[250lifer]

My 1995 7.3 diesel left me when I needed it most.

I don't drive it very often so it sits in storage most of the time. It has about 190,000 miles on it
and had not been smoking any oil other than the fuel. It has no oil leaks. I never have to add oil between
oil changes.

So I checked the oil a few months back and saw it was over a quart low. The disappointed me because it was
the first time I saw any drop in oil level. So I drove it about 30 miles and then parked it again without checking the oil.
So I checked it again before planning a 1,400 mile move my household trip. This time no oil appeared on the dip stick.
Now I am astonished because this is a massive oil loss that I had not seen any evidence of. Had not been watching the tailpipe for smoke. But here is the punch line: I added over 2 gallons of oil to reach full mark. I look under the truck for an oil lake and don't see anything. I start to look carefully at the exhaust pipe and I do see blue smoke at idle and a fair amount puffing once I press the throttle. I do not see white smoke like I see other posts describing.

So here it is in one sentence : all of a sudden its using over 2 gallons of oil in a distance of 30-40 miles and its certainly be burned.

I am looking for tips on how to determine the source. I see it could be a turbo seal issue or possibly fuel injector seals.

Totally stock setup, no recent maintenance to the fuel or air systems. I did need extensive brake system maintenance though, new master cylinder, new booster chamber and new engine driven vacuum pump.

Again. nothing found dripped into concrete garage floor.

 

[bugman]

Take a look at your fuel filter and see if it is black. If it is you need new injector O rings

 

[Patrick Feeley]

My 94 used no oil in between 5k changes. I forget the mileage I was at at the time, but I think it was maybe 175k. I had just changed the oil and I used 8 quarts in 150 miles. No smoke out the exhaustDrained some fuel from the filter bowl (current fuel tank was at about 1/4) into a glass jar. You couldn't see the sun through it! It looked like, well, used motor oil. Changed all the injector o-rings (use Ford/International/Alliant only ... Diesel O-Rings.com or Riff Raff sell them) and back to normal. A note: They changed the o-ring set design to not use a backup ring like the early trucks used. I'll have to look and see if I can find the document that had that info. Cheers!

 

[klhansen]

Agree that the issue is injector o-rings.

The design of the ring between fuel and oil galleries changed design. I don't recall if there were two rings in that groove or not, but now it's a single piece with kind of a double keyhole profile. The top o-rings still use a steel backup ring, and an issue there is the sharp edges of the ring. If you take a fine file or stone and knock the corners off, that will help the ring next to the steel backer from getting cut there.

[on edit] Here's a pic of the old style o-rings with two rings between the fuel and oil galleries. It was changed to a single ring design. You can also see where the upper o-rings were cut by that steel backer. My issue wasn't oil loss on this one, but loss of HP oil pressure getting out thru that (those) top o-rings and back to the oil pan.
Link

 

[ArcticDriver]

Great Photos.

 

[Oneof6]

Those that have a DAHL Filter can just look at their water separation section and tell, its something I do to check for water and fuel discoloration.

 

[DENNY]

I would agree with bugman. Do a search, lots of good posts on how to do it and what ones to use. Replace the wiring harness under the valve cover while you are there. It is about an 8 hr job by yourself give or take. DENNY

 

[bugman]

I'd also do the glow plugs since you are in there, plus with them out you can clean out any oil that gets into the cylinders

 

[Patrick Feeley]

Here's a picture of the change to the injector o-ring kit. Cheers!

 

[Steve83]

Where is the engine SN?

 

[bugman]

If you can still read it there was a paper one on the front of the HPOP.

If not then it is stamped into a machined area of the block above the oil filter, or right close to that area.

 

[DENNY]

Pay close attention to the rear valve cover bolt on the passengers side as you take it out. That one always seems to be the hard one to put back in go slow and make sure you don't cross thread in going back in. The heads are the same just reversed so if you are having issues look at the front of the drivers side. DENNY

 

[Patrick Feeley]

On my 97, there is a sticker on the HPOP reservoir with "444023" in fairly large numbers and a barcode below them. That is my engine serial number. On most trucks, the sticker is long gone. Stamped into the block on a machined surface just aft of where the oil filter/oil cooler header bolts to the block is "74J U2U 444023 *" which ignoring the 74J U2U and * (or punch mark, whatever it is) leaves the "444023". I had to scotchbrite the area clean and use a flashlight at the correct angle to be able to read it.

