7.3 High Pressure Oil Pump Leak HPOP

Fixing a 7.3 High Pressure Oil Pump Leak


The dreaded 7.3 high pressure oil pump leak is probably the most common oil leak that your 7.3 Powerstroke can get.

Picture this... You're motoring down the highway, enjoying the deep growl of your diesel engine, when suddenly you lose power, lose oil pressure, and chug-chug your way to the shoulder. When you get out, there's oil dripping down onto the side of the road, right beneath the rear of your engine. You might think it's a rear main seal leak, but chances are high you have a 7.3 HPOP leak.

7.3 HPOP Leak Basics

A Ford 7.3 Powerstroke high pressure oil pump leak is arguably the most serious of the oil leaks that your diesel engine can get. This is due to the tremendous amount of pressure that the HPOP puts on its components — 500psi at idle and up to 3000psi under heavy throttle. Even a small HPOP oil leak can become serious rather quickly.

Because when an o-ring in one of the 7.3's high pressure oil pump fittings, the rear drain plug o-ring, or the "non-serviceable" plug o-ring finally fails, a 7.3 HPOP leak that's gone unnoticed as a trickle will quickly become a fountain.

So be careful...

Because any of the 7.3 Powerstroke common oil leaks on top of the engine spill out the drain hole at the rear of the valley. Then they go down around the bell housing and drip right down the back of the engine.

In fact, all the top end — "valley" — oil leaks on the 7.3 engine flow by or next to the high pressure oil pump. Which is why a bad HPOP leak is often misdiagnosed as a 7.3 rear main seal leak.

Always check your engine valley for oil first. Look in the front of the valley just after the HPOP and before the turbo pedestal.

Here's a comprehensive guide to spotting and fixing the 7.3 Powerstroke high pressure oil pump leak.

7.3 HPOP Leak Symptoms Pressure Gauge

7.3 HPOP Leak Symptoms

When it comes to 7.3 Powerstroke high pressure oil pump problems, there are seven main symptoms to look out for.

HPOP Leak Symptom #1 - Oil in Your Valley

It's a good idea to frequently check the 7.3 engine valley — the area on top of the motor between the cylinder heads — for leaks.

Simply put, a lot of oil in the engine valley in a short amount of time points to the exhaust back pressure valve (EBPV), one of the HPOP fittings, the HPOP rear drain plug, or the 7.3 Injection Pressure Regulator (IPR) o-ring.

If you do find an accumulation of oil in the engine valley, you can pinpoint a 7.3 Powerstroke HPOP oil leak by:

  • Fully cleaning the valley with paper towels or shop rags
  • If you have to, get a slow and low flowing garden hose to clean the valley
  • Sop up all the excess oil and water with paper towels or rags
  • Thoroughly wipe off the fittings where they connect to the HPOP
  • Next, start your truck and run it for a bit—rev it a little, maybe
  • Then inspect the fittings and the rest of the HPOP with a good flashlight.

If there's any fresh oil around the HPOP fittings, HPOP drain plug or your IPR, you've found your leak.

HPOP Leak Symptom #2 - P1211 code

The two most common codes associated with an HPOP problem are P1211 and P1212 — IPR above/below normal.

A 7.3 Powerstroke P1211 code could be caused by a couple things.

A leaking 7.3 IPR o-ring can cause a P1211

The IPR is screwed into the bottom right rear of the 7.3 HPOP. The IPR's job is to regulate the amount of pressure going to the injectors.

The high pressure pump can produce pressures in excess of 3,000psi.

The IPR operates on pulsed voltage. And the amount of IPR on time versus off time is called the “duty cycle.” And the IPR can regulate 3,000psi with no more than 12% duty cycle.

There's more...

The 7.3 PCM (Power-train Control Module) is capable of providing up to 60% duty cycle to the IPR. However, once it reaches 50%, the PCM sets a trouble code P1211 or P1212 for ICP (Injection Control Pressure) above/below normal.

All that complicated explanation can mean a couple of things:

  1. Your HPOP is malfunctioning (leaking)
  2. Or your 7.3 IPR is bad or leaking.

A Leaking ICP can also Cause a P1211

Though the 7.3 ICP (injection control pressure) sensor isn't technically part of the 7.3 HPOP, it is one of the high pressure oil system's major components. So it's worth mentioning here.

Because a bad or leaking ICP can cause a P1211 code as well.

As always, first check for leaks in the engine valley, underneath the IPR. If there's nothing there, then unplug your ICP pigtail and inspect it for oil. If there's any oil in the ICP or pigtail, replace the ICP and the pigtail.

Here's the tough part about a P1211:

A slow-leaking HPOP won't necessarily throw a Check Engine Light — CEL. Or cause noticeable drivability problems until enough oil is lost to reduce flow to the injectors.

