPOP. If it is from the HPOP, typically the metal will be brass and non-magnetic (pay attention to the metal coloration). Early on Ford stated that slight amounts of metal on the IPR screen does not necessarily warrant HPOP replacement, but I lean to saying that even slight amounts would very likely justify replacement of the HPOP (regardless of year model or pump type).
With HPOP failures (very similar to leaks in the High-Pressure oil system), you will see a lack of engine power, AND high IPR commanded duty cycle (and often the actual ICP will be less than desired ICP).
From what I understand, the only "100% sure" way to identify a bad HPOP is to remove the pump and remove the cover and rotating assembly to inspect/test it. That said, if you open the pump you most likely make junk out of it. So, we need other ways to condemn the HPOP!
NOTE - the axial pumps were only used on the 7.3 and the '03 - '04 engines in the 6.0L. The '05 and up pumps were a "4V" style cam shaft operated piston pump that is more robust than the axial pump (thanks to @Hydro for this note).
The 03 and 04 HPOPs have a much higher failure rate than the 05 and up (cast iron) pumps. EVEN SO, the 05 and up HPOPs CAN AND DO fail occasionally!
Note that even though the late 04 engines had the change to the wavy oil rails (AND the HPOP capacity was increased slightly), the HPOP in that model year still had the weaker swash plate design. The HPOP "mechanical" design was not changed until the 05 model year and as such, the "failure prone" STC fitting was introduced in that model year also (unfortunately). The early model year (03-04) HPOP discharge piping DID have a type of snap-to-connect fitting, and it does fail occasionally. Ford came out with an updated "J Tube" that improved the reliability of this model year HPOP discharge fitting, and this updated part has been very reliable, a worthwhile upgrade! That said, the '03 and '04 J-tube failure (o-ring) was not the same as the failure prone 05 and up STC fitting). When people talk about a failed STC fitting on the HPOP discharge, they are referring to the 05 and up pump. When it fails, it can break apart with enough force to damage the rear cover, so it is something best done proactively IMO.
Enough about leaks for now!
Here is where I will happily send some compliments to CNCFab. Their upgraded aluminum (old style) HPOP has turned out to have a TREMENDOUS record for reliability. It and the DieselSite HPOP (Adrenaline) are the only two choices to consider if you are in a repair or if you want to upgrade the '03 or '04 HPOP proactively. The HPOP from CNC Fab is a better value and they have better customer service - hands down! For '05 and up HPOPs, I think OEM is still the best.
Pretty much everyone is aware of the air testing used to identify a leak in the High-Pressure oil system. The air test can be done two ways: from the ICP sensor port, OR from the IPR valve port. Typically, air testing SHOULD BE DONE before thoughts turn to an HPOP failure!! The best place to introduce air when suspecting a bad HPOP is from the IPR valve port (with the special test fitting). This eliminates ANY possibility of a bad IPR valve influencing the test results!
Identifying a bad HPOP is more difficult than finding a leak. In fact, a bad HPOP is TYPICALLY identified only after everything else in the High-Pressure oil system has been determined to be working as it should (ie low pressure oil pressure is sufficient AND NO LEAKS are present).
The most common method to identify a bad HPOP is when conducting the air test.
Note - if you have a leak in the high pressure oil rails, STC fitting, or even from an injector, it is best to repair these first, and then repeat the air test.
First remove the oil filter housing cap and then remove the oil filter. Then have someone hold down the oil filter housing drain valve, and introduce air into the high pressure oil system. The reason to hold down the oil filter housing drain valve is because sometimes "air sounds" from the crankcase can interfere with this test (say if air were to leak from other components like the standpipes). Holding down the oil filter housing drain valve keeps any air that might be in the crankcase from flowing into the oil filter housing.
Shop air at 150 psig - 175 psig air is recommended (there is no reason to go higher). When applying this air to the system, if air leakage OR a gurgling sounds are heard from the oil filter housing, then that means the air is most likely flowing backwards through the HPOP. This should not be possible w/ a healthy HPOP.
