#7 Fuel injector spraying out under cap onto valve cover

BillBallard

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I just replaced the valve cover gaskets on my 91 7.3idi. While cranking the engine and bleeding air out of the fuel line, I noticed atomized fuel spraying out under the injector cap on the #7 cylinder. The caps, O rings, and return lines were recently replaced. There were no cracks in the cap, and the return lines were fine. So I replaced the O rings, and it continued to spray. That’s where things stand at the moment.

I’m thinking a bad injector. I would greatly appreciate some guidance on this.

Thank you
 
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Nero

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Swap injectors with another cylinder, if the problem follows, bobs ya uncle.
 

franklin2

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The return system with the caps and o-rings are very low pressure. I would not think a leak there would spray. But the fuel coming out of the tip of the injector is another story, it's at 1800 psi. I would suspect the hard line connection on top of the injector. They are easy to cross thread.
 

Clb

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+1 on swapping out the #7 somewhere else, but these returns will leak if you look at them wrong.
+1 on the low pressure of the returns...
 
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