Cheers!

 

[klhansen]

You don't need to worry about the engine serial number for injector o-ring replacement. All the sets you can buy will have the updated o-rings. If you were to cut the oil-to-fuel o-ring the profile would look something like this: <O>.

 

[Steve83]

If you can still read it there was a paper one on the front of the HPOP.
If not then it is stamped...

...on a machined surface just aft of where the oil filter/oil cooler header bolts to the block...

Thanks to both of you. This is what I found:

You don't need to worry about the engine serial number for injector o-ring replacement.

I was more concerned whether I NEED to replace them, rather than which ones to get. Based on the image Patrick posted above, I need to at least order them, even if I wait until there's a problem before actually replacing them. I want to have them in the truck, even if they're not in the engine yet.

Now that I want them, I'm going to look for the updated kit.

Changed all the injector o-rings (use Ford/International/Alliant only ... Diesel O-Rings.com or Riff Raff sell them...

The parts list thread says (Ford) XC3Z-9229-AA or XC3Z-9229-AB
(International) 1833564C91

But this ebay listing shows the -AA Ford PN (which appears to service 1 injector) with the backup O-ring configuration:

Ford Xc3z-9229-aa Injector Seal Kit | eBay

Ford Xc3z-9229-aa Injector Seal Kit. Condition is New. Shipped with USPS Parcel Select Ground.

www.ebay.com

This -AB looks the same (MotorCraft PN CM-5010):

Amazon.com: CM-5010 (Set of 8) New OEM 7.3L Diesel Fuel Injector O-Ring Kits: Automotive

Buy CM-5010 (Set of 8) New OEM 7.3L Diesel Fuel Injector O-Ring Kits: Fuel Injectors - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

This International package looks the same to me:

INTERNATIONAL Injector Seal Kit 1833564C91 NEW IN packaging OEM | eBay

FREE SHIPPING! Usually ships same day.<br><br>Brand New International Injector Seal Kit <br><br>Part # 1833564C91<br><br>Please make sure this is the correct item you are bidding on. <br><br>Please note that this is a brand new set never used. Some bags had a small opening or a tear but were...

www.ebay.com

Same again with the Alliant set:

Alliant Injector O-rings

Alliant Injector O-rings Ford Powerstroke 7.3L Fuel Injector 1994-2003

www.riffraffdiesel.com

...from DOR, too:

Exterior HEUI Injector Seal Kit for the 1994.5-2003 7.3L diesel.

Alliant Exterior HEUI Injector O-ring Seal Kit for the Ford 1994.5-2003 7.3L diesel.

www.dieselorings.com

None of them look like Patrick's pic above, or klhansen's description. Am I looking up the wrong ones? If those are right - are the $8/injector Alliants as good as the $12/injector Internationals, or the $12/injector MotorCrafts?

 

[bugman]

I'd stay away from Ebay and Amazon and order them from RiffRaft or Diesel O Rings.

Just to have a better chance of getting genuine Alignt O rings

Sent from my SM-J737V using Tapatalk

 

[Patrick Feeley]

Steve83, In the Aliant pic you posted, the Pink O-ring is the new style. They used to use 2 o-rings in that middle groove and now only one (and as mentioned by klhansen, the cross-section shape is different). The top groove still uses 2 o-rings and the metal ring. The old parts list thread may be out of date. The latest number I have is XC3Z-9229-AB. Cheers!

 

[Steve83]

Well, they all have the pink O-ring, so it sounds like they're all the correct new design. I prefer & trust parts sealed in original branded packaging, and the cheaper ones from DOR & RR don't show any, so I'm leaning toward the Int'l parts. The MCs are only a pennies more per injector. But I've got some time to decide since nothing will be delivered for a week or more anyway. How do the ones from DOR & RR arrive? Loose, or sealed & branded?

 

[ArcticDriver]

These projects that require alot of labor are worth buying Motorcraft, IMO.

 

[Patrick Feeley]

The Aliant ones I got from DOR or RR (I can't remember where I got them) were in sealed packages for each injector. Kits from Ford (online) are $11.62 each (Autonation Ford White Bear Lake). Cheers!