In addition, air flowing in reverse through the HPOP will also be able to be identified if air flows out of the turbo oil supply line (aerated oil will be expelled). Note that this is the turbo oil supply line, not the drain line!
Back to the testing process for identifying a bad HPOP (HPOP installed). Reverse flow of air when doing an air leak test is the common way documented to condemn an HPOP. I must say that this really needs a prerequisite mentioned:
The difficulty with interpreting this test is that air may not always flow backwards through a failed HPOP in every situation (HPOP internal position is a potential factor in the success of this test). It may leak in one orientation, but not in others. SO - if reverse flow of air is detected, it is most likely a failed HPOP. If reverse flow of air is not detected, then more testing is required.
In the case of no air detected with the HPOP installed in the engine, the next step is to bench test it (ie remove the HPOP and do the air test with it in a vise on the bench). When testing on a bench, the HPOP gear can be rotated to test for air leakage in all of the pump "internal positions". Sometimes when you try to slowly rotate it by hand, you might hit a "dead spot" with it (won't turn anymore). The HPOP is bad if this happens.
The second method to identify a bad HPOP is not as much of a "sure-thing" as the first ....... but it MIGHT BE easier.
NOTE - I read this on the forddoctorsdts.com web site, that site is an AMAZING resource! Thank you FordDoctor!
A bad HPOP will often times cause a repetitive fluctuation in the pressure of the High-Pressure oil (ICP pressure reading).
To detect this, you need to be confident that your ICP sensor is reading/working properly and does not have any wiring issues. For this test, you really need to have a scan tool that will graphically display engine parameters. ForScan on a laptop will do this (and of course the Ford IDS system will also).
My impression is that this type of erratic ICP reading would be seen more on the early style HPOP when it had failed (not so much the 05 and up). I am not 100% sure that this is a true statement though.
Repeat: One difficulty with this test is that a bad ICP sensor or connector can sometimes cause this type of saw-tooth behavior as well. That is why you have to be confident in their condition to begin with.
Back to leaks in the high pressure oil system:
A GOOD HPOP can have a leak at the bottom yellow (suction port) o-ring. This issue will cause behavior that will be similar to when the early HPOPs would blow out the suction side ball bearing (BB).
Most of the time, a leaking suction o-ring is due to improper installation (including installing the wrong o-ring in that position). If there has been no recent work on the HPOP, then I would not suspect an issue there, but as we know with the 6.0L .......ANYTHING can happen.
If the engine won't start "Nose High" (on an incline or "up slope"), but will start on a decline (down slope), then a suction side leak might be the cause.
SOMETIMES, a suction side leak on an HPOP can be bad enough to cause an issue with low base oil pressure (the Instrument Cluster gauge drops to zero). This will mainly happen with a big suction side leak (like the BB falling out of the HPOP). A high side leak RARELY acts this way, but sometimes a HUGE leak in the STC fitting might affect the dash oil pressure gauge.
Bulletin 19417 2003-2007 f-super duty/2003-2005 excursion 6.0l - watch for oil flow from the base engine oil pump:
EDIT:
An interesting video on swash plate pumps:
Potential CAUSES for HPOP failure.
It is possible that the HPOP can be damaged from insufficient flow of oil to it from the low pressure oil system. Many times we have seen/heard of HPOP failures AFTER someone has had low ICP issues because of using Ford filters with aftermarket (tall) oil filter caps. Badly leaking oil filter housing drain valves has also been a contributor to low oil flow TO the HPOP.
From this, two "take-aways":
I also wonder about excessively high oil temperature possibly playing a role in reducing the life of the HPOP. Just thinking out loud. I just hate running w/ excessively hot oil period. the EOT we see is the coldest point in the oil system (oil cooler outlet), so if it is high there, it will be quite a bit hotter at the HPOP discharge from heat of compression. Just something to think about.
Also - please note the following if you are going down the path of bench testing your HPOP:
.
