I heard somewere that it hardened and cracked em. Who knows. Dont believe it my self. What i do know is i heard on powerstrokenation that black onyx head gaskets were junk. Sure nuff. I get two 6.0s pulled back in the shop due to gasket failure. Needless to say.....OEM for me all day,even on 700 plus HP trucks.

 

Slap a set of good cores in there and see if the problem resolves it's self.
If these things are all you work on, you should have an extra set around there some where right? If not, I just sold a core set for only $100. Half the cost of getting a se flowed. I know some guys don't keep stuff like that, but I do, just for situations like these.

I know this is a customers vehicle, but this might be the cheapest way of verifying if he's got a serious injector problem, rather than sending them out to be flowed.

Just my 2cents

 

I'm not entirely sure. Again Jim would be the guy to ask but I don't think flowing the injectors will tell you if there is oil bypassing the internal orings. Plus I was under the impression that any fuel inside the injector had to go into the cylinder. I'm no expert though and could be very wrong. Hopefully Jim will come along and straighten things out

 

The odd thing is that it is returning the fuel from the injectors in the fuel return (Filter is black) so it isn't just injecting the oil with the fuel, it is allowing it into the fuel rails in the head. Could a cracked injector cup allow that to happen?

Edit: I don't think it could (I'm answering my own question) since the injector cup just separates the injector from the water jacket. The passages for fuel and oil are actually cast into the head and the o-rings seal against the casting of the head for those passages.

 

Sleeves are not the issue here.
If the fuel filter is getting black from the oil, it has to be injectors.
If it's not from the external o-rings since you've replaced them, then it's the internals that are shot.
There are 2 different internal o-rings in each injector that hold high pressure oil back.
Example: When my guys here have a brain fart or are talking to their girlfriends on the phone when they should be paying attention to what they are doing, I can tell on the flow bench when one injector wasn't tightened all the way by the way it flows, and it fills my fuel tank (on the flow bench) with oil. The cause of this is the one o-ring between the injector bodies, same thing as when the o-ring wears away. The other o-ring seals the Intensifier Piston to the upper body. Both are rare to go bad, but like anything else they can and do wear out over time.

Your customer can be as cheap as he wants, but when you own these trucks you HAVE to be prepared financially to fix them properly.

And before anyone asks, no I don't sell internal o-rings so you can fix it cheap. There is no such thing as fixing the 7.3 injectors cheap and have them come out shining. If he doesn't want to pay to have them done properly, have him buy the parts on eBay and he can mess them up himself. I mean "fix" them himself.
The injectors need a complete Overhaul to do the job correctly.

Sorry if I sound bitter, but I deal with cheapos all the time.

 

Well there you have it, folks.

Just as we suspected... Thanks Jim.

I'd say if the OP's customer is too cheap to pay to have the sticks overhauled and fix it right, then his best bet is to find a set of usable cores to swap in.

 

Jim,you don't sound bitter. Its just the reality of cheapos. It sucks but sometimes it just is what it is.

Sounds like somebody is gonna have to spend some cashola.

 

Ohhhh there he is!.. yes,as above stated,ill put a spare set in. When i do narrow this down to the inj. I wont just replace 1 or 2. They tend to fail one after the other. Jim is the only guy i use for my 7.3 needs. If i can get him to budget build them. Then as usaul there commin to ya.
And confirmation is all i needed. They can leak internally. I new it! Thanx all 4 chiming in. I will report back.
Ohh yea,the diy kit jim sells is not for the weak of heart. So the 2 internalll o-rings he spoke of? No chance without the kno how and tools.

 

There you go. I didn't know that fuel could work its way from the inside of the injector back to the tank. Now I do lol. Good luck with the cheapo

 

The OBS trucks do have a sort of regulated return system. So High Pressure Oil blows past the o-rings into the fuel side of the injector since the oil is minimum 550 psi (or so) and the fuel is 55 psi (or so), the oil always wins.
Anyway, whatever fuel isn't used in the injection cycles goes back to the filter, hence the dark filter. And whatever fuel isn't re-used from the filter housing gets sent back to the tank. So you can literally dump 4 gallons of oil from the crankcase to the fuel tank and never know it till the truck stalls due to no High Pressure Oil.

 

But your apparent fuel economy will go way up.....

 

Ya, on the side of the road getting infinite mpg.

Good info Jim!

 

Thanks for the lesson Jim.

 

This is good info! My injectors have been leaking for some time (black filter) but not to this extent; maybe a quart every couple months. So I've been toying with the idea of just replacing the orings for ~$100; but if there are internal orings that can leak, I could just be wasting my money since rebuilds come with new orings and a budget build starts at $500. The weather has been super nice here lately and the Bronco is itching for some topless cruising, so think I see a budget build in my future!

 

If they have many miles you had better plan on premium builds. That's exactly what Jim will tell you. There parts that wear most of the time and you should plan on them all being bad. You might get lucky but he will tell you that MOST sets he sees need more than a budjet build.