So, by the time you get a P1211 CEL, you're about to start walking.

Here's why:

The 7.3 diesel engine expects to see around 500psi of HPOP oil pressure at idle. If it doesn't, it won't fire the injectors.

No oil pressure from the HPOP means no injector pressure. and without injectors you're dead in the water.

HPOP Leak Symptom #3 - HPOP Reservoir Low Oil Level

You can check for slow oil leaks from the 7.3 HPOP by measuring the HPOP reservoir level (With the engine OFF!)

The reservoir should have oil all the way up to 3/4 to one inch from the top of the inspection plug port.

There's a check valve that prevents oil from draining back out of the HPOP reservoir. So if your 7.3 HPOP reservoir's draining it'll have less oil than it should.

You can use a flashlight, but I check my HPOP oil level with a long metal BBQ skewer inserted gently into the reservoir. It's as good as an oil dipstick.

HPOP Leak Symptom #4 - Low Oil Pressure

If your injection control pressure reading is under 2600 - 2800psi, you may have an HPOP leak.

Once again, check for oil in your 7.3 engine valley. Also, use a good flashlight and inspect all seven common HPOP leak locations we've listed here.

Look for any fresh oil near a fitting, plug, the rear plate or he IPR.

HPOP Leak Symptom #5 - Hard Start When Hot

When oil is cold it's thicker and thus less likely to escape through a minor leak.

So if your 7.3 HPOP starts hard after it's been warmed up, you may have a slow oil leak in your high pressure oil pump.

With the HPOP buried underneath the fuel bowl, checking for oil leaks is tough. However, you can get a mini mirror on a magnetic pointer and check around each of the seven common HPOP leak locations below.

HPOP Leak Symptom #6 - Poor 7.3 MPG

If you experience a sudden drop in your 7.3 Powerstroke MPG or your truck starts to idle or accelerate poorly, your HPOP may have a leak.

Lower oil pressure will cause your 7.3's injectors to have trouble delivering enough fuel.

In addition, as the injectors become starved for fuel due to low oil pressure, a 7.3 HPOP leak will cause chugging, missing, or rough running, 

HPOP Leak Symptom #7 - Tailpipe Smoke

There's nothing like smoke coming out of your 7.3 exhaust tube to tell you that fuel isn't being burned up in combustion.

The oil volume and pressure from the HPOP actuates the injectors. If they aren't operating efficiently, then excess fuel is leaving through the tailpipe as black or white smoke.

Well, now that we've covered what to look for, here's where to look to determine if your high pressure oil pump has a leak.

7 Most Common 7.3 HPOP Oil Leak Locations

Depending on how you count them, there are 7-8 leak locations on the 7.3 Powerstroke HPOP.

Here's a diagram of the first four 7.3 HPOP leak locations:

7.3 Powerstroke High Pressure Oil Pump Diagram

7.3 HPOP Diagram

Leak Location #1 - 7.3 Oil Line Fittings

Arguably the most common 7.3 Powerstroke HPOP leak happens when one or both of the o-rings on a high pressure oil line fitting fails.

The HPOP line fitting o-rings are a well-known failure point and cause for a leaking HPOP. Do yourself a favor and if you see even a little oil leaking around them, perform some preventative maintenance.

Change the o-rings before they fail and dump your 7.3's oil into the engine valley.

The HPOP oil lines click into the snap to connect (STC) fittings on the 7.3 high pressure oil pump and the cylinder heads. They require a special, 7.3 high pressure oil line tool to disconnect the lines.

If you've eliminated leaking HPOP fittings, move on to...

Leak Location #2 - Rear Drain (End) Plug

Sometimes the drain plug on the rear of the HPOP leaks. Ford calls it the "end plug."

Run your fingers around the head of the plug and check to see if there's fresh oil. Even if you only find a small amount, don't take chances — a preventative o-ring change on an HPOP rear drain plug leak will save you a walk home.

Leak Location #3 - IPR O-ring

The 7.3 IPR is sealed to the HPOP with an o-ring.

So if you have oil leaking into the valley from the bottom right rear of your 7.3 high pressure oil pump, it's a safe bet that the IPR o-ring is the cause.

If those three 7.3 HPOP leak locations aren't the source of your oil leak, check these next...

Leak Location #4 - "Non-serviceable" Plug

Though the "non-serviceable plug" (See location in diagram above) is a very uncommon leak, it can and does happen.

DISCLAIMER: There's a Ford TSB floating around somewhere that states you will damage your HPOP if you remove the non-serviceable plug. So DO SO AT YOUR OWN RISK.

But here's the bottom line...

If you do decide to perform this maintenance yourself, the procedure requires fuel bowl and HPOP removal before you can replace it.