Background information on the high pressure oil system (and note that the diagrams show the '05 and up system as identified by the style of HPOP):
To begin this thread, the video linked below is a good way to learn the system (but please note that DTR is not current in his saying that Standpipes are rare to fail. Now-days, they are probably the most frequent component to find failed). Also, in the video linked below, note that DTR mentioned that he had a bad OEM IPR right out of the box and it "kicked his butt" trying to do the repair. Lastly, please be aware, that due to the age of the 6.0L now, more and more issues w/ the '05 and up HPOP are being documented (still not common, but time and miles take their toll).
Also, here is a link to another thread I did on this topic:
Tests to verify a bad HPOP - Ford Truck Enthusiasts Forums
6.0L Power Stroke Diesel - Tests to verify a bad HPOP - One of the most common problem areas with the 6.0L engine is the high pressure oil system. (note this is a copy and paste of the thread I put together over on the Powerstroke.Org) Background information on the high pressure oil system (and...
www.ford-trucks.com
Leaks are common - especially with the late 04 and up oil rails (as mentioned earlier, sadly standpipe issues are FAR too common now), and the 05 and up (original) STC fitting. Even with no leaks, the IPR valve could have failed or be stuck open from debris ..... OR the HPOP could have failed.
This thread is not about identifying leaks however (I do mention a bit about more leaks later on, but it is not the focal point of the thread)! Instead it is about identifying a bad HPOP. Note that if the IPR valve is identified to be leaking, then remove it and look for debris on the IPR screen. If debris is found on the IPR screen, or inside the IPR valve, you need to identify this debris!! If it is metal, then identify what type of metal (if you can) is important.
If the IPR contains METAL debris (or has it on the screen, then this very well might be a sign of a failed or failing HPOP. If it is from the HPOP, typically the metal will be brass and non-magnetic (pay attention to the metal coloration). Early on Ford stated that slight amounts of metal on the IPR screen does not necessarily warrant HPOP replacement, but I lean to saying that even slight amounts would very likely justify replacement of the HPOP (regardless of year model or pump type).
With HPOP failures (very similar to leaks in the High-Pressure oil system), you will see a lack of engine power, AND high IPR commanded duty cycle (and often the actual ICP will be less than desired ICP).
From what I understand, the only "100% sure" way to identify a bad HPOP is to remove the pump and remove the cover and rotating assembly to inspect/test it. That said, if you open the pump you most likely make junk out of it. So, we need other ways to condemn the HPOP!
NOTE - the axial pumps were only used on the 7.3 and the '03 - '04 engines in the 6.0L. The '05 and up pumps were a "4V" style cam shaft operated piston pump that is more robust than the axial pump (thanks to @Hydro for this note).
The 03 and 04 HPOPs have a much higher failure rate than the 05 and up (cast iron) pumps. EVEN SO, the 05 and up HPOPs CAN AND DO fail occasionally!
Note that even though the late 04 engines had the change to the wavy oil rails (AND the HPOP capacity was increased slightly), the HPOP in that model year still had the weaker swash plate design. The HPOP "mechanical" design was not changed until the 05 model year and as such, the "failure prone" STC fitting was introduced in that model year also (unfortunately). The early model year (03-04) HPOP discharge piping DID have a type of snap-to-connect fitting, and it does fail occasionally. Ford came out with an updated "J Tube" that improved the reliability of this model year HPOP discharge fitting, and this updated part has been very reliable, a worthwhile upgrade! That said, the '03 and '04 J-tube failure (o-ring) was not the same as the failure prone 05 and up STC fitting). When people talk about a failed STC fitting on the HPOP discharge, they are referring to the 05 and up pump. When it fails, it can break apart with enough force to damage the rear cover, so it is something best done proactively IMO.
Enough about leaks for now!
Here is where I will happily send some compliments to CNCFab. Their upgraded aluminum (old style) HPOP has turned out to have a TREMENDOUS record for reliability. It and the DieselSite HPOP (Adrenaline) are the only two choices to consider if you are in a repair or if you want to upgrade the '03 or '04 HPOP proactively. The HPOP from CNC Fab is a better value and they have better customer service - hands down! For '05 and up HPOPs, I think OEM is still the best.
