dannyredfan

7.3 High pressure oil pump

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Well best I can tell my hpop has given up the gost . Started cranking long then not starting.  Then had to use eather .   Checked codes . Icp. Changed that (Motercraft)     and the other one (can't think of name) that reads oil psi. It was leaking but no code.   But tester says not meeting min psi.  Or something like that 

made a tester #5 oring boss to jic fitting  Hyd line and 5000 psi gauge it will only build <> 300 psi.       

Many ideas?

where is the best source for a pump?

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First of all, 300 PSI while cranking?

What year?

second, change the crank sensor before you spend money on a HPOP, it’s cheap and can give you all kinds of problems.  Do not use an aftermarket one.  Your leaking sensor has rebuild kits, I order parts from DieselOrings.com

 

 

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01 f350 

i put a Motercraft cam sensor in.  there was a code for it. 

Dont know about the oil psi. Sensor rebuild everyone said replace it. It is also Motercraft. 

Wher is crank sensor? 

From what I have been told it must hit 500 psi to fire injectors 

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Okay, if I can remember correctly the ICP and IPR are linked to the HPOP.  the system pumps the oil thru the head and into the injectors, if you loose (or slowly loose) an injector oring you will loose oil until you can no longer build enough pressure.

the cam sensor in on the passenger side of the front cover right next to the harmonic balancer, you need a 10 mm wrench

a couple things to ponder, is the HPOP still full? If you have a blown oring and loose oil you will not be able to build pressure, top it off and re-test if it’s empty and it may help you isolate your issue.

Is the truck full of oil and sitting level? Is the oil a decent brand? Non foaming and all?  

 

 

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Oh, one more thing, check your fuel filter, see if you have oil in the bottom, if certain o rings go the oil flows back into your filter.   It doesn’t mean it’s the only thing but it does eliminate one item

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Check fuse for heater in fuel bowl, if heater goes bad truck will blow fuse and not fire.

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 First.... Check glow plug relay. That is the first thing to look at when a 7.3 won't start and you use either. ( Don't please....) The wait to start light will still activate normally as it is controlled by an atmospheric sensor and times out correctly even though glow plugs are not actually working. Relay should make a pronounced click when you turn the key on. Try this, Short one or both relays (99-03's have 2) for 30 seconds or so ( think D282 glow plug button!) See if starts. You can amp test glow plugs, should draw nearly 150 amps. (!)

Check: Cam sensor as said IPR -Injector fuel pressure regulator and possibly your TPS, throttle position sensor. Although symptoms of TPS are; ok idle and little to no throttle response.  HPOP is a very rare problem on a 7.3, never replaced one and ran trucks that were close to 400K miles. Try "everything" before settling on HPOP as issue!

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I had low oil pressure for years on a turboed 7.3 not a power stroke. Turned out to be a gasket that was half plugging the hole in the return from turbocharger. It was worn out. And discover. The return was not letting oil back. I had a pool of oil on top of intake manifold.drilled the gasket larger. Poof i had good.oil pressure. Just a thought

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Just thinking out loud.

If injector o rings are bad they will leak by and the engine will burn oil, I don't think that will cause a starting problem.  

If the air temp is warm and glow plugs aren't working it should still start.

If cam sensor is out it will not start but should light the check engine light.

300 psi intensified by 7 gives you 2100 psi of fuel that should fire the engine.

I think the first thing I would do is get a scan tool hooked to the truck.

Best hpop pumps are the adrenaline pumps by Dieselsite.com

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Danny

         A couple of things to consider are:     A failed or inoperative Cam Position Sensor will not necessarily set a code, because for the sensor to not operate,  is a normal condition, ( this occurs when the engine is stopped).   These can be intermittent,  and will fail.   They have been updated by using gold terminals.   They are less expensive from your Navistar dealer.   

2 hours ago, jass1660 said:

Check fuse for heater in fuel bowl, if heater goes bad truck will blow fuse and not fire.

Jass has a correct statement.   Both of these have happened to me.

3 hours ago, AKwelder said:

Okay, if I can remember correctly the ICP and IPR are linked to the HPOP.  the system pumps the oil thru the head and into the injectors, if you loose (or slowly loose) an injector oring you will loose oil until you can no longer build enough pressure.

the cam sensor in on the passenger side of the front cover right next to the harmonic balancer, you need a 10 mm wrench

AK is also right.   You can check the injectors  ( for leaking high pressure oil, by removing the valve covers and checking for oil leaking around the injectors while cranking the engine ).