Removing the fuel bowl and the HPOP are non-trivial, so it's a good idea to eliminate everything else on the HPOP before you decide that the non-serviceable plug is the source of your leak.

The reality?

When removing/replacing the 7.3 HPOP non-serviceable plug, pay attention to the details in the instructions. Because there's a little check ball in it that has to be put back in correctly or your HPOP won't work.

Leak Location #5 - Rear Pump Plate O-ring

A leaking or weeping o-ring at the HPOP rear plate (See diagram below) is very uncommon. Look to this location after you've inspected the HPOP fittings, the rear drain plug, the IPR and/or the "non-serviceable" plug.

7.3 Powerstroke High Pressure Oil Pump Diagram - Rear Swash Plate

7.3 HPOP Rear Swash Plate Cover Diagram

The HPOP will have to be removed from the engine in order to do the delicate work of reinstalling the c-clip in front of a leaking rear plate o-ring.

Combine this with the fact that on 1999-2003 HPOPs the 7.3 fuel bowl needs to be removed to make HPOP removal easier, and you'll see why you need to eliminate all other possibilities first.

Leak Location #6 - HPOP Reservoir Gasket

7.3 oil leaks at the HPOP gaskets are also pretty uncommon.

There's one gasket between the HPOP reservoir and the HPOP reservoir top cap — the "Reservoir Gasket."

7.3 HPOP Diagram of Reservoir Gasket

7.3 HPOP Diagram - Reservoir Top Gasket

Here's what the 7.3 HPOP reservoir gasket looks like with the filter screen.

7.3 HPOP Reservoir Gasket Part Number - YC3Z-6619-BA (eBay link)

7.3 HPOP Reservoir Gasket

The second HPOP gasket is the mounting gasket between the pump and front engine cover.

7.3 High Pressure Oil Pump Mounting Gasket Diagram

If your HPOP Leak is due to a failure in this mounting gasket, you'll have to remove the fuel bowl and the HPOP to replace this gasket.

See 7.3 HPOP Removal Instructions for details on how to do that.

Here's what the actual part looks like:

7.3 HPOP Mounting Gasket

Leak Location #7 - HPOP Reservoir Plug "leak"

This isn't so much of a leak as it is a maintenance mistake.

For you 7.3 HPOP oil changers out there. (I admit it — I'm guilty) And/or after you've manually pumped the oil out of the HPOP in order to perform repairs or remove the HPOP...

Don't forget to put the inspection port plug (on top of the HPOP reservoir) back into the top of the HPOP reservoir cap ... before starting your truck and revving the engine.

7.3 HPOP Reservoir Inspection Port Plug Diagram

Because that will cause copious amounts of oil to spray from the top of the HPOP into every nook and cranny under the hood before you get your engine shut down.

When you peek under the hood, your "leak" will look like Old Faithful sprayed oil all over everything inside your 7.3's engine compartment.

Tools, Parts, and Torque:

Okay, now that we've pinpointed our 7.3 high pressure oil pump leak, let's fix it.

Adrenaline HPOP 7.3 Powerstroke Review

7.3 Adrenaline HPOP

Adrenaline HPOP 7.3 Powerstroke Review

7.3 Adrenaline HPOP

Repairing a Ford 7.3 High Pressure Oil Pump Leak

To fix many of those seven HPOP leaks, you'll have to remove the HPOP.

But here's the thing:

7.3 HPOP removal is much easier once you remove the 7.3 fuel bowl.

7.3 Fuel Bowl Removal

Removing the fuel bowl on a 7.3 is basically disconnecting four fuel lines, a drain hose, and the fuel bowl heater electrical connection.

Sometimes it's just easier to show rather than tell how to do something. I found this great video on 7.3 Fuel Bowl removal.

After about 2:50 on the video clock, it also goes into detail on removing the 7.3 fuel lines and then resealing the fuel bowl.

That's beyond what we need to do to get at the 7.3 HPOP to remove it, but still some great info.

Now that we can actually see the 7.3 HPOP...

7.3 HPOP Removal

To get at the HPOP rear plate seal, the HPOP non-serviceable plug, or the HPOP mounting gasket, you'll have to start with HPOP removal.

I'd argue that replacing the fittings, rear drain plug, and/or IPR o-ring would be easier with the pump out of the engine as well. Oh, you can get to them, but they aren't going come out without a fight and some bloody knuckles.

Removing the fuel bowl means you'll need to order a fuel line reseal kit (eBAY LINK). It comes with 4 - 1/4", 1 - 3/8", and 1 - 5/16" hard line sleeves that seal the fuel lines to the fuel bowl. These sleeves are crush sleeves and aren't reusable.

You only need two of the 1/4" sleeves to reseal the fuel bowl. The other two 1/4" sleeves are to reseal the other ends of the 1/4" fuel lines. If you don't plan on removing the fuel lines from the cylinder heads, they're "extra" sleeves.