Pretty much everyone is aware of the air testing used to identify a leak in the High-Pressure oil system. The air test can be done two ways: from the ICP sensor port, OR from the IPR valve port. Typically, air testing SHOULD BE DONE before thoughts turn to an HPOP failure!! The best place to introduce air when suspecting a bad HPOP is from the IPR valve port (with the special test fitting). This eliminates ANY possibility of a bad IPR valve influencing the test results!
Identifying a bad HPOP is more difficult than finding a leak. In fact, a bad HPOP is TYPICALLY identified only after everything else in the High-Pressure oil system has been determined to be working as it should (ie low pressure oil pressure is sufficient AND NO LEAKS are present).
The most common method to identify a bad HPOP is when conducting the air test.
Note - if you have a leak in the high pressure oil rails, STC fitting, or even from an injector, it is best to repair these first, and then repeat the air test.
First remove the oil filter housing cap and then remove the oil filter. Then have someone hold down the oil filter housing drain valve, and introduce air into the high pressure oil system. The reason to hold down the oil filter housing drain valve is because sometimes "air sounds" from the crankcase can interfere with this test (say if air were to leak from other components like the standpipes). Holding down the oil filter housing drain valve keeps any air that might be in the crankcase from flowing into the oil filter housing.
Shop air at 150 psig - 175 psig air is recommended (there is no reason to go higher). When applying this air to the system, if air leakage OR a gurgling sounds are heard from the oil filter housing, then that means the air is most likely flowing backwards through the HPOP. This should not be possible w/ a healthy HPOP.
In addition, air flowing in reverse through the HPOP will also be able to be identified if air flows out of the turbo oil supply line (aerated oil will be expelled). Note that this is the turbo oil supply line, not the drain line!
Note that at least one HPOP supplier has stated that they do not want customers testing their HPOPs for reverse air flow when it has not been in service. The statement was that this might damage their HPOP. I don't know if this is true or not, but I would not recommend putting air into the discharge of a (newly received) remanufactured HPOP unless the supplier tells you it is OK!
Back to the testing process for identifying a bad HPOP (HPOP installed). Reverse flow of air when doing an air leak test is the common way documented to condemn an HPOP. I must say that this really needs a prerequisite mentioned:
Make sure you have oil in the low pressure oil system and that the HPOP is filled with oil. As mentioned above, you can get reverse flow of air when the HPOP is "dry" and this at a minimum would probably be a false positive result. Worst case, it might actually do some harm ton the HPOP. Anytime air testing (at pressure) is doe on the high pressure oil system, it is best to start with oil in the system.
The difficulty with interpreting this test is that air may not always flow backwards through a failed HPOP in every situation (HPOP internal position is a potential factor in the success of this test). It may leak in one orientation, but not in others. SO - if reverse flow of air is detected, it is most likely a failed HPOP. If reverse flow of air is not detected, then more testing is required.
In the case of no air detected with the HPOP installed in the engine, the next step is to bench test it (ie remove the HPOP and do the air test with it in a vise on the bench). When testing on a bench, the HPOP gear can be rotated to test for air leakage in all of the pump "internal positions". Sometimes when you try to slowly rotate it by hand, you might hit a "dead spot" with it (won't turn anymore). The HPOP is bad if this happens.
The second method to identify a bad HPOP is not as much of a "sure-thing" as the first ....... but it MIGHT BE easier.
NOTE - I read this on the forddoctorsdts.com web site, that site is an AMAZING resource! Thank you FordDoctor!
A bad HPOP will often times cause a repetitive fluctuation in the pressure of the High-Pressure oil (ICP pressure reading).
To detect this, you need to be confident that your ICP sensor is reading/working properly and does not have any wiring issues. For this test, you really need to have a scan tool that will graphically display engine parameters. ForScan on a laptop will do this (and of course the Ford IDS system will also).
- Connect up the scan tool. Set the tool to the graphical display mode.
- Watch the ICP pressure (and voltage) when cranking.
My impression is that this type of erratic ICP reading would be seen more on the early style HPOP when it had failed (not so much the 05 and up). I am not 100% sure that this is a true statement though.
