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Injector O ring Blowning 2 times

17765 Views 19 Replies 10 Participants Last post by  sd528
Hello guys,
I'm new to the forums so please bear with me. I have a reaccouring oring on my number 5 injector that keeps blowing. Its the lower fuel oring and it blows after about 300 miles of perfect, no problem starting/driving. There are no symtoms till it accually happens. Both times it has blown I was driving at 70 mph on the hwyway without a load. It blows and then white smoke and it then shutters and dies. Starting it back up is very hard and then it will die becasue of hydrolock and will not turn over again. Apon inspection the lower oring is blown and the cylinder is full of fuel. Last time dealer replaced oring and re torqued to specs. All numbers are good on the CTS monitor. SCT tune was on performance at both times of malfunction. I just had major work performed on my truck, its listed below in the specs. Thanks for any help you may offer I'm stumped and this is getting expensive.

Some specs of my truck
06 F350 CC SB FX4 Lariat; 79K on truck, new in the last 1000 miles: ARP studs; new OEM gaskets; heads redone w/ hardened seats, MBRP turbo back, cat delete exhaust; IPR screen upgrade, Coolant filter; Fumoto valve, Blue FPR spring; BulletProof EGR cooler, OIL cooler and Oil bypass filter, BilletWater Pump, 6.4 Banjo bolt upgrade, new glow plugs, 5w40 rotetilla syn, Sinister coolent bypass, FICM checked 48.5-49v, SCT X3, CTS Edge Monitor, EGT Probe, All new oil/fuel and tranny filters. I may have forgot somethings. Please help!!
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Copper washer on injector bad and combustion gasses are trashing the o-ring. Maybe a problem with the injector sleeve. I would say all new injector seals ETC and then get a tube cleaning brush and scrub the injector sleeve until it shines. By now there may be a ton of carbon in there causing the repeat failure. IF you can get a look down there with a bore scope that might shead some light on the situation.

MY best guess.
THanks

Wow thanks for the fast reply. Question? Is the Injector sleeve and the cup the same thing or?? Thanks for the info I really appreciate it. Dom
Yes,I think they are, I get korn-fused on my terms sometimes, Good luck
Also don't forget to clean out the bolt threads for the injector hold downs. Oil and dirt can prevent you from torquing down.
Injector cups=injector sleeves.

If they are the front 4 cylinders you can do them in cab with the ford installer/remover.

If they are the back 4 cylinders youll need the whittaker cup tool. And its not cheap. I know i have one.
Bill, nice box
Thanks man! Wana buy it? Its full allready, i need a bigger one. Thinking about either the larger macsimizer or the new one with power the MB 7432. Has bigger drawers and you can put an IDS in a drawer thats for the laptop. Its perfect. Or i could just stitch a couple side cabs on it and be fine but i really like this new one.

I wanted to put a hutch on it with the stereo. The stainless steel top is awesome i clean turbos and assemble/disasemble 6.4 turbos on. Its stouter than the snap on boxes by far. No plastic lock tabs, has detents in it so the drawers can pull out easy or feel like theyre locked.
They only come in black and green but i hated the way they look with black and green. i made the mac guy pull strings galore to get me chrome trim or else the deal was off.
Cup replacement and questions

Injector cups=injector sleeves.

If they are the front 4 cylinders you can do them in cab with the ford installer/remover.

If they are the back 4 cylinders youll need the whittaker cup tool. And its not cheap. I know i have one.
It's the number 5 cylinder so if my math is correct it is passenger side 3rd one back, so it looks like I'm going to need that Whittaker cup tool. Anyone around Mesa, or Phoenix AZ have one we can use. Otherwise I'm going to have to buy it and sell it afterward. THanks for all the feedback guys. Also does ford sell just the one cup or do you have to buy a set of 8. On anothe r note, I'm frustrated becasue I just had these heads redone 1000 miles ago, (valve guides, hardened seats, magnafluxed and straightened) and they never mentioned anything wrong with the cups or their need for replacement. THis was a highly respected place in Phoenix that bulletproof sends their heads too. Is it normal for them not to check the cups. I paid over 1250 for their work on these.
on a 7.3 ive seen the cup have a burr/nick on it, guy went through 3 or 4 oring jobs before realizing it.
Thanks guys this is great. Keep the info coming. This truck is being fixed to go into the oil fields of ND. So it has to be rock solid and work daily for its food.. Thansk again for all the help. I'm going to forward this to my guy doing the work..
Have you called the shop that did the heads and asked them about it?
Thanks guys this is great. Keep the info coming. This truck is being fixed to go into the oil fields of ND. So it has to be rock solid and work daily for its food.. Thansk again for all the help. I'm going to forward this to my guy doing the work..

Good luck in the oil patch ! If something happens to my gig in KS, thats my next plan. I would love to go down there and weld.
Not to hijack, but I had a full offer to go work in the ND fields, but turned it down when they could only offer me cents more an hour than my current job..
Depending on the price of the tool you may be better off paying someone to replace it for you. Just my .02.
the cups come in packs of 4, try 3C3Z-9F538-AA

also if I were you I'd replace the injector hold down also for good measure and make sure it's torqued to spec
Just wanted to follow up this post. I had my mechanic take out all the injectors and check them for problems. Turns out another one was also ready to blow (#8). He hired another tech to look at my engine with a fresh set of eyes and the new mechanic told him the torque setting on all the ones he took out were off. Tightest was only at 14 lbs. So all injectors were taken out, cleaned, injectors cups cleaned and bore scoped to verify, new glow plug harness installed and all new orings and hold downs replaced. All oil cleared out of hold down locations and everything put back in and torqued to 26 lbs. SO far!!!!! 1800 miles later everything is good. Just shows you how valuable a good mechanic is and that bad torque setting on these 6.0 can be disastrous.
Thanks for the follow up. It's great when we all get to find out if we got it right. Good luck in the oil patch!!
Same problem with O ring blowing 3 times

My 2005 F250 with a 6.0 has had Injector O rings blown out three times. I just had the head gaskets, ARP studs put in, had Ford dealership inspect the heads and put new injector cups in less than 500 miles ago.The first time it blew was within 15 miles after getting it back from the mechanic. The second time I ran it less than 100 miles and had the same injector # 7 fail. I was told that the injector hold down bolts could stretch, so we replaced them. I drove it less than 400 miles the third and last time the injector o rings went out and am now getting diesel back in the coolant. The last time the injector failed it hydrolocked. Just trying to decide if I should replace the heads or if this is just an injector cup problem. Any advice would be appreciated.
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