7.3 HPOP Leak Repair - Fitting and Drain Plug Reseal

The most common HPOP leak (O-rings in the oil line fittings leaking) aren't the most difficult in the world to repair.

My suggestion — buy new 7.3 HPOP fittings (eBAY LINK). You'll see why in the video below.

FordTechMakuloco has a great YouTube video on 7.3 high pressure oil pump leak fitting repair. (See video below)

That video shows draining the HPOP by removing the rear drain plug and letting the oil run into the valley. But I'd suggest pumping the oil out of the HPOP reservoir first by using a cheap fluid pump (AMAZON LINK).

Less messy that way...

I've also seen people use the pump from a lotion or soap dispenser to pump about 1 quart of oil from the HPOP reservoir.

Then remove the drain plug, clean up any excess oil that drains out, and replace the drain plug O-ring and reinstall.

Tools, Parts, and Torque:

  • 7.3 high pressure oil line tool to disconnect the oil lines from the fittings.
  • 3/16" Allen wrench and a handheld fluid transfer pump to remove the quart of oil from the HPOP Reservoir. Torque — I wasn't able to find torque specs on the Reservoir Plug. So I'd snug it but not over-tighten it. (You want to avoid damaging the little o-ring on the plug)
  • A 19mm socket with an extension to remove and replace the fittings. A swivel head adapter will let you get at the rear one a little easier.
  • New 7.3 HPOP Fittings — f81Z-9C402-AA — Torque to 25 ft. lbs. (Drain plug is 25 ft. lbs. also)
  • New O-rings for the fittings and drain plug — 2C3Z-9G804-AB (Amazon link)
  • Loctite 680 to reseal the oil line fittings to the HPOP. (A small tube of this come in the HPOP o-ring reseal kit above)

I'd suggest pumping the oil out of the HPOP reservoir first by using a cheap fuel transfer pump.

Then remove the drain plug, clean up any excess oil that drains out, and replace the drain plug O-ring and reinstall.

7.3 HPOP Leak Repair - Non-serviceable Plug

To replace the non-serviceable plug with a serviceable plug, you'll have to remove the HPOP from the engine. Otherwise, the plug can't be removed and you'd probably lose the little check ball even if the plug would come out.

Tools, Parts, and Torque:

Here's Diesel O-ring's comprehensive guide on how to service and replace the non-serviceable plug on the 7.3 HPOP.

7.3 HPOP Leak Repair - IPR O-ring

The IPR-Injection Pressure Regulator is screwed into the back of the high pressure oil pump. It's seated and sealed with an o-ring.

And as long as you have to remove the IPR to replace that o-ring, you might as well clean it, and then rebuild and reseal it.

Here's what comes in the 7.3 Powerstroke IPR valve rebuild kit (AMAZON LINK)(IPR not included):

7.3 Powerstroke IPR Valve Leak Rebuild Kit

Tools, Parts, and Torque:

7.3 IPR removal / replacement (leaving the HPOP in the truck):

  • Remove negative terminal cables from both batteries
  • Flip the wire bail on the IPR electrical connector
  • Unplug the electrical connection to the IPR
  • Remove the Tinnerman nut on the end of the IPR
  • Slide the IPR spacer off the IPR body
  • Slide the IPR solenoid off the IPR body
  • Then use a 1 1/8" deep-well socket to remove the IPR from the HPOP
  • Install 7.3 Powerstroke IPR valve rebuild kit
  • Reinstall the reassembled IPR body into the IPR port on the HPOP - (Torque - 37 ft. lbs.)
  • Slide the 7.3 IPR solenoid onto the IPR
  • Then the IPR spacer
  • Then screw on the Tinnerman nut on the end of the IPR - (Torque - 49 inch. lbs.)
  • Reattach IPR electrical connector and close wire retaining bail

7.3 HPOP Leak Repair - Rear Pump Plate O-ring

Above, we mentioned the rear swashplate cover o-ring leaking.

This is a delicate repair and is probably best left to professionals. However, if you're a serious DIY mechanic and you have the patience, here's what you'll need.

Once again, the HPOP and fuel bowl will have to be removed from the engine in order to do the delicate work of reinstalling the c-clip in front of a leaking rear plate o-ring.

Tools, Parts, and Torque:

  • It takes a set of 8" c-ring pliers to properly reinstall the c-clip without cutting the o-ring or misaligning the rear plate in front of it.
  • You can get the rear plate o-ring at Riffraff Diesel. They also have instructions on the process to successfully install the o-ring without damaging it during reinstall.

7.3 HPOP Leak Next Steps

Here's the article on 7.3 HPOP Removal and Replacement. It goes into detail on how to remove and reinstall the 7.3 HPOP and the 7.3 fuel bowl.

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