         I am not sure about what I'm getting ready to say, but I think that this engine High Pressure Oil Pump will vary the high pressure depending on how much fuel has to be injected.   I think that this is the purpose of the Injection Pressure Regulator.    If I am wrong, I hope someone will correct me,   I' m going on memory and don't have my manuals in front of me. 

Fred

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I have had the same situation with my 2001 F350 about 10 years ago. Acted just as you have described. Turned out to be the crank sensor. I would try to replace that

 

Erich

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You could always convert it to mechanical...

CE74CF0F-FD22-465D-94E2-937281A0BD6B.jpeg

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Years ago, work truck (1997) died and would not restart. Internet said if the tach worked cranking it was not CPS. I tested high pressure oil 300 to 350 psi cranking. Turned out internet lied, CPS was bad changed and started right up. 4 months before recall.

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2 hours ago, chip man said:

Years ago, work truck (1997) died and would not restart. Internet said if the tach worked cranking it was not CPS. I tested high pressure oil 300 to 350 psi cranking. Turned out internet lied, CPS was bad changed and started right up. 4 months before recall.

Think I went thru 3 CPS in my '96 before the recall.  First one around 50,000 miles covered by warrantee. Then two more while it was still my daily driver. 50,000 to 70,000 miles is about all the longer mine have lasted. 302,000 on it right now.

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3 hours ago, jass1660 said:

You could always convert it to mechanical...

CE74CF0F-FD22-465D-94E2-937281A0BD6B.jpeg

You really piqued my interest, until I looked it up and saw the $11,900 price tag for that conversion!

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53 minutes ago, RBootsMI said:

You really piqued my interest, until I looked it up and saw the $11,900 price tag for that conversion!

But how many 700 HP 7.3 PSD's are there running around? 

 

Parts Dept. of the dealer I bought my '96 7.3 PSD F250 from had an early 7.3 PSD, a 94-1/2 sitting on the shipping skid right inside the door for a year.  You get rid of all the front engine dress, it's really a compact engine.

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I have never worked on the 7.3 PSD, but the fuel system is closely related to the Cat 3126 that I have worked on many. Some of what I know may cross over.

Assuming all electronic wiring is OK.... look over harnesses and connections, check your grounds and check your grounds again.

On the Cat, there is a solenoid valve that controls actuation pressure, if it goes out or bleeds pressure, low actuation psi results, that is problem #1. 

Next is as stated above, injector o-rings. The actuation pressure is lost back to crankcase or into your fuel. #2 in likely.

Are you certain the fuel is not bleeding back to tank or that you don't have an air leak in the fuel supply. If there is air in your fuel, the injectors won't create resistance to the actuation oil and it won't create pressure.

Failed HEUI pump not making pressure.

Totally failed injector leaking Heui pressure.

Timing reference, cheaper to fix but less likely than above. 

ECM, this was unlikely in the past, but is becoming more common.

Proper HEUI fuel system troubleshooting needs a gauge on the supply fuel pressure, the supply oil pressure, the HEUI actuation pressure, and a scan tool hooked to the ECM. You have to compare mechanical readings to those indicated electronically before throwing parts at it.

 

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Need a fuel psi tester .

 Where is the crank sensor?

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14 hours ago, dannyredfan said:

Need a fuel psi tester .

 Where is the crank sensor?

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15 hours ago, dannyredfan said:

Need a fuel psi tester .

 Where is the crank sensor?

It’s a cam position sensor not crank sensor. 

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And it is held in with a clip on connector , you need a 10MM wrench and a smallish screwdriver/pry bar to ease it out.

You said in the first post you used either, I am assuming that it was still a no start.

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1 hour ago, TomH said:

You said in the first post you used either, I am assuming that it was still a no start.

If the engine fired and died with ether I would suspect no fuel (supply or injector actuation faults). If it fired and ran I would suspect glow plug failure.

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Glowshift gauges have a high pressure electronic gauge for a good price.  If it is a reliable as their gas fuel pressure gauges it is a keeper.

 

 

 

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