Intermittent No Start
I am chasing an intermittent no start/ start stall on a 4/03. It may only happen once a week, but once the truck is started it will be fine for several days. Fuel pressure never seems to be an issue @ 54-55psi. Low oil PSi climbs as it should. I have several recordings, some times it looks as if ...
www.forddoctorsdts.com
Repeat: One difficulty with this test is that a bad ICP sensor or connector can sometimes cause this type of saw-tooth behavior as well. That is why you have to be confident in their condition to begin with.
Back to leaks in the high pressure oil system:
A GOOD HPOP can have a leak at the bottom yellow (suction port) o-ring. This issue will cause behavior that will be similar to when the early HPOPs would blow out the suction side ball bearing (BB).
Most of the time, a leaking suction o-ring is due to improper installation (including installing the wrong o-ring in that position). If there has been no recent work on the HPOP, then I would not suspect an issue there, but as we know with the 6.0L .......ANYTHING can happen.
If the engine won't start "Nose High" (on an incline or "up slope"), but will start on a decline (down slope), then a suction side leak might be the cause.
SOMETIMES, a suction side leak on an HPOP can be bad enough to cause an issue with low base oil pressure (the Instrument Cluster gauge drops to zero). This will mainly happen with a big suction side leak (like the BB falling out of the HPOP). A high side leak RARELY acts this way, but sometimes a HUGE leak in the STC fitting might affect the dash oil pressure gauge.
Bulletin 19417 2003-2007 f-super duty/2003-2005 excursion 6.0l - watch for oil flow from the base engine oil pump:
Some 2003-2007 f-super duty and 2003-2005 excursion vehicles equipped with a 6.0l diesel may exhibit low base engine oil pressure caused by a leak in the high pressure oil system. If a high pressure system leak is severe, the high pressure pump may use a larger volume of oil than the base engine (gerotor) pump can produce while cranking. If base engine oil pressure is low, remove oil filter, hold down the oil drain valve (left side of housing) with a screwdriver and crank the engine while watching for oil flow from the base engine oil pump. If flow is present, use the updated diagnostics for the high pressure oil system (electronic version of PC/ED manual, section 4, step 10e). If there is no flow at the oil filter housing diagnose the base engine oil system first (workshop manual section 303-01c). Effective date: 10/06/2006
EDIT:
An interesting video on swash plate pumps:
Potential CAUSES for HPOP failure.
It is possible that the HPOP can be damaged from insufficient flow of oil to it from the low pressure oil system. Many times we have seen/heard of HPOP failures AFTER someone has had low ICP issues because of using Ford filters with aftermarket (tall) oil filter caps. Badly leaking oil filter housing drain valves has also been a contributor to low oil flow TO the HPOP.
From this, two "take-aways":
- Make sure your low pressure oil system is healthy, and one element of this is to use OEM oil filters and an OEM oil filter cap!
- When changing the oil, take a look at the drain valve on the bottom of the oil filter housing (internal to the housing).
- When replacing your HPOP, after installation and before starting, pre-charging the system (priming) is always a good idea! Then, cranking for a short time (say 20-30 seconds) with the starter solenoid wire jumpered to the passenger battery (+) terminal would probably be a good practice. Probably would be good to repeat this cranking 3-4 times.
I also wonder about excessively high oil temperature possibly playing a role in reducing the life of the HPOP. Just thinking out loud. I just hate running w/ excessively hot oil period. the EOT we see is the coldest point in the oil system (oil cooler outlet), so if it is high there, it will be quite a bit hotter at the HPOP discharge from heat of compression. Just something to think about.
Also - please note the following if you are going down the path of bench testing your HPOP:
According to the Dieselsite folks, the front shaft seal isn't designed to be completely sealed. Trying to pressure it up w/ air with the intent of looking for a shaft seal leak is not appropriate! Air is so much less dense, and as such, air leaks are not indicative of pump problems at this point! Even a small oil leakage at the shaft seal (low pressure point in the pump) is not a big